Merge tag 'loongarch-6.2' of...

Merge tag 'loongarch-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch updates from Huacai Chen:

 - Switch to relative exception tables

 - Add unaligned access support

 - Add alternative runtime patching mechanism

 - Add FDT booting support from efi system table

 - Add suspend/hibernation (ACPI S3/S4) support

 - Add basic STACKPROTECTOR support

 - Add ftrace (function tracer) support

 - Update the default config file

* tag 'loongarch-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (24 commits)
  LoongArch: Update Loongson-3 default config file
  LoongArch: modules/ftrace: Initialize PLT at load time
  LoongArch/ftrace: Add HAVE_FUNCTION_GRAPH_RET_ADDR_PTR support
  LoongArch/ftrace: Add HAVE_DYNAMIC_FTRACE_WITH_ARGS support
  LoongArch/ftrace: Add HAVE_DYNAMIC_FTRACE_WITH_REGS support
  LoongArch/ftrace: Add dynamic function graph tracer support
  LoongArch/ftrace: Add dynamic function tracer support
  LoongArch/ftrace: Add recordmcount support
  LoongArch/ftrace: Add basic support
  LoongArch: module: Use got/plt section indices for relocations
  LoongArch: Add basic STACKPROTECTOR support
  LoongArch: Add hibernation (ACPI S4) support
  LoongArch: Add suspend (ACPI S3) support
  LoongArch: Add processing ISA Node in DeviceTree
  LoongArch: Add FDT booting support from efi system table
  LoongArch: Use alternative to optimize libraries
  LoongArch: Add alternative runtime patching mechanism
  LoongArch: Add unaligned access support
  LoongArch: BPF: Add BPF exception tables
  LoongArch: Remove the .fixup section usage
  ...

Documentation/admin-guide/sysctl/kernel.rst

@@ -436,8 +436,8 @@ ignore-unaligned-usertrap
 
 On architectures where unaligned accesses cause traps, and where this
 feature is supported (``CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN``;
-currently, ``arc`` and ``ia64``), controls whether all unaligned traps
-are logged.
+currently, ``arc``, ``ia64`` and ``loongarch``), controls whether all
+unaligned traps are logged.
 
 = =============================================================
 0 Log all unaligned accesses.
@@ -1492,8 +1492,8 @@ unaligned-trap
 
 On architectures where unaligned accesses cause traps, and where this
 feature is supported (``CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW``; currently,
-``arc`` and ``parisc``), controls whether unaligned traps are caught
-and emulated (instead of failing).
+``arc``, ``parisc`` and ``loongarch``), controls whether unaligned traps
+are caught and emulated (instead of failing).
 
 = ========================================================
 0 Do not emulate unaligned accesses.

arch/loongarch/Kconfig

@@ -58,6 +58,7 @@ config LOONGARCH
 	select ARCH_WANTS_NO_INSTR
 	select BUILDTIME_TABLE_SORT
 	select COMMON_CLK
+	select CPU_PM
 	select EFI
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_CMOS_UPDATE
@@ -86,11 +87,18 @@ config LOONGARCH
 	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
 	select HAVE_ASM_MODVERSIONS
 	select HAVE_CONTEXT_TRACKING_USER
+	select HAVE_C_RECORDMCOUNT
 	select HAVE_DEBUG_STACKOVERFLOW
 	select HAVE_DMA_CONTIGUOUS
+	select HAVE_DYNAMIC_FTRACE
+	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
+	select HAVE_DYNAMIC_FTRACE_WITH_REGS
 	select HAVE_EBPF_JIT
 	select HAVE_EXIT_THREAD
 	select HAVE_FAST_GUP
+	select HAVE_FTRACE_MCOUNT_RECORD
+	select HAVE_FUNCTION_GRAPH_TRACER
+	select HAVE_FUNCTION_TRACER
 	select HAVE_GENERIC_VDSO
 	select HAVE_IOREMAP_PROT
 	select HAVE_IRQ_EXIT_ON_IRQ_STACK
@@ -104,6 +112,7 @@ config LOONGARCH
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_RSEQ
 	select HAVE_SETUP_PER_CPU_AREA if NUMA
+	select HAVE_STACKPROTECTOR
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_TIF_NOHZ
 	select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP
@@ -113,6 +122,8 @@ config LOONGARCH
 	select MODULES_USE_ELF_RELA if MODULES
 	select NEED_PER_CPU_EMBED_FIRST_CHUNK
 	select NEED_PER_CPU_PAGE_FIRST_CHUNK
+	select OF
+	select OF_EARLY_FLATTREE
 	select PCI
 	select PCI_DOMAINS_GENERIC
 	select PCI_ECAM if ACPI
@@ -123,6 +134,8 @@ config LOONGARCH
 	select RTC_LIB
 	select SMP
 	select SPARSE_IRQ
+	select SYSCTL_ARCH_UNALIGN_ALLOW
+	select SYSCTL_ARCH_UNALIGN_NO_WARN
 	select SYSCTL_EXCEPTION_TRACE
 	select SWIOTLB
 	select TRACE_IRQFLAGS_SUPPORT
@@ -516,6 +529,13 @@ config ARCH_MMAP_RND_BITS_MAX
 
 menu "Power management options"
 
+config ARCH_SUSPEND_POSSIBLE
+	def_bool y
+
+config ARCH_HIBERNATION_POSSIBLE
+	def_bool y
+
+source "kernel/power/Kconfig"
 source "drivers/acpi/Kconfig"
 
 endmenu

arch/loongarch/Makefile

@@ -25,6 +25,11 @@ endif
 32bit-emul		= elf32loongarch
 64bit-emul		= elf64loongarch
 
+ifdef CONFIG_DYNAMIC_FTRACE
+KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
+CC_FLAGS_FTRACE := -fpatchable-function-entry=2
+endif
+
 ifdef CONFIG_64BIT
 tool-archpref		= $(64bit-tool-archpref)
 UTS_MACHINE		:= loongarch64
@@ -104,6 +109,9 @@ endif
 libs-y += arch/loongarch/lib/
 libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
 
+# suspend and hibernation support
+drivers-$(CONFIG_PM)	+= arch/loongarch/power/
+
 ifeq ($(KBUILD_EXTMOD),)
 prepare: vdso_prepare
 vdso_prepare: prepare0

arch/loongarch/configs/loongson3_defconfig

@@ -34,12 +34,13 @@ CONFIG_SYSFS_DEPRECATED=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
-CONFIG_USERFAULTFD=y
+CONFIG_KALLSYMS_ALL=y
 CONFIG_PERF_EVENTS=y
-# CONFIG_COMPAT_BRK is not set
 CONFIG_LOONGARCH=y
 CONFIG_64BIT=y
 CONFIG_MACH_LOONGSON64=y
+CONFIG_PAGE_SIZE_16KB=y
+CONFIG_HZ_250=y
 CONFIG_DMI=y
 CONFIG_EFI=y
 CONFIG_SMP=y
@@ -47,14 +48,14 @@ CONFIG_HOTPLUG_CPU=y
 CONFIG_NR_CPUS=64
 CONFIG_NUMA=y
 CONFIG_KEXEC=y
-CONFIG_PAGE_SIZE_16KB=y
-CONFIG_HZ_250=y
+CONFIG_SUSPEND=y
+CONFIG_HIBERNATION=y
 CONFIG_ACPI=y
 CONFIG_ACPI_SPCR_TABLE=y
-CONFIG_ACPI_HOTPLUG_CPU=y
 CONFIG_ACPI_TAD=y
 CONFIG_ACPI_DOCK=y
 CONFIG_ACPI_IPMI=m
+CONFIG_ACPI_HOTPLUG_CPU=y
 CONFIG_ACPI_PCI_SLOT=y
 CONFIG_ACPI_HOTPLUG_MEMORY=y
 CONFIG_EFI_ZBOOT=y
@@ -73,17 +74,19 @@ CONFIG_UNIXWARE_DISKLABEL=y
 CONFIG_IOSCHED_BFQ=y
 CONFIG_BFQ_GROUP_IOSCHED=y
 CONFIG_BINFMT_MISC=m
-CONFIG_MEMORY_HOTPLUG=y
-CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE=y
-CONFIG_MEMORY_HOTREMOVE=y
-CONFIG_KSM=y
-CONFIG_TRANSPARENT_HUGEPAGE=y
+CONFIG_ZPOOL=y
 CONFIG_ZSWAP=y
 CONFIG_ZSWAP_COMPRESSOR_DEFAULT_ZSTD=y
-CONFIG_ZPOOL=y
 CONFIG_ZBUD=y
 CONFIG_Z3FOLD=y
 CONFIG_ZSMALLOC=m
+# CONFIG_COMPAT_BRK is not set
+CONFIG_MEMORY_HOTPLUG=y
+CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE=y
+CONFIG_MEMORY_HOTREMOVE=y
+CONFIG_KSM=y
+CONFIG_TRANSPARENT_HUGEPAGE=y
+CONFIG_USERFAULTFD=y
 CONFIG_NET=y
 CONFIG_PACKET=y
 CONFIG_UNIX=y
@@ -118,7 +121,6 @@ CONFIG_NETFILTER=y
 CONFIG_BRIDGE_NETFILTER=m
 CONFIG_NETFILTER_NETLINK_LOG=m
 CONFIG_NF_CONNTRACK=m
-CONFIG_NF_LOG_NETDEV=m
 CONFIG_NF_CONNTRACK_AMANDA=m
 CONFIG_NF_CONNTRACK_FTP=m
 CONFIG_NF_CONNTRACK_NETBIOS_NS=m
@@ -416,6 +418,7 @@ CONFIG_SCSI_VIRTIO=m
 CONFIG_ATA=y
 CONFIG_SATA_AHCI=y
 CONFIG_SATA_AHCI_PLATFORM=y
+CONFIG_AHCI_DWC=y
 CONFIG_PATA_ATIIXP=y
 CONFIG_PATA_PCMCIA=m
 CONFIG_MD=y
@@ -469,13 +472,11 @@ CONFIG_VIRTIO_NET=m
 # CONFIG_NET_VENDOR_ARC is not set
 # CONFIG_NET_VENDOR_ATHEROS is not set
 CONFIG_BNX2=y
-# CONFIG_NET_VENDOR_BROCADE is not set
 # CONFIG_NET_VENDOR_CAVIUM is not set
 CONFIG_CHELSIO_T1=m
 CONFIG_CHELSIO_T1_1G=y
 CONFIG_CHELSIO_T3=m
 CONFIG_CHELSIO_T4=m
-# CONFIG_NET_VENDOR_CIRRUS is not set
 # CONFIG_NET_VENDOR_CISCO is not set
 # CONFIG_NET_VENDOR_DEC is not set
 # CONFIG_NET_VENDOR_DLINK is not set
@@ -496,6 +497,7 @@ CONFIG_IXGBE=y
 # CONFIG_NET_VENDOR_NVIDIA is not set
 # CONFIG_NET_VENDOR_OKI is not set
 # CONFIG_NET_VENDOR_QLOGIC is not set
+# CONFIG_NET_VENDOR_BROCADE is not set
 # CONFIG_NET_VENDOR_QUALCOMM is not set
 # CONFIG_NET_VENDOR_RDC is not set
 CONFIG_8139CP=m
@@ -505,9 +507,9 @@ CONFIG_R8169=y
 # CONFIG_NET_VENDOR_ROCKER is not set
 # CONFIG_NET_VENDOR_SAMSUNG is not set
 # CONFIG_NET_VENDOR_SEEQ is not set
-# CONFIG_NET_VENDOR_SOLARFLARE is not set
 # CONFIG_NET_VENDOR_SILAN is not set
 # CONFIG_NET_VENDOR_SIS is not set
+# CONFIG_NET_VENDOR_SOLARFLARE is not set
 # CONFIG_NET_VENDOR_SMSC is not set
 CONFIG_STMMAC_ETH=y
 # CONFIG_NET_VENDOR_SUN is not set
@@ -588,6 +590,7 @@ CONFIG_SERIAL_8250_EXTENDED=y
 CONFIG_SERIAL_8250_MANY_PORTS=y
 CONFIG_SERIAL_8250_SHARE_IRQ=y
 CONFIG_SERIAL_8250_RSA=y
+CONFIG_SERIAL_OF_PLATFORM=y
 CONFIG_SERIAL_NONSTANDARD=y
 CONFIG_PRINTER=m
 CONFIG_VIRTIO_CONSOLE=y
@@ -602,6 +605,11 @@ CONFIG_I2C_GPIO=y
 CONFIG_SPI=y
 CONFIG_GPIO_SYSFS=y
 CONFIG_GPIO_LOONGSON=y
+CONFIG_POWER_RESET=y
+CONFIG_POWER_RESET_RESTART=y
+CONFIG_POWER_RESET_SYSCON=y
+CONFIG_POWER_RESET_SYSCON_POWEROFF=y
+CONFIG_SYSCON_REBOOT_MODE=y
 CONFIG_SENSORS_LM75=m
 CONFIG_SENSORS_LM93=m
 CONFIG_SENSORS_W83795=m
@@ -609,16 +617,16 @@ CONFIG_SENSORS_W83627HF=m
 CONFIG_RC_CORE=m
 CONFIG_LIRC=y
 CONFIG_RC_DECODERS=y
+CONFIG_IR_IMON_DECODER=m
+CONFIG_IR_JVC_DECODER=m
+CONFIG_IR_MCE_KBD_DECODER=m
 CONFIG_IR_NEC_DECODER=m
 CONFIG_IR_RC5_DECODER=m
 CONFIG_IR_RC6_DECODER=m
-CONFIG_IR_JVC_DECODER=m
-CONFIG_IR_SONY_DECODER=m
 CONFIG_IR_SANYO_DECODER=m
 CONFIG_IR_SHARP_DECODER=m
-CONFIG_IR_MCE_KBD_DECODER=m
+CONFIG_IR_SONY_DECODER=m
 CONFIG_IR_XMP_DECODER=m
-CONFIG_IR_IMON_DECODER=m
 CONFIG_MEDIA_SUPPORT=m
 CONFIG_MEDIA_USB_SUPPORT=y
 CONFIG_USB_VIDEO_CLASS=m
@@ -638,6 +646,7 @@ CONFIG_DRM_VIRTIO_GPU=m
 CONFIG_FB=y
 CONFIG_FB_EFI=y
 CONFIG_FB_RADEON=y
+CONFIG_LCD_CLASS_DEVICE=y
 CONFIG_LCD_PLATFORM=m
 # CONFIG_VGA_CONSOLE is not set
 CONFIG_FRAMEBUFFER_CONSOLE=y
@@ -647,7 +656,6 @@ CONFIG_SOUND=y
 CONFIG_SND=y
 CONFIG_SND_SEQUENCER=m
 CONFIG_SND_SEQ_DUMMY=m
-# CONFIG_SND_ISA is not set
 CONFIG_SND_BT87X=m
 CONFIG_SND_BT87X_OVERCLOCK=y
 CONFIG_SND_HDA_INTEL=y
@@ -818,10 +826,6 @@ CONFIG_CRYPTO_USER=m
 # CONFIG_CRYPTO_MANAGER_DISABLE_TESTS is not set
 CONFIG_CRYPTO_PCRYPT=m
 CONFIG_CRYPTO_CRYPTD=m
-CONFIG_CRYPTO_CHACHA20POLY1305=m
-CONFIG_CRYPTO_HMAC=y
-CONFIG_CRYPTO_VMAC=m
-CONFIG_CRYPTO_WP512=m
 CONFIG_CRYPTO_ANUBIS=m
 CONFIG_CRYPTO_BLOWFISH=m
 CONFIG_CRYPTO_CAST5=m
@@ -831,6 +835,9 @@ CONFIG_CRYPTO_SEED=m
 CONFIG_CRYPTO_SERPENT=m
 CONFIG_CRYPTO_TEA=m
 CONFIG_CRYPTO_TWOFISH=m
+CONFIG_CRYPTO_CHACHA20POLY1305=m
+CONFIG_CRYPTO_VMAC=m
+CONFIG_CRYPTO_WP512=m
 CONFIG_CRYPTO_DEFLATE=m
 CONFIG_CRYPTO_LZO=m
 CONFIG_CRYPTO_842=m
@@ -844,6 +851,7 @@ CONFIG_CRYPTO_DEV_VIRTIO=m
 CONFIG_PRINTK_TIME=y
 CONFIG_STRIP_ASM_SYMS=y
 CONFIG_MAGIC_SYSRQ=y
+CONFIG_DEBUG_FS=y
 # CONFIG_SCHED_DEBUG is not set
 CONFIG_SCHEDSTATS=y
 # CONFIG_DEBUG_PREEMPT is not set

arch/loongarch/include/asm/acpi.h

@@ -35,4 +35,14 @@ extern struct list_head acpi_wakeup_device_list;
 
 #define ACPI_TABLE_UPGRADE_MAX_PHYS ARCH_LOW_ADDRESS_LIMIT
 
+extern int loongarch_acpi_suspend(void);
+extern int (*acpi_suspend_lowlevel)(void);
+extern void loongarch_suspend_enter(void);
+
+static inline unsigned long acpi_get_wakeup_address(void)
+{
+	extern void loongarch_wakeup_start(void);
+	return (unsigned long)loongarch_wakeup_start;
+}
+
 #endif /* _ASM_LOONGARCH_ACPI_H */

arch/loongarch/include/asm/alternative-asm.h

+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_ALTERNATIVE_ASM_H
+#define _ASM_ALTERNATIVE_ASM_H
+
+#ifdef __ASSEMBLY__
+
+#include <asm/asm.h>
+
+/*
+ * Issue one struct alt_instr descriptor entry (need to put it into
+ * the section .altinstructions, see below). This entry contains
+ * enough information for the alternatives patching code to patch an
+ * instruction. See apply_alternatives().
+ */
+.macro altinstruction_entry orig alt feature orig_len alt_len
+	.long \orig - .
+	.long \alt - .
+	.short \feature
+	.byte \orig_len
+	.byte \alt_len
+.endm
+
+/*
+ * Define an alternative between two instructions. If @feature is
+ * present, early code in apply_alternatives() replaces @oldinstr with
+ * @newinstr. ".fill" directive takes care of proper instruction padding
+ * in case @newinstr is longer than @oldinstr.
+ */
+.macro ALTERNATIVE oldinstr, newinstr, feature
+140 :
+	\oldinstr
+141 :
+	.fill - (((144f-143f)-(141b-140b)) > 0) * ((144f-143f)-(141b-140b)) / 4, 4, 0x03400000
+142 :
+
+	.pushsection .altinstructions, "a"
+	altinstruction_entry 140b, 143f, \feature, 142b-140b, 144f-143f
+	.popsection
+
+	.subsection 1
+143 :
+	\newinstr
+144 :
+	.previous
+.endm
+
+#define old_len			(141b-140b)
+#define new_len1		(144f-143f)
+#define new_len2		(145f-144f)
+
+#define alt_max_short(a, b)	((a) ^ (((a) ^ (b)) & -(-((a) < (b)))))
+
+/*
+ * Same as ALTERNATIVE macro above but for two alternatives. If CPU
+ * has @feature1, it replaces @oldinstr with @newinstr1. If CPU has
+ * @feature2, it replaces @oldinstr with @feature2.
+ */
+.macro ALTERNATIVE_2 oldinstr, newinstr1, feature1, newinstr2, feature2
+140 :
+	\oldinstr
+141 :
+	.fill - ((alt_max_short(new_len1, new_len2) - (old_len)) > 0) * \
+		(alt_max_short(new_len1, new_len2) - (old_len)) / 4, 4, 0x03400000
+142 :
+
+	.pushsection .altinstructions, "a"
+	altinstruction_entry 140b, 143f, \feature1, 142b-140b, 144f-143f, 142b-141b
+	altinstruction_entry 140b, 144f, \feature2, 142b-140b, 145f-144f, 142b-141b
+	.popsection
+
+	.subsection 1
+143 :
+	\newinstr1
+144 :
+	\newinstr2
+145 :
+	.previous
+.endm
+
+#endif  /*  __ASSEMBLY__  */
+
+#endif /* _ASM_ALTERNATIVE_ASM_H */

arch/loongarch/include/asm/alternative.h

+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_ALTERNATIVE_H
+#define _ASM_ALTERNATIVE_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/stringify.h>
+#include <asm/asm.h>
+
+struct alt_instr {
+	s32 instr_offset;	/* offset to original instruction */
+	s32 replace_offset;	/* offset to replacement instruction */
+	u16 feature;		/* feature bit set for replacement */
+	u8  instrlen;		/* length of original instruction */
+	u8  replacementlen;	/* length of new instruction */
+} __packed;
+
+/*
+ * Debug flag that can be tested to see whether alternative
+ * instructions were patched in already:
+ */
+extern int alternatives_patched;
+extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
+
+extern void alternative_instructions(void);
+extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end);
+
+#define b_replacement(num)	"664"#num
+#define e_replacement(num)	"665"#num
+
+#define alt_end_marker		"663"
+#define alt_slen		"662b-661b"
+#define alt_total_slen		alt_end_marker"b-661b"
+#define alt_rlen(num)		e_replacement(num)"f-"b_replacement(num)"f"
+
+#define __OLDINSTR(oldinstr, num)					\
+	"661:\n\t" oldinstr "\n662:\n"					\
+	".fill -(((" alt_rlen(num) ")-(" alt_slen ")) > 0) * "		\
+		"((" alt_rlen(num) ")-(" alt_slen ")) / 4, 4, 0x03400000\n"
+
+#define OLDINSTR(oldinstr, num)						\
+	__OLDINSTR(oldinstr, num)					\
+	alt_end_marker ":\n"
+
+#define alt_max_short(a, b)	"((" a ") ^ (((" a ") ^ (" b ")) & -(-((" a ") < (" b ")))))"
+
+/*
+ * Pad the second replacement alternative with additional NOPs if it is
+ * additionally longer than the first replacement alternative.
+ */
+#define OLDINSTR_2(oldinstr, num1, num2) \
+	"661:\n\t" oldinstr "\n662:\n"								\
+	".fill -((" alt_max_short(alt_rlen(num1), alt_rlen(num2)) " - (" alt_slen ")) > 0) * "	\
+		"(" alt_max_short(alt_rlen(num1), alt_rlen(num2)) " - (" alt_slen ")) / 4, "	\
+		"4, 0x03400000\n"	\
+	alt_end_marker ":\n"
+
+#define ALTINSTR_ENTRY(feature, num)					      \
+	" .long 661b - .\n"				/* label           */ \
+	" .long " b_replacement(num)"f - .\n"		/* new instruction */ \
+	" .short " __stringify(feature) "\n"		/* feature bit     */ \
+	" .byte " alt_total_slen "\n"			/* source len      */ \
+	" .byte " alt_rlen(num) "\n"			/* replacement len */
+
+#define ALTINSTR_REPLACEMENT(newinstr, feature, num)	/* replacement */     \
+	b_replacement(num)":\n\t" newinstr "\n" e_replacement(num) ":\n\t"
+
+/* alternative assembly primitive: */
+#define ALTERNATIVE(oldinstr, newinstr, feature)			\
+	OLDINSTR(oldinstr, 1)						\
+	".pushsection .altinstructions,\"a\"\n"				\
+	ALTINSTR_ENTRY(feature, 1)					\
+	".popsection\n"							\
+	".subsection 1\n" \
+	ALTINSTR_REPLACEMENT(newinstr, feature, 1)			\
+	".previous\n"
+
+#define ALTERNATIVE_2(oldinstr, newinstr1, feature1, newinstr2, feature2)\
+	OLDINSTR_2(oldinstr, 1, 2)					\
+	".pushsection .altinstructions,\"a\"\n"				\
+	ALTINSTR_ENTRY(feature1, 1)					\
+	ALTINSTR_ENTRY(feature2, 2)					\
+	".popsection\n"							\
+	".subsection 1\n" \
+	ALTINSTR_REPLACEMENT(newinstr1, feature1, 1)			\
+	ALTINSTR_REPLACEMENT(newinstr2, feature2, 2)			\
+	".previous\n"
+
+/*
+ * Alternative instructions for different CPU types or capabilities.
+ *
+ * This allows to use optimized instructions even on generic binary
+ * kernels.
+ *
+ * length of oldinstr must be longer or equal the length of newinstr
+ * It can be padded with nops as needed.
+ *
+ * For non barrier like inlines please define new variants
+ * without volatile and memory clobber.
+ */
+#define alternative(oldinstr, newinstr, feature)			\
+	(asm volatile (ALTERNATIVE(oldinstr, newinstr, feature) : : : "memory"))
+
+#define alternative_2(oldinstr, newinstr1, feature1, newinstr2, feature2) \
+	(asm volatile(ALTERNATIVE_2(oldinstr, newinstr1, feature1, newinstr2, feature2) ::: "memory"))
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_ALTERNATIVE_H */

arch/loongarch/include/asm/asm-extable.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __ASM_ASM_EXTABLE_H
+#define __ASM_ASM_EXTABLE_H
+
+#define EX_TYPE_NONE			0
+#define EX_TYPE_FIXUP			1
+#define EX_TYPE_UACCESS_ERR_ZERO	2
+#define EX_TYPE_BPF			3
+
+#ifdef __ASSEMBLY__
+
+#define __ASM_EXTABLE_RAW(insn, fixup, type, data)	\
+	.pushsection	__ex_table, "a";		\
+	.balign		4;				\
+	.long		((insn) - .);			\
+	.long		((fixup) - .);			\
+	.short		(type);				\
+	.short		(data);				\
+	.popsection;
+
+	.macro		_asm_extable, insn, fixup
+	__ASM_EXTABLE_RAW(\insn, \fixup, EX_TYPE_FIXUP, 0)
+	.endm
+
+#else /* __ASSEMBLY__ */
+
+#include <linux/bits.h>
+#include <linux/stringify.h>
+#include <asm/gpr-num.h>
+
+#define __ASM_EXTABLE_RAW(insn, fixup, type, data)	\
+	".pushsection	__ex_table, \"a\"\n"		\
+	".balign	4\n"				\
+	".long		((" insn ") - .)\n"		\
+	".long		((" fixup ") - .)\n"		\
+	".short		(" type ")\n"			\
+	".short		(" data ")\n"			\
+	".popsection\n"
+
+#define _ASM_EXTABLE(insn, fixup)	\
+	__ASM_EXTABLE_RAW(#insn, #fixup, __stringify(EX_TYPE_FIXUP), "0")
+
+#define EX_DATA_REG_ERR_SHIFT	0
+#define EX_DATA_REG_ERR		GENMASK(4, 0)
+#define EX_DATA_REG_ZERO_SHIFT	5
+#define EX_DATA_REG_ZERO	GENMASK(9, 5)
+
+#define EX_DATA_REG(reg, gpr)						\
+	"((.L__gpr_num_" #gpr ") << " __stringify(EX_DATA_REG_##reg##_SHIFT) ")"
+
+#define _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)		\
+	__DEFINE_ASM_GPR_NUMS						\
+	__ASM_EXTABLE_RAW(#insn, #fixup, 				\
+			  __stringify(EX_TYPE_UACCESS_ERR_ZERO),	\
+			  "("						\
+			    EX_DATA_REG(ERR, err) " | "			\
+			    EX_DATA_REG(ZERO, zero)			\
+			  ")")
+
+#define _ASM_EXTABLE_UACCESS_ERR(insn, fixup, err)			\
+	_ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_ASM_EXTABLE_H */

arch/loongarch/include/asm/bootinfo.h

@@ -32,6 +32,7 @@ struct loongson_system_configuration {
 	int cores_per_node;
 	int cores_per_package;
 	unsigned long cores_io_master;
+	unsigned long suspend_addr;
 	const char *cpuname;
 };
 

arch/loongarch/include/asm/bugs.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This is included by init/main.c to check for architecture-dependent bugs.
+ *
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#ifndef _ASM_BUGS_H
+#define _ASM_BUGS_H
+
+#include <asm/cpu.h>
+#include <asm/cpu-info.h>
+
+extern void check_bugs(void);
+
+#endif /* _ASM_BUGS_H */

arch/loongarch/include/asm/efi.h

@@ -9,6 +9,7 @@
 
 void __init efi_init(void);
 void __init efi_runtime_init(void);
+void __init *efi_fdt_pointer(void);
 void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
 
 #define ARCH_EFI_IRQ_FLAGS_MASK  0x00000004  /* Bit 2: CSR.CRMD.IE */

arch/loongarch/include/asm/extable.h

+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_LOONGARCH_EXTABLE_H
+#define _ASM_LOONGARCH_EXTABLE_H
+
+/*
+ * The exception table consists of pairs of relative offsets: the first
+ * is the relative offset to an instruction that is allowed to fault,
+ * and the second is the relative offset at which the program should
+ * continue. No registers are modified, so it is entirely up to the
+ * continuation code to figure out what to do.
+ *
+ * All the routines below use bits of fixup code that are out of line
+ * with the main instruction path.  This means when everything is well,
+ * we don't even have to jump over them.  Further, they do not intrude
+ * on our cache or tlb entries.
+ */
+
+struct exception_table_entry {
+	int insn, fixup;
+	short type, data;
+};
+
+#define ARCH_HAS_RELATIVE_EXTABLE
+
+#define swap_ex_entry_fixup(a, b, tmp, delta)		\
+do {							\
+	(a)->fixup = (b)->fixup + (delta);		\
+	(b)->fixup = (tmp).fixup - (delta);		\
+	(a)->type = (b)->type;				\
+	(b)->type = (tmp).type;				\
+	(a)->data = (b)->data;				\
+	(b)->data = (tmp).data;				\
+} while (0)
+
+#ifdef CONFIG_BPF_JIT
+bool ex_handler_bpf(const struct exception_table_entry *ex, struct pt_regs *regs);
+#else
+static inline
+bool ex_handler_bpf(const struct exception_table_entry *ex, struct pt_regs *regs)
+{
+	return false;
+}
+#endif /* !CONFIG_BPF_JIT */
+
+bool fixup_exception(struct pt_regs *regs);
+
+#endif

arch/loongarch/include/asm/ftrace.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+
+#ifndef _ASM_LOONGARCH_FTRACE_H
+#define _ASM_LOONGARCH_FTRACE_H
+
+#define FTRACE_PLT_IDX		0
+#define FTRACE_REGS_PLT_IDX	1
+#define NR_FTRACE_PLTS		2
+
+#define GRAPH_FAKE_OFFSET (sizeof(struct pt_regs) - offsetof(struct pt_regs, regs[1]))
+
+#ifdef CONFIG_FUNCTION_TRACER
+
+#define MCOUNT_INSN_SIZE 4		/* sizeof mcount call */
+
+#ifndef __ASSEMBLY__
+
+#ifndef CONFIG_DYNAMIC_FTRACE
+
+#define mcount _mcount
+extern void _mcount(void);
+extern void prepare_ftrace_return(unsigned long self_addr, unsigned long callsite_sp, unsigned long old);
+
+#else
+
+struct dyn_ftrace;
+struct dyn_arch_ftrace { };
+
+#define ARCH_SUPPORTS_FTRACE_OPS 1
+#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
+
+#define ftrace_init_nop ftrace_init_nop
+int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
+
+static inline unsigned long ftrace_call_adjust(unsigned long addr)
+{
+	return addr;
+}
+
+void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent);
+
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
+struct ftrace_ops;
+
+struct ftrace_regs {
+	struct pt_regs regs;
+};
+
+static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs)
+{
+	return &fregs->regs;
+}
+
+#define ftrace_graph_func ftrace_graph_func
+void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
+		       struct ftrace_ops *op, struct ftrace_regs *fregs);
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* CONFIG_FUNCTION_TRACER */
+
+#endif /* _ASM_LOONGARCH_FTRACE_H */

arch/loongarch/include/asm/futex.h

@@ -7,6 +7,7 @@
 
 #include <linux/futex.h>
 #include <linux/uaccess.h>
+#include <asm/asm-extable.h>
 #include <asm/barrier.h>
 #include <asm/errno.h>
 
@@ -18,18 +19,11 @@
 	"2:	sc.w	$t0, %2				\n"	\
 	"	beqz	$t0, 1b				\n"	\
 	"3:						\n"	\
-	"	.section .fixup,\"ax\"			\n"	\
-	"4:	li.w	%0, %6				\n"	\
-	"	b	3b				\n"	\
-	"	.previous				\n"	\
-	"	.section __ex_table,\"a\"		\n"	\
-	"	"__UA_ADDR "\t1b, 4b			\n"	\
-	"	"__UA_ADDR "\t2b, 4b			\n"	\
-	"	.previous				\n"	\
+	_ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0)			\
+	_ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0)			\
 	: "=r" (ret), "=&r" (oldval),				\
 	  "=ZC" (*uaddr)					\
-	: "0" (0), "ZC" (*uaddr), "Jr" (oparg),			\
-	  "i" (-EFAULT)						\
+	: "0" (0), "ZC" (*uaddr), "Jr" (oparg)			\
 	: "memory", "t0");					\
 }
 
@@ -86,17 +80,10 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, u32 newv
 	"	beqz	$t0, 1b					\n"
 	"3:							\n"
 	__WEAK_LLSC_MB
-	"	.section .fixup,\"ax\"				\n"
-	"4:	li.d	%0, %6					\n"
-	"	b	3b					\n"
-	"	.previous					\n"
-	"	.section __ex_table,\"a\"			\n"
-	"	"__UA_ADDR "\t1b, 4b				\n"
-	"	"__UA_ADDR "\t2b, 4b				\n"
-	"	.previous					\n"
+	_ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0)
+	_ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0)
 	: "+r" (ret), "=&r" (val), "=ZC" (*uaddr)
-	: "ZC" (*uaddr), "Jr" (oldval), "Jr" (newval),
-	  "i" (-EFAULT)
+	: "ZC" (*uaddr), "Jr" (oldval), "Jr" (newval)
 	: "memory", "t0");
 
 	*uval = val;

arch/loongarch/include/asm/gpr-num.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __ASM_GPR_NUM_H
+#define __ASM_GPR_NUM_H
+
+#ifdef __ASSEMBLY__
+
+	.equ	.L__gpr_num_zero, 0
+	.irp	num,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31
+	.equ	.L__gpr_num_$r\num, \num
+	.endr
+
+#else /* __ASSEMBLY__ */
+
+#define __DEFINE_ASM_GPR_NUMS					\
+"	.equ	.L__gpr_num_zero, 0\n"				\
+"	.irp	num,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31\n" \
+"	.equ	.L__gpr_num_$r\\num, \\num\n"			\
+"	.endr\n"						\
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_GPR_NUM_H */

arch/loongarch/include/asm/inst.h

@@ -8,14 +8,17 @@
 #include <linux/types.h>
 #include <asm/asm.h>
 
+#define INSN_NOP		0x03400000
 #define INSN_BREAK		0x002a0000
 
 #define ADDR_IMMMASK_LU52ID	0xFFF0000000000000
 #define ADDR_IMMMASK_LU32ID	0x000FFFFF00000000
+#define ADDR_IMMMASK_LU12IW	0x00000000FFFFF000
 #define ADDR_IMMMASK_ADDU16ID	0x00000000FFFF0000
 
 #define ADDR_IMMSHIFT_LU52ID	52
 #define ADDR_IMMSHIFT_LU32ID	32
+#define ADDR_IMMSHIFT_LU12IW	12
 #define ADDR_IMMSHIFT_ADDU16ID	16
 
 #define ADDR_IMM(addr, INSN)	((addr & ADDR_IMMMASK_##INSN) >> ADDR_IMMSHIFT_##INSN)
@@ -28,6 +31,7 @@ enum reg0i26_op {
 enum reg1i20_op {
 	lu12iw_op	= 0x0a,
 	lu32id_op	= 0x0b,
+	pcaddi_op	= 0x0c,
 	pcaddu12i_op	= 0x0e,
 	pcaddu18i_op	= 0x0f,
 };
@@ -35,6 +39,8 @@ enum reg1i20_op {
 enum reg1i21_op {
 	beqz_op		= 0x10,
 	bnez_op		= 0x11,
+	bceqz_op	= 0x12, /* bits[9:8] = 0x00 */
+	bcnez_op	= 0x12, /* bits[9:8] = 0x01 */
 };
 
 enum reg2_op {
@@ -76,6 +82,10 @@ enum reg2i12_op {
 	ldbu_op		= 0xa8,
 	ldhu_op		= 0xa9,
 	ldwu_op		= 0xaa,
+	flds_op		= 0xac,
+	fsts_op		= 0xad,
+	fldd_op		= 0xae,
+	fstd_op		= 0xaf,
 };
 
 enum reg2i14_op {
@@ -146,6 +156,10 @@ enum reg3_op {
 	ldxbu_op	= 0x7040,
 	ldxhu_op	= 0x7048,
 	ldxwu_op	= 0x7050,
+	fldxs_op	= 0x7060,
+	fldxd_op	= 0x7068,
+	fstxs_op	= 0x7070,
+	fstxd_op	= 0x7078,
 	amswapw_op	= 0x70c0,
 	amswapd_op	= 0x70c1,
 	amaddw_op	= 0x70c2,
@@ -307,6 +321,12 @@ static inline bool is_imm_negative(unsigned long val, unsigned int bit)
 	return val & (1UL << (bit - 1));
 }
 
+static inline bool is_pc_ins(union loongarch_instruction *ip)
+{
+	return ip->reg1i20_format.opcode >= pcaddi_op &&
+			ip->reg1i20_format.opcode <= pcaddu18i_op;
+}
+
 static inline bool is_branch_ins(union loongarch_instruction *ip)
 {
 	return ip->reg1i21_format.opcode >= beqz_op &&
@@ -331,6 +351,18 @@ static inline bool is_stack_alloc_ins(union loongarch_instruction *ip)
 		is_imm12_negative(ip->reg2i12_format.immediate);
 }
 
+int larch_insn_read(void *addr, u32 *insnp);
+int larch_insn_write(void *addr, u32 insn);
+int larch_insn_patch_text(void *addr, u32 insn);
+
+u32 larch_insn_gen_nop(void);
+u32 larch_insn_gen_b(unsigned long pc, unsigned long dest);
+u32 larch_insn_gen_bl(unsigned long pc, unsigned long dest);
+
+u32 larch_insn_gen_or(enum loongarch_gpr rd, enum loongarch_gpr rj, enum loongarch_gpr rk);
+u32 larch_insn_gen_move(enum loongarch_gpr rd, enum loongarch_gpr rj);
+
+u32 larch_insn_gen_lu12iw(enum loongarch_gpr rd, int imm);
 u32 larch_insn_gen_lu32id(enum loongarch_gpr rd, int imm);
 u32 larch_insn_gen_lu52id(enum loongarch_gpr rd, enum loongarch_gpr rj, int imm);
 u32 larch_insn_gen_jirl(enum loongarch_gpr rd, enum loongarch_gpr rj, unsigned long pc, unsigned long dest);
@@ -345,6 +377,14 @@ static inline bool unsigned_imm_check(unsigned long val, unsigned int bit)
 	return val < (1UL << bit);
 }
 
+static inline unsigned long sign_extend(unsigned long val, unsigned int idx)
+{
+	if (!is_imm_negative(val, idx + 1))
+		return ((1UL << idx) - 1) & val;
+	else
+		return ~((1UL << idx) - 1) | val;
+}
+
 #define DEF_EMIT_REG0I26_FORMAT(NAME, OP)				\
 static inline void emit_##NAME(union loongarch_instruction *insn,	\
 			       int offset)				\
@@ -566,4 +606,10 @@ static inline void emit_##NAME(union loongarch_instruction *insn,	\
 
 DEF_EMIT_REG3SA2_FORMAT(alsld, alsld_op)
 
+struct pt_regs;
+
+void emulate_load_store_insn(struct pt_regs *regs, void __user *addr, unsigned int *pc);
+unsigned long unaligned_read(void __user *addr, void *value, unsigned long n, bool sign);
+unsigned long unaligned_write(void __user *addr, unsigned long value, unsigned long n);
+
 #endif /* _ASM_INST_H */

arch/loongarch/include/asm/loongson.h

@@ -136,4 +136,7 @@ typedef enum {
 #define ls7a_writel(val, addr)	*(volatile unsigned int   *)TO_UNCACHE(addr) = (val)
 #define ls7a_writeq(val, addr)	*(volatile unsigned long  *)TO_UNCACHE(addr) = (val)
 
+void enable_gpe_wakeup(void);
+void enable_pci_wakeup(void);
+
 #endif /* __ASM_LOONGSON_H */

arch/loongarch/include/asm/module.h

@@ -11,7 +11,7 @@
 #define RELA_STACK_DEPTH 16
 
 struct mod_section {
-	Elf_Shdr *shdr;
+	int shndx;
 	int num_entries;
 	int max_entries;
 };
@@ -20,6 +20,9 @@ struct mod_arch_specific {
 	struct mod_section got;
 	struct mod_section plt;
 	struct mod_section plt_idx;
+
+	/* For CONFIG_DYNAMIC_FTRACE */
+	struct plt_entry *ftrace_trampolines;
 };
 
 struct got_entry {
@@ -37,8 +40,8 @@ struct plt_idx_entry {
 	Elf_Addr symbol_addr;
 };
 
-Elf_Addr module_emit_got_entry(struct module *mod, Elf_Addr val);
-Elf_Addr module_emit_plt_entry(struct module *mod, Elf_Addr val);
+Elf_Addr module_emit_got_entry(struct module *mod, Elf_Shdr *sechdrs, Elf_Addr val);
+Elf_Addr module_emit_plt_entry(struct module *mod, Elf_Shdr *sechdrs, Elf_Addr val);
 
 static inline struct got_entry emit_got_entry(Elf_Addr val)
 {
@@ -49,7 +52,7 @@ static inline struct plt_entry emit_plt_entry(unsigned long val)
 {
 	u32 lu12iw, lu32id, lu52id, jirl;
 
-	lu12iw = (lu12iw_op << 25 | (((val >> 12) & 0xfffff) << 5) | LOONGARCH_GPR_T1);
+	lu12iw = larch_insn_gen_lu12iw(LOONGARCH_GPR_T1, ADDR_IMM(val, LU12IW));
 	lu32id = larch_insn_gen_lu32id(LOONGARCH_GPR_T1, ADDR_IMM(val, LU32ID));
 	lu52id = larch_insn_gen_lu52id(LOONGARCH_GPR_T1, LOONGARCH_GPR_T1, ADDR_IMM(val, LU52ID));
 	jirl = larch_insn_gen_jirl(0, LOONGARCH_GPR_T1, 0, (val & 0xfff));
@@ -62,10 +65,10 @@ static inline struct plt_idx_entry emit_plt_idx_entry(unsigned long val)
 	return (struct plt_idx_entry) { val };
 }
 
-static inline int get_plt_idx(unsigned long val, const struct mod_section *sec)
+static inline int get_plt_idx(unsigned long val, Elf_Shdr *sechdrs, const struct mod_section *sec)
 {
 	int i;
-	struct plt_idx_entry *plt_idx = (struct plt_idx_entry *)sec->shdr->sh_addr;
+	struct plt_idx_entry *plt_idx = (struct plt_idx_entry *)sechdrs[sec->shndx].sh_addr;
 
 	for (i = 0; i < sec->num_entries; i++) {
 		if (plt_idx[i].symbol_addr == val)
@@ -76,11 +79,12 @@ static inline int get_plt_idx(unsigned long val, const struct mod_section *sec)
 }
 
 static inline struct plt_entry *get_plt_entry(unsigned long val,
-				      const struct mod_section *sec_plt,
-				      const struct mod_section *sec_plt_idx)
+					      Elf_Shdr *sechdrs,
+					      const struct mod_section *sec_plt,
+					      const struct mod_section *sec_plt_idx)
 {
-	int plt_idx = get_plt_idx(val, sec_plt_idx);
-	struct plt_entry *plt = (struct plt_entry *)sec_plt->shdr->sh_addr;
+	int plt_idx = get_plt_idx(val, sechdrs, sec_plt_idx);
+	struct plt_entry *plt = (struct plt_entry *)sechdrs[sec_plt->shndx].sh_addr;
 
 	if (plt_idx < 0)
 		return NULL;
@@ -89,10 +93,11 @@ static inline struct plt_entry *get_plt_entry(unsigned long val,
 }
 
 static inline struct got_entry *get_got_entry(Elf_Addr val,
+					      Elf_Shdr *sechdrs,
 					      const struct mod_section *sec)
 {
-	struct got_entry *got = (struct got_entry *)sec->shdr->sh_addr;
 	int i;
+	struct got_entry *got = (struct got_entry *)sechdrs[sec->shndx].sh_addr;
 
 	for (i = 0; i < sec->num_entries; i++)
 		if (got[i].symbol_addr == val)

arch/loongarch/include/asm/module.lds.h

@@ -5,4 +5,5 @@ SECTIONS {
 	.got : { BYTE(0) }
 	.plt : { BYTE(0) }
 	.plt.idx : { BYTE(0) }
+	.ftrace_trampoline : { BYTE(0) }
 }

arch/loongarch/include/asm/setup.h

@@ -13,6 +13,7 @@
 
 extern unsigned long eentry;
 extern unsigned long tlbrentry;
+extern char init_command_line[COMMAND_LINE_SIZE];
 extern void tlb_init(int cpu);
 extern void cpu_cache_init(void);
 extern void cache_error_setup(void);

arch/loongarch/include/asm/stackprotector.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * GCC stack protector support.
+ *
+ * Stack protector works by putting predefined pattern at the start of
+ * the stack frame and verifying that it hasn't been overwritten when
+ * returning from the function. The pattern is called stack canary and
+ * on LoongArch gcc expects it to be defined by a global variable called
+ * "__stack_chk_guard".
+ */
+
+#ifndef _ASM_STACKPROTECTOR_H
+#define _ASM_STACKPROTECTOR_H
+
+#include <linux/random.h>
+#include <linux/version.h>
+
+extern unsigned long __stack_chk_guard;
+
+/*
+ * Initialize the stackprotector canary value.
+ *
+ * NOTE: this must only be called from functions that never return,
+ * and it must always be inlined.
+ */
+static __always_inline void boot_init_stack_canary(void)
+{
+	unsigned long canary;
+
+	/* Try to get a semi random initial value. */
+	get_random_bytes(&canary, sizeof(canary));
+	canary ^= LINUX_VERSION_CODE;
+
+	current->stack_canary = canary;
+	__stack_chk_guard = current->stack_canary;
+}
+
+#endif	/* _ASM_STACKPROTECTOR_H */

arch/loongarch/include/asm/string.h

@@ -5,8 +5,13 @@
 #ifndef _ASM_STRING_H
 #define _ASM_STRING_H
 
+#define __HAVE_ARCH_MEMSET
 extern void *memset(void *__s, int __c, size_t __count);
+
+#define __HAVE_ARCH_MEMCPY
 extern void *memcpy(void *__to, __const__ void *__from, size_t __n);
+
+#define __HAVE_ARCH_MEMMOVE
 extern void *memmove(void *__dest, __const__ void *__src, size_t __n);
 
 #endif /* _ASM_STRING_H */

arch/loongarch/include/asm/thread_info.h

@@ -38,7 +38,7 @@ struct thread_info {
 #define INIT_THREAD_INFO(tsk)			\
 {						\
 	.task		= &tsk,			\
-	.flags		= 0,			\
+	.flags		= _TIF_FIXADE,		\
 	.cpu		= 0,			\
 	.preempt_count	= INIT_PREEMPT_COUNT,	\
 }

arch/loongarch/include/asm/time.h

@@ -12,6 +12,7 @@
 extern u64 cpu_clock_freq;
 extern u64 const_clock_freq;
 
+extern void save_counter(void);
 extern void sync_counter(void);
 
 static inline unsigned int calc_const_freq(void)

arch/loongarch/include/asm/uaccess.h

@@ -15,7 +15,8 @@
 #include <linux/string.h>
 #include <linux/extable.h>
 #include <asm/pgtable.h>
-#include <asm-generic/extable.h>
+#include <asm/extable.h>
+#include <asm/asm-extable.h>
 #include <asm-generic/access_ok.h>
 
 extern u64 __ua_limit;
@@ -160,16 +161,9 @@ do {									\
 	__asm__ __volatile__(						\
 	"1:	" insn "	%1, %2				\n"	\
 	"2:							\n"	\
-	"	.section .fixup,\"ax\"				\n"	\
-	"3:	li.w	%0, %3					\n"	\
-	"	move	%1, $zero				\n"	\
-	"	b	2b					\n"	\
-	"	.previous					\n"	\
-	"	.section __ex_table,\"a\"			\n"	\
-	"	"__UA_ADDR "\t1b, 3b				\n"	\
-	"	.previous					\n"	\
+	_ASM_EXTABLE_UACCESS_ERR_ZERO(1b, 2b, %0, %1)			\
 	: "+r" (__gu_err), "=r" (__gu_tmp)				\
-	: "m" (__m(ptr)), "i" (-EFAULT));				\
+	: "m" (__m(ptr)));						\
 									\
 	(val) = (__typeof__(*(ptr))) __gu_tmp;				\
 }
@@ -192,15 +186,9 @@ do {									\
 	__asm__ __volatile__(						\
 	"1:	" insn "	%z2, %1		# __put_user_asm\n"	\
 	"2:							\n"	\
-	"	.section	.fixup,\"ax\"			\n"	\
-	"3:	li.w	%0, %3					\n"	\
-	"	b	2b					\n"	\
-	"	.previous					\n"	\
-	"	.section	__ex_table,\"a\"		\n"	\
-	"	" __UA_ADDR "	1b, 3b				\n"	\
-	"	.previous					\n"	\
+	_ASM_EXTABLE_UACCESS_ERR(1b, 2b, %0)				\
 	: "+r" (__pu_err), "=m" (__m(ptr))				\
-	: "Jr" (__pu_val), "i" (-EFAULT));				\
+	: "Jr" (__pu_val));						\
 }
 
 #define __get_kernel_nofault(dst, src, type, err_label)			\

arch/loongarch/include/asm/unwind.h

@@ -20,7 +20,8 @@ struct unwind_state {
 	char type; /* UNWINDER_XXX */
 	struct stack_info stack_info;
 	struct task_struct *task;
-	bool first, error;
+	bool first, error, is_ftrace;
+	int graph_idx;
 	unsigned long sp, pc, ra;
 };
 

arch/loongarch/kernel/Makefile

@@ -7,13 +7,27 @@ extra-y		:= vmlinux.lds
 
 obj-y		+= head.o cpu-probe.o cacheinfo.o env.o setup.o entry.o genex.o \
 		   traps.o irq.o idle.o process.o dma.o mem.o io.o reset.o switch.o \
-		   elf.o syscall.o signal.o time.o topology.o inst.o ptrace.o vdso.o
+		   elf.o syscall.o signal.o time.o topology.o inst.o ptrace.o vdso.o \
+		   alternative.o unaligned.o
 
 obj-$(CONFIG_ACPI)		+= acpi.o
 obj-$(CONFIG_EFI) 		+= efi.o
 
 obj-$(CONFIG_CPU_HAS_FPU)	+= fpu.o
 
+ifdef CONFIG_FUNCTION_TRACER
+  ifndef CONFIG_DYNAMIC_FTRACE
+    obj-y += mcount.o ftrace.o
+    CFLAGS_REMOVE_ftrace.o = $(CC_FLAGS_FTRACE)
+  else
+    obj-y += mcount_dyn.o ftrace_dyn.o
+    CFLAGS_REMOVE_ftrace_dyn.o = $(CC_FLAGS_FTRACE)
+  endif
+  CFLAGS_REMOVE_inst.o = $(CC_FLAGS_FTRACE)
+  CFLAGS_REMOVE_time.o = $(CC_FLAGS_FTRACE)
+  CFLAGS_REMOVE_perf_event.o = $(CC_FLAGS_FTRACE)
+endif
+
 obj-$(CONFIG_MODULES)		+= module.o module-sections.o
 obj-$(CONFIG_STACKTRACE)	+= stacktrace.o
 

arch/loongarch/kernel/acpi.c

@@ -12,6 +12,7 @@
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
 #include <linux/memblock.h>
+#include <linux/of_fdt.h>
 #include <linux/serial_core.h>
 #include <asm/io.h>
 #include <asm/numa.h>
@@ -139,20 +140,26 @@ static void __init acpi_process_madt(void)
 	loongson_sysconf.nr_cpus = num_processors;
 }
 
+#ifndef CONFIG_SUSPEND
+int (*acpi_suspend_lowlevel)(void);
+#else
+int (*acpi_suspend_lowlevel)(void) = loongarch_acpi_suspend;
+#endif
+
 void __init acpi_boot_table_init(void)
 {
 	/*
 	 * If acpi_disabled, bail out
 	 */
 	if (acpi_disabled)
-		return;
+		goto fdt_earlycon;
 
 	/*
 	 * Initialize the ACPI boot-time table parser.
 	 */
 	if (acpi_table_init()) {
 		disable_acpi();
-		return;
+		goto fdt_earlycon;
 	}
 
 	loongson_sysconf.boot_cpu_id = read_csr_cpuid();
@@ -164,6 +171,12 @@ void __init acpi_boot_table_init(void)
 
 	/* Do not enable ACPI SPCR console by default */
 	acpi_parse_spcr(earlycon_acpi_spcr_enable, false);
+
+	return;
+
+fdt_earlycon:
+	if (earlycon_acpi_spcr_enable)
+		early_init_dt_scan_chosen_stdout();
 }
 
 #ifdef CONFIG_ACPI_NUMA

arch/loongarch/kernel/alternative.c

+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <asm/alternative.h>
+#include <asm/cacheflush.h>
+#include <asm/inst.h>
+#include <asm/sections.h>
+
+int __read_mostly alternatives_patched;
+
+EXPORT_SYMBOL_GPL(alternatives_patched);
+
+#define MAX_PATCH_SIZE (((u8)(-1)) / LOONGARCH_INSN_SIZE)
+
+static int __initdata_or_module debug_alternative;
+
+static int __init debug_alt(char *str)
+{
+	debug_alternative = 1;
+	return 1;
+}
+__setup("debug-alternative", debug_alt);
+
+#define DPRINTK(fmt, args...)						\
+do {									\
+	if (debug_alternative)						\
+		printk(KERN_DEBUG "%s: " fmt "\n", __func__, ##args);	\
+} while (0)
+
+#define DUMP_WORDS(buf, count, fmt, args...)				\
+do {									\
+	if (unlikely(debug_alternative)) {				\
+		int _j;							\
+		union loongarch_instruction *_buf = buf;		\
+									\
+		if (!(count))						\
+			break;						\
+									\
+		printk(KERN_DEBUG fmt, ##args);				\
+		for (_j = 0; _j < count - 1; _j++)			\
+			printk(KERN_CONT "<%08x> ", _buf[_j].word);	\
+		printk(KERN_CONT "<%08x>\n", _buf[_j].word);		\
+	}								\
+} while (0)
+
+/* Use this to add nops to a buffer, then text_poke the whole buffer. */
+static void __init_or_module add_nops(union loongarch_instruction *insn, int count)
+{
+	while (count--) {
+		insn->word = INSN_NOP;
+		insn++;
+	}
+}
+
+/* Is the jump addr in local .altinstructions */
+static inline bool in_alt_jump(unsigned long jump, void *start, void *end)
+{
+	return jump >= (unsigned long)start && jump < (unsigned long)end;
+}
+
+static void __init_or_module recompute_jump(union loongarch_instruction *buf,
+		union loongarch_instruction *dest, union loongarch_instruction *src,
+		void *start, void *end)
+{
+	unsigned int si, si_l, si_h;
+	unsigned long cur_pc, jump_addr, pc;
+	long offset;
+
+	cur_pc = (unsigned long)src;
+	pc = (unsigned long)dest;
+
+	si_l = src->reg0i26_format.immediate_l;
+	si_h = src->reg0i26_format.immediate_h;
+	switch (src->reg0i26_format.opcode) {
+	case b_op:
+	case bl_op:
+		jump_addr = cur_pc + sign_extend((si_h << 16 | si_l) << 2, 27);
+		if (in_alt_jump(jump_addr, start, end))
+			return;
+		offset = jump_addr - pc;
+		BUG_ON(offset < -SZ_128M || offset >= SZ_128M);
+		offset >>= 2;
+		buf->reg0i26_format.immediate_h = offset >> 16;
+		buf->reg0i26_format.immediate_l = offset;
+		return;
+	}
+
+	si_l = src->reg1i21_format.immediate_l;
+	si_h = src->reg1i21_format.immediate_h;
+	switch (src->reg1i21_format.opcode) {
+	case bceqz_op: /* bceqz_op = bcnez_op */
+		BUG_ON(buf->reg1i21_format.rj & BIT(4));
+		fallthrough;
+	case beqz_op:
+	case bnez_op:
+		jump_addr = cur_pc + sign_extend((si_h << 16 | si_l) << 2, 22);
+		if (in_alt_jump(jump_addr, start, end))
+			return;
+		offset = jump_addr - pc;
+		BUG_ON(offset < -SZ_4M || offset >= SZ_4M);
+		offset >>= 2;
+		buf->reg1i21_format.immediate_h = offset >> 16;
+		buf->reg1i21_format.immediate_l = offset;
+		return;
+	}
+
+	si = src->reg2i16_format.immediate;
+	switch (src->reg2i16_format.opcode) {
+	case beq_op:
+	case bne_op:
+	case blt_op:
+	case bge_op:
+	case bltu_op:
+	case bgeu_op:
+		jump_addr = cur_pc + sign_extend(si << 2, 17);
+		if (in_alt_jump(jump_addr, start, end))
+			return;
+		offset = jump_addr - pc;
+		BUG_ON(offset < -SZ_128K || offset >= SZ_128K);
+		offset >>= 2;
+		buf->reg2i16_format.immediate = offset;
+		return;
+	}
+}
+
+static int __init_or_module copy_alt_insns(union loongarch_instruction *buf,
+	union loongarch_instruction *dest, union loongarch_instruction *src, int nr)
+{
+	int i;
+
+	for (i = 0; i < nr; i++) {
+		buf[i].word = src[i].word;
+
+		if (is_pc_ins(&src[i])) {
+			pr_err("Not support pcrel instruction at present!");
+			return -EINVAL;
+		}
+
+		if (is_branch_ins(&src[i]) &&
+		    src[i].reg2i16_format.opcode != jirl_op) {
+			recompute_jump(&buf[i], &dest[i], &src[i], src, src + nr);
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * text_poke_early - Update instructions on a live kernel at boot time
+ *
+ * When you use this code to patch more than one byte of an instruction
+ * you need to make sure that other CPUs cannot execute this code in parallel.
+ * Also no thread must be currently preempted in the middle of these
+ * instructions. And on the local CPU you need to be protected again NMI or MCE
+ * handlers seeing an inconsistent instruction while you patch.
+ */
+static void *__init_or_module text_poke_early(union loongarch_instruction *insn,
+			      union loongarch_instruction *buf, unsigned int nr)
+{
+	int i;
+	unsigned long flags;
+
+	local_irq_save(flags);
+
+	for (i = 0; i < nr; i++)
+		insn[i].word = buf[i].word;
+
+	local_irq_restore(flags);
+
+	wbflush();
+	flush_icache_range((unsigned long)insn, (unsigned long)(insn + nr));
+
+	return insn;
+}
+
+/*
+ * Replace instructions with better alternatives for this CPU type. This runs
+ * before SMP is initialized to avoid SMP problems with self modifying code.
+ * This implies that asymmetric systems where APs have less capabilities than
+ * the boot processor are not handled. Tough. Make sure you disable such
+ * features by hand.
+ */
+void __init_or_module apply_alternatives(struct alt_instr *start, struct alt_instr *end)
+{
+	struct alt_instr *a;
+	unsigned int nr_instr, nr_repl, nr_insnbuf;
+	union loongarch_instruction *instr, *replacement;
+	union loongarch_instruction insnbuf[MAX_PATCH_SIZE];
+
+	DPRINTK("alt table %px, -> %px", start, end);
+	/*
+	 * The scan order should be from start to end. A later scanned
+	 * alternative code can overwrite previously scanned alternative code.
+	 * Some kernel functions (e.g. memcpy, memset, etc) use this order to
+	 * patch code.
+	 *
+	 * So be careful if you want to change the scan order to any other
+	 * order.
+	 */
+	for (a = start; a < end; a++) {
+		nr_insnbuf = 0;
+
+		instr = (void *)&a->instr_offset + a->instr_offset;
+		replacement = (void *)&a->replace_offset + a->replace_offset;
+
+		BUG_ON(a->instrlen > sizeof(insnbuf));
+		BUG_ON(a->instrlen & 0x3);
+		BUG_ON(a->replacementlen & 0x3);
+
+		nr_instr = a->instrlen / LOONGARCH_INSN_SIZE;
+		nr_repl = a->replacementlen / LOONGARCH_INSN_SIZE;
+
+		if (!cpu_has(a->feature)) {
+			DPRINTK("feat not exist: %d, old: (%px len: %d), repl: (%px, len: %d)",
+				a->feature, instr, a->instrlen,
+				replacement, a->replacementlen);
+
+			continue;
+		}
+
+		DPRINTK("feat: %d, old: (%px len: %d), repl: (%px, len: %d)",
+			a->feature, instr, a->instrlen,
+			replacement, a->replacementlen);
+
+		DUMP_WORDS(instr, nr_instr, "%px: old_insn: ", instr);
+		DUMP_WORDS(replacement, nr_repl, "%px: rpl_insn: ", replacement);
+
+		copy_alt_insns(insnbuf, instr, replacement, nr_repl);
+		nr_insnbuf = nr_repl;
+
+		if (nr_instr > nr_repl) {
+			add_nops(insnbuf + nr_repl, nr_instr - nr_repl);
+			nr_insnbuf += nr_instr - nr_repl;
+		}
+		DUMP_WORDS(insnbuf, nr_insnbuf, "%px: final_insn: ", instr);
+
+		text_poke_early(instr, insnbuf, nr_insnbuf);
+	}
+}
+
+void __init alternative_instructions(void)
+{
+	apply_alternatives(__alt_instructions, __alt_instructions_end);
+
+	alternatives_patched = 1;
+}

arch/loongarch/kernel/asm-offsets.c

@@ -68,6 +68,9 @@ void output_task_defines(void)
 	OFFSET(TASK_FLAGS, task_struct, flags);
 	OFFSET(TASK_MM, task_struct, mm);
 	OFFSET(TASK_PID, task_struct, pid);
+#if defined(CONFIG_STACKPROTECTOR)
+	OFFSET(TASK_STACK_CANARY, task_struct, stack_canary);
+#endif
 	DEFINE(TASK_STRUCT_SIZE, sizeof(struct task_struct));
 	BLANK();
 }
@@ -257,3 +260,15 @@ void output_smpboot_defines(void)
 	BLANK();
 }
 #endif
+
+#ifdef CONFIG_HIBERNATION
+void output_pbe_defines(void)
+{
+	COMMENT(" Linux struct pbe offsets. ");
+	OFFSET(PBE_ADDRESS, pbe, address);
+	OFFSET(PBE_ORIG_ADDRESS, pbe, orig_address);
+	OFFSET(PBE_NEXT, pbe, next);
+	DEFINE(PBE_SIZE, sizeof(struct pbe));
+	BLANK();
+}
+#endif

arch/loongarch/kernel/efi.c

@@ -28,16 +28,29 @@ static unsigned long efi_nr_tables;
 static unsigned long efi_config_table;
 
 static unsigned long __initdata boot_memmap = EFI_INVALID_TABLE_ADDR;
+static unsigned long __initdata fdt_pointer = EFI_INVALID_TABLE_ADDR;
 
 static efi_system_table_t *efi_systab;
 static efi_config_table_type_t arch_tables[] __initdata = {
 	{LINUX_EFI_BOOT_MEMMAP_GUID,	&boot_memmap,	"MEMMAP" },
+	{DEVICE_TREE_GUID,		&fdt_pointer,	"FDTPTR" },
 	{},
 };
 
+void __init *efi_fdt_pointer(void)
+{
+	if (!efi_systab)
+		return NULL;
+
+	if (fdt_pointer == EFI_INVALID_TABLE_ADDR)
+		return NULL;
+
+	return early_memremap_ro(fdt_pointer, SZ_64K);
+}
+
 void __init efi_runtime_init(void)
 {
-	if (!efi_enabled(EFI_BOOT))
+	if (!efi_enabled(EFI_BOOT) || !efi_systab->runtime)
 		return;
 
 	if (efi_runtime_disabled()) {

arch/loongarch/kernel/env.c

@@ -11,6 +11,7 @@
 #include <asm/early_ioremap.h>
 #include <asm/bootinfo.h>
 #include <asm/loongson.h>
+#include <asm/setup.h>
 
 u64 efi_system_table;
 struct loongson_system_configuration loongson_sysconf;
@@ -27,6 +28,7 @@ void __init init_environ(void)
 		clear_bit(EFI_BOOT, &efi.flags);
 
 	strscpy(boot_command_line, cmdline, COMMAND_LINE_SIZE);
+	strscpy(init_command_line, cmdline, COMMAND_LINE_SIZE);
 	early_memunmap(cmdline, COMMAND_LINE_SIZE);
 
 	efi_system_table = fw_arg2;

arch/loongarch/kernel/fpu.S

@@ -8,6 +8,7 @@
  */
 #include <asm/asm.h>
 #include <asm/asmmacro.h>
+#include <asm/asm-extable.h>
 #include <asm/asm-offsets.h>
 #include <asm/errno.h>
 #include <asm/export.h>
@@ -21,9 +22,7 @@
 
 	.macro	EX insn, reg, src, offs
 .ex\@:	\insn	\reg, \src, \offs
-	.section __ex_table,"a"
-	PTR	.ex\@, fault
-	.previous
+	_asm_extable .ex\@, fault
 	.endm
 
 	.macro sc_save_fp base

arch/loongarch/kernel/ftrace.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+
+#include <linux/init.h>
+#include <linux/ftrace.h>
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+
+#include <asm/asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/cacheflush.h>
+#include <asm/inst.h>
+#include <asm/loongarch.h>
+#include <asm/syscall.h>
+
+#include <asm-generic/sections.h>
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+
+/*
+ * As `call _mcount` follows LoongArch psABI, ra-saved operation and
+ * stack operation can be found before this insn.
+ */
+
+static int ftrace_get_parent_ra_addr(unsigned long insn_addr, int *ra_off)
+{
+	int limit = 32;
+	union loongarch_instruction *insn;
+
+	insn = (union loongarch_instruction *)insn_addr;
+
+	do {
+		insn--;
+		limit--;
+
+		if (is_ra_save_ins(insn))
+			*ra_off = -((1 << 12) - insn->reg2i12_format.immediate);
+
+	} while (!is_stack_alloc_ins(insn) && limit);
+
+	if (!limit)
+		return -EINVAL;
+
+	return 0;
+}
+
+void prepare_ftrace_return(unsigned long self_addr,
+		unsigned long callsite_sp, unsigned long old)
+{
+	int ra_off;
+	unsigned long return_hooker = (unsigned long)&return_to_handler;
+
+	if (unlikely(ftrace_graph_is_dead()))
+		return;
+
+	if (unlikely(atomic_read(&current->tracing_graph_pause)))
+		return;
+
+	if (ftrace_get_parent_ra_addr(self_addr, &ra_off))
+		goto out;
+
+	if (!function_graph_enter(old, self_addr, 0, NULL))
+		*(unsigned long *)(callsite_sp + ra_off) = return_hooker;
+
+	return;
+
+out:
+	ftrace_graph_stop();
+	WARN_ON(1);
+}
+#endif	/* CONFIG_FUNCTION_GRAPH_TRACER */

arch/loongarch/kernel/ftrace_dyn.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Based on arch/arm64/kernel/ftrace.c
+ *
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+
+#include <linux/ftrace.h>
+#include <linux/uaccess.h>
+
+#include <asm/inst.h>
+#include <asm/module.h>
+
+static int ftrace_modify_code(unsigned long pc, u32 old, u32 new, bool validate)
+{
+	u32 replaced;
+
+	if (validate) {
+		if (larch_insn_read((void *)pc, &replaced))
+			return -EFAULT;
+
+		if (replaced != old)
+			return -EINVAL;
+	}
+
+	if (larch_insn_patch_text((void *)pc, new))
+		return -EPERM;
+
+	return 0;
+}
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+
+#ifdef CONFIG_MODULES
+static inline int __get_mod(struct module **mod, unsigned long addr)
+{
+	preempt_disable();
+	*mod = __module_text_address(addr);
+	preempt_enable();
+
+	if (WARN_ON(!(*mod)))
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct plt_entry *get_ftrace_plt(struct module *mod, unsigned long addr)
+{
+	struct plt_entry *plt = mod->arch.ftrace_trampolines;
+
+	if (addr == FTRACE_ADDR)
+		return &plt[FTRACE_PLT_IDX];
+	if (addr == FTRACE_REGS_ADDR &&
+			IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS))
+		return &plt[FTRACE_REGS_PLT_IDX];
+
+	return NULL;
+}
+
+static unsigned long get_plt_addr(struct module *mod, unsigned long addr)
+{
+	struct plt_entry *plt;
+
+	plt = get_ftrace_plt(mod, addr);
+	if (!plt) {
+		pr_err("ftrace: no module PLT for %ps\n", (void *)addr);
+		return -EINVAL;
+	}
+
+	return (unsigned long)plt;
+}
+#endif
+
+int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, unsigned long addr)
+{
+	u32 old, new;
+	unsigned long pc;
+	long offset __maybe_unused;
+
+	pc = rec->ip + LOONGARCH_INSN_SIZE;
+
+#ifdef CONFIG_MODULES
+	offset = (long)pc - (long)addr;
+
+	if (offset < -SZ_128M || offset >= SZ_128M) {
+		int ret;
+		struct module *mod;
+
+		ret = __get_mod(&mod, pc);
+		if (ret)
+			return ret;
+
+		addr = get_plt_addr(mod, addr);
+
+		old_addr = get_plt_addr(mod, old_addr);
+	}
+#endif
+
+	new = larch_insn_gen_bl(pc, addr);
+	old = larch_insn_gen_bl(pc, old_addr);
+
+	return ftrace_modify_code(pc, old, new, true);
+}
+
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */
+
+int ftrace_update_ftrace_func(ftrace_func_t func)
+{
+	u32 new;
+	unsigned long pc;
+
+	pc = (unsigned long)&ftrace_call;
+	new = larch_insn_gen_bl(pc, (unsigned long)func);
+
+	return ftrace_modify_code(pc, 0, new, false);
+}
+
+/*
+ * The compiler has inserted 2 NOPs before the regular function prologue.
+ * T series registers are available and safe because of LoongArch's psABI.
+ *
+ * At runtime, we can replace nop with bl to enable ftrace call and replace bl
+ * with nop to disable ftrace call. The bl requires us to save the original RA
+ * value, so it saves RA at t0 here.
+ *
+ * Details are:
+ *
+ * | Compiled   |       Disabled         |        Enabled         |
+ * +------------+------------------------+------------------------+
+ * | nop        | move     t0, ra        | move     t0, ra        |
+ * | nop        | nop                    | bl       ftrace_caller |
+ * | func_body  | func_body              | func_body              |
+ *
+ * The RA value will be recovered by ftrace_regs_entry, and restored into RA
+ * before returning to the regular function prologue. When a function is not
+ * being traced, the "move t0, ra" is not harmful.
+ */
+
+int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec)
+{
+	u32 old, new;
+	unsigned long pc;
+
+	pc = rec->ip;
+	old = larch_insn_gen_nop();
+	new = larch_insn_gen_move(LOONGARCH_GPR_T0, LOONGARCH_GPR_RA);
+
+	return ftrace_modify_code(pc, old, new, true);
+}
+
+int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
+{
+	u32 old, new;
+	unsigned long pc;
+	long offset __maybe_unused;
+
+	pc = rec->ip + LOONGARCH_INSN_SIZE;
+
+#ifdef CONFIG_MODULES
+	offset = (long)pc - (long)addr;
+
+	if (offset < -SZ_128M || offset >= SZ_128M) {
+		int ret;
+		struct module *mod;
+
+		ret = __get_mod(&mod, pc);
+		if (ret)
+			return ret;
+
+		addr = get_plt_addr(mod, addr);
+	}
+#endif
+
+	old = larch_insn_gen_nop();
+	new = larch_insn_gen_bl(pc, addr);
+
+	return ftrace_modify_code(pc, old, new, true);
+}
+
+int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr)
+{
+	u32 old, new;
+	unsigned long pc;
+	long offset __maybe_unused;
+
+	pc = rec->ip + LOONGARCH_INSN_SIZE;
+
+#ifdef CONFIG_MODULES
+	offset = (long)pc - (long)addr;
+
+	if (offset < -SZ_128M || offset >= SZ_128M) {
+		int ret;
+		struct module *mod;
+
+		ret = __get_mod(&mod, pc);
+		if (ret)
+			return ret;
+
+		addr = get_plt_addr(mod, addr);
+	}
+#endif
+
+	new = larch_insn_gen_nop();
+	old = larch_insn_gen_bl(pc, addr);
+
+	return ftrace_modify_code(pc, old, new, true);
+}
+
+void arch_ftrace_update_code(int command)
+{
+	command |= FTRACE_MAY_SLEEP;
+	ftrace_modify_all_code(command);
+}
+
+int __init ftrace_dyn_arch_init(void)
+{
+	return 0;
+}
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent)
+{
+	unsigned long old;
+	unsigned long return_hooker = (unsigned long)&return_to_handler;
+
+	if (unlikely(atomic_read(&current->tracing_graph_pause)))
+		return;
+
+	old = *parent;
+
+	if (!function_graph_enter(old, self_addr, 0, parent))
+		*parent = return_hooker;
+}
+
+#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
+void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
+		       struct ftrace_ops *op, struct ftrace_regs *fregs)
+{
+	struct pt_regs *regs = &fregs->regs;
+	unsigned long *parent = (unsigned long *)&regs->regs[1];
+
+	prepare_ftrace_return(ip, (unsigned long *)parent);
+}
+#else
+static int ftrace_modify_graph_caller(bool enable)
+{
+	u32 branch, nop;
+	unsigned long pc, func;
+	extern void ftrace_graph_call(void);
+
+	pc = (unsigned long)&ftrace_graph_call;
+	func = (unsigned long)&ftrace_graph_caller;
+
+	nop = larch_insn_gen_nop();
+	branch = larch_insn_gen_b(pc, func);
+
+	if (enable)
+		return ftrace_modify_code(pc, nop, branch, true);
+	else
+		return ftrace_modify_code(pc, branch, nop, true);
+}
+
+int ftrace_enable_ftrace_graph_caller(void)
+{
+	return ftrace_modify_graph_caller(true);
+}
+
+int ftrace_disable_ftrace_graph_caller(void)
+{
+	return ftrace_modify_graph_caller(false);
+}
+#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */

arch/loongarch/kernel/inst.c

@@ -2,8 +2,135 @@
 /*
  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
  */
+#include <linux/sizes.h>
+#include <linux/uaccess.h>
+
+#include <asm/cacheflush.h>
 #include <asm/inst.h>
 
+static DEFINE_RAW_SPINLOCK(patch_lock);
+
+int larch_insn_read(void *addr, u32 *insnp)
+{
+	int ret;
+	u32 val;
+
+	ret = copy_from_kernel_nofault(&val, addr, LOONGARCH_INSN_SIZE);
+	if (!ret)
+		*insnp = val;
+
+	return ret;
+}
+
+int larch_insn_write(void *addr, u32 insn)
+{
+	int ret;
+	unsigned long flags = 0;
+
+	raw_spin_lock_irqsave(&patch_lock, flags);
+	ret = copy_to_kernel_nofault(addr, &insn, LOONGARCH_INSN_SIZE);
+	raw_spin_unlock_irqrestore(&patch_lock, flags);
+
+	return ret;
+}
+
+int larch_insn_patch_text(void *addr, u32 insn)
+{
+	int ret;
+	u32 *tp = addr;
+
+	if ((unsigned long)tp & 3)
+		return -EINVAL;
+
+	ret = larch_insn_write(tp, insn);
+	if (!ret)
+		flush_icache_range((unsigned long)tp,
+				   (unsigned long)tp + LOONGARCH_INSN_SIZE);
+
+	return ret;
+}
+
+u32 larch_insn_gen_nop(void)
+{
+	return INSN_NOP;
+}
+
+u32 larch_insn_gen_b(unsigned long pc, unsigned long dest)
+{
+	long offset = dest - pc;
+	unsigned int immediate_l, immediate_h;
+	union loongarch_instruction insn;
+
+	if ((offset & 3) || offset < -SZ_128M || offset >= SZ_128M) {
+		pr_warn("The generated b instruction is out of range.\n");
+		return INSN_BREAK;
+	}
+
+	offset >>= 2;
+
+	immediate_l = offset & 0xffff;
+	offset >>= 16;
+	immediate_h = offset & 0x3ff;
+
+	insn.reg0i26_format.opcode = b_op;
+	insn.reg0i26_format.immediate_l = immediate_l;
+	insn.reg0i26_format.immediate_h = immediate_h;
+
+	return insn.word;
+}
+
+u32 larch_insn_gen_bl(unsigned long pc, unsigned long dest)
+{
+	long offset = dest - pc;
+	unsigned int immediate_l, immediate_h;
+	union loongarch_instruction insn;
+
+	if ((offset & 3) || offset < -SZ_128M || offset >= SZ_128M) {
+		pr_warn("The generated bl instruction is out of range.\n");
+		return INSN_BREAK;
+	}
+
+	offset >>= 2;
+
+	immediate_l = offset & 0xffff;
+	offset >>= 16;
+	immediate_h = offset & 0x3ff;
+
+	insn.reg0i26_format.opcode = bl_op;
+	insn.reg0i26_format.immediate_l = immediate_l;
+	insn.reg0i26_format.immediate_h = immediate_h;
+
+	return insn.word;
+}
+
+u32 larch_insn_gen_or(enum loongarch_gpr rd, enum loongarch_gpr rj, enum loongarch_gpr rk)
+{
+	union loongarch_instruction insn;
+
+	insn.reg3_format.opcode = or_op;
+	insn.reg3_format.rd = rd;
+	insn.reg3_format.rj = rj;
+	insn.reg3_format.rk = rk;
+
+	return insn.word;
+}
+
+u32 larch_insn_gen_move(enum loongarch_gpr rd, enum loongarch_gpr rj)
+{
+	return larch_insn_gen_or(rd, rj, 0);
+}
+
+u32 larch_insn_gen_lu12iw(enum loongarch_gpr rd, int imm)
+{
+	union loongarch_instruction insn;
+
+	insn.reg1i20_format.opcode = lu12iw_op;
+	insn.reg1i20_format.rd = rd;
+	insn.reg1i20_format.immediate = imm;
+
+	return insn.word;
+}
+
 u32 larch_insn_gen_lu32id(enum loongarch_gpr rd, int imm)
 {
 	union loongarch_instruction insn;

arch/loongarch/kernel/mcount.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * LoongArch specific _mcount support
+ *
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/export.h>
+#include <asm/ftrace.h>
+#include <asm/regdef.h>
+#include <asm/stackframe.h>
+
+	.text
+
+#define MCOUNT_S0_OFFSET	(0)
+#define MCOUNT_RA_OFFSET	(SZREG)
+#define MCOUNT_STACK_SIZE	(2 * SZREG)
+
+	.macro MCOUNT_SAVE_REGS
+	PTR_ADDI	sp, sp, -MCOUNT_STACK_SIZE
+	PTR_S		s0, sp, MCOUNT_S0_OFFSET
+	PTR_S		ra, sp, MCOUNT_RA_OFFSET
+	move		s0, a0
+	.endm
+
+	.macro MCOUNT_RESTORE_REGS
+	move		a0, s0
+	PTR_L		ra, sp, MCOUNT_RA_OFFSET
+	PTR_L		s0, sp, MCOUNT_S0_OFFSET
+	PTR_ADDI	sp, sp, MCOUNT_STACK_SIZE
+	.endm
+
+SYM_FUNC_START(_mcount)
+	la.pcrel	t1, ftrace_stub
+	la.pcrel	t2, ftrace_trace_function	/* Prepare t2 for (1) */
+	PTR_L		t2, t2, 0
+	beq		t1, t2, fgraph_trace
+
+	MCOUNT_SAVE_REGS
+
+	move		a0, ra				/* arg0: self return address */
+	move		a1, s0				/* arg1: parent's return address */
+	jirl		ra, t2, 0			/* (1) call *ftrace_trace_function */
+
+	MCOUNT_RESTORE_REGS
+
+fgraph_trace:
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+	la.pcrel	t1, ftrace_stub
+	la.pcrel	t3, ftrace_graph_return
+	PTR_L		t3, t3, 0
+	bne		t1, t3, ftrace_graph_caller
+	la.pcrel	t1, ftrace_graph_entry_stub
+	la.pcrel	t3, ftrace_graph_entry
+	PTR_L		t3, t3, 0
+	bne		t1, t3, ftrace_graph_caller
+#endif
+
+SYM_INNER_LABEL(ftrace_stub, SYM_L_GLOBAL)
+	jr		ra
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+SYM_INNER_LABEL(ftrace_graph_func, SYM_L_GLOBAL)
+	bl		ftrace_stub
+#endif
+SYM_FUNC_END(_mcount)
+EXPORT_SYMBOL(_mcount)
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+SYM_FUNC_START(ftrace_graph_caller)
+	MCOUNT_SAVE_REGS
+
+	PTR_ADDI	a0, ra, -4			/* arg0: Callsite self return addr */
+	PTR_ADDI	a1, sp, MCOUNT_STACK_SIZE	/* arg1: Callsite sp */
+	move		a2, s0				/* arg2: Callsite parent ra */
+	bl		prepare_ftrace_return
+
+	MCOUNT_RESTORE_REGS
+	jr		ra
+SYM_FUNC_END(ftrace_graph_caller)
+
+SYM_FUNC_START(return_to_handler)
+	PTR_ADDI	sp, sp, -2 * SZREG
+	PTR_S		a0, sp, 0
+	PTR_S		a1, sp, SZREG
+
+	bl		ftrace_return_to_handler
+
+	/* Restore the real parent address: a0 -> ra */
+	move		ra, a0
+
+	PTR_L		a0, sp, 0
+	PTR_L		a1, sp, SZREG
+	PTR_ADDI	sp, sp, 2 * SZREG
+	jr		ra
+SYM_FUNC_END(return_to_handler)
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */

arch/loongarch/kernel/mcount_dyn.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/export.h>
+#include <asm/ftrace.h>
+#include <asm/regdef.h>
+#include <asm/stackframe.h>
+
+	.text
+/*
+ * Due to -fpatchable-function-entry=2: the compiler inserted 2 NOPs before the
+ * regular C function prologue. When PC arrived here, the last 2 instructions
+ * are as follows:
+ * 	move		t0, ra
+ * 	bl		callsite (for modules, callsite is a tramplione)
+ *
+ * modules trampoline is as follows:
+ * 	lu12i.w		t1, callsite[31:12]
+ * 	lu32i.d		t1, callsite[51:32]
+ * 	lu52i.d		t1, t1, callsite[63:52]
+ * 	jirl		zero, t1, callsite[11:0] >> 2
+ *
+ * See arch/loongarch/kernel/ftrace_dyn.c for details. Here, pay attention to
+ * that the T series regs are available and safe because each C functions
+ * follows the LoongArch's psABI as well.
+ */
+
+	.macro  ftrace_regs_entry allregs=0
+	PTR_ADDI	sp, sp, -PT_SIZE
+	PTR_S		t0, sp, PT_R1  /* Save parent ra at PT_R1(RA) */
+	PTR_S		a0, sp, PT_R4
+	PTR_S		a1, sp, PT_R5
+	PTR_S		a2, sp, PT_R6
+	PTR_S		a3, sp, PT_R7
+	PTR_S		a4, sp, PT_R8
+	PTR_S		a5, sp, PT_R9
+	PTR_S		a6, sp, PT_R10
+	PTR_S		a7, sp, PT_R11
+	PTR_S		fp, sp, PT_R22
+	.if \allregs
+	PTR_S		tp, sp, PT_R2
+	PTR_S		t0, sp, PT_R12
+	PTR_S		t1, sp, PT_R13
+	PTR_S		t2, sp, PT_R14
+	PTR_S		t3, sp, PT_R15
+	PTR_S		t4, sp, PT_R16
+	PTR_S		t5, sp, PT_R17
+	PTR_S		t6, sp, PT_R18
+	PTR_S		t7, sp, PT_R19
+	PTR_S		t8, sp, PT_R20
+	PTR_S		u0, sp, PT_R21
+	PTR_S		s0, sp, PT_R23
+	PTR_S		s1, sp, PT_R24
+	PTR_S		s2, sp, PT_R25
+	PTR_S		s3, sp, PT_R26
+	PTR_S		s4, sp, PT_R27
+	PTR_S		s5, sp, PT_R28
+	PTR_S		s6, sp, PT_R29
+	PTR_S		s7, sp, PT_R30
+	PTR_S		s8, sp, PT_R31
+	/* Clear it for later use as a flag sometimes. */
+	PTR_S		zero, sp, PT_R0
+	.endif
+	PTR_S		ra, sp, PT_ERA /* Save trace function ra at PT_ERA */
+	PTR_ADDI	t8, sp, PT_SIZE
+	PTR_S		t8, sp, PT_R3
+	.endm
+
+SYM_FUNC_START(ftrace_stub)
+	jr		ra
+SYM_FUNC_END(ftrace_stub)
+
+SYM_CODE_START(ftrace_common)
+	PTR_ADDI	a0, ra, -8	/* arg0: ip */
+	move		a1, t0		/* arg1: parent_ip */
+	la.pcrel	t1, function_trace_op
+	PTR_L		a2, t1, 0	/* arg2: op */
+	move		a3, sp		/* arg3: regs */
+
+SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL)
+	bl		ftrace_stub
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL)
+	nop				/* b ftrace_graph_caller */
+#endif
+
+/*
+ * As we didn't use S series regs in this assmembly code and all calls
+ * are C function which will save S series regs by themselves, there is
+ * no need to restore S series regs. The T series is available and safe
+ * at the callsite, so there is no need to restore the T series regs.
+ */
+ftrace_common_return:
+	PTR_L		ra, sp, PT_R1
+	PTR_L		a0, sp, PT_R4
+	PTR_L		a1, sp, PT_R5
+	PTR_L		a2, sp, PT_R6
+	PTR_L		a3, sp, PT_R7
+	PTR_L		a4, sp, PT_R8
+	PTR_L		a5, sp, PT_R9
+	PTR_L		a6, sp, PT_R10
+	PTR_L		a7, sp, PT_R11
+	PTR_L		fp, sp, PT_R22
+	PTR_L		t0, sp, PT_ERA
+	PTR_ADDI	sp, sp, PT_SIZE
+	jr		t0
+SYM_CODE_END(ftrace_common)
+
+SYM_CODE_START(ftrace_caller)
+	ftrace_regs_entry allregs=0
+	b		ftrace_common
+SYM_CODE_END(ftrace_caller)
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+SYM_CODE_START(ftrace_regs_caller)
+	ftrace_regs_entry allregs=1
+	b		ftrace_common
+SYM_CODE_END(ftrace_regs_caller)
+#endif
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+SYM_CODE_START(ftrace_graph_caller)
+	PTR_L		a0, sp, PT_ERA
+	PTR_ADDI	a0, a0, -8	/* arg0: self_addr */
+	PTR_ADDI	a1, sp, PT_R1	/* arg1: parent */
+	bl		prepare_ftrace_return
+	b		ftrace_common_return
+SYM_CODE_END(ftrace_graph_caller)
+
+SYM_CODE_START(return_to_handler)
+	/* Save return value regs */
+	PTR_ADDI 	sp, sp, -2 * SZREG
+	PTR_S		a0, sp, 0
+	PTR_S		a1, sp, SZREG
+
+	move		a0, zero
+	bl		ftrace_return_to_handler
+	move		ra, a0
+
+	/* Restore return value regs */
+	PTR_L		a0, sp, 0
+	PTR_L		a1, sp, SZREG
+	PTR_ADDI 	sp, sp, 2 * SZREG
+
+	jr		ra
+SYM_CODE_END(return_to_handler)
+#endif

arch/loongarch/kernel/module-sections.c

@@ -6,18 +6,19 @@
 #include <linux/elf.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/ftrace.h>
 
-Elf_Addr module_emit_got_entry(struct module *mod, Elf_Addr val)
+Elf_Addr module_emit_got_entry(struct module *mod, Elf_Shdr *sechdrs, Elf_Addr val)
 {
 	struct mod_section *got_sec = &mod->arch.got;
 	int i = got_sec->num_entries;
-	struct got_entry *got = get_got_entry(val, got_sec);
+	struct got_entry *got = get_got_entry(val, sechdrs, got_sec);
 
 	if (got)
 		return (Elf_Addr)got;
 
 	/* There is no GOT entry for val yet, create a new one. */
-	got = (struct got_entry *)got_sec->shdr->sh_addr;
+	got = (struct got_entry *)sechdrs[got_sec->shndx].sh_addr;
 	got[i] = emit_got_entry(val);
 
 	got_sec->num_entries++;
@@ -33,12 +34,12 @@ Elf_Addr module_emit_got_entry(struct module *mod, Elf_Addr val)
 	return (Elf_Addr)&got[i];
 }
 
-Elf_Addr module_emit_plt_entry(struct module *mod, Elf_Addr val)
+Elf_Addr module_emit_plt_entry(struct module *mod, Elf_Shdr *sechdrs, Elf_Addr val)
 {
 	int nr;
 	struct mod_section *plt_sec = &mod->arch.plt;
 	struct mod_section *plt_idx_sec = &mod->arch.plt_idx;
-	struct plt_entry *plt = get_plt_entry(val, plt_sec, plt_idx_sec);
+	struct plt_entry *plt = get_plt_entry(val, sechdrs, plt_sec, plt_idx_sec);
 	struct plt_idx_entry *plt_idx;
 
 	if (plt)
@@ -47,9 +48,9 @@ Elf_Addr module_emit_plt_entry(struct module *mod, Elf_Addr val)
 	nr = plt_sec->num_entries;
 
 	/* There is no duplicate entry, create a new one */
-	plt = (struct plt_entry *)plt_sec->shdr->sh_addr;
+	plt = (struct plt_entry *)sechdrs[plt_sec->shndx].sh_addr;
 	plt[nr] = emit_plt_entry(val);
-	plt_idx = (struct plt_idx_entry *)plt_idx_sec->shdr->sh_addr;
+	plt_idx = (struct plt_idx_entry *)sechdrs[plt_idx_sec->shndx].sh_addr;
 	plt_idx[nr] = emit_plt_idx_entry(val);
 
 	plt_sec->num_entries++;
@@ -103,28 +104,31 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 			      char *secstrings, struct module *mod)
 {
 	unsigned int i, num_plts = 0, num_gots = 0;
+	Elf_Shdr *got_sec, *plt_sec, *plt_idx_sec, *tramp = NULL;
 
 	/*
 	 * Find the empty .plt sections.
 	 */
 	for (i = 0; i < ehdr->e_shnum; i++) {
 		if (!strcmp(secstrings + sechdrs[i].sh_name, ".got"))
-			mod->arch.got.shdr = sechdrs + i;
+			mod->arch.got.shndx = i;
 		else if (!strcmp(secstrings + sechdrs[i].sh_name, ".plt"))
-			mod->arch.plt.shdr = sechdrs + i;
+			mod->arch.plt.shndx = i;
 		else if (!strcmp(secstrings + sechdrs[i].sh_name, ".plt.idx"))
-			mod->arch.plt_idx.shdr = sechdrs + i;
+			mod->arch.plt_idx.shndx = i;
+		else if (!strcmp(secstrings + sechdrs[i].sh_name, ".ftrace_trampoline"))
+			tramp = sechdrs + i;
 	}
 
-	if (!mod->arch.got.shdr) {
+	if (!mod->arch.got.shndx) {
 		pr_err("%s: module GOT section(s) missing\n", mod->name);
 		return -ENOEXEC;
 	}
-	if (!mod->arch.plt.shdr) {
+	if (!mod->arch.plt.shndx) {
 		pr_err("%s: module PLT section(s) missing\n", mod->name);
 		return -ENOEXEC;
 	}
-	if (!mod->arch.plt_idx.shdr) {
+	if (!mod->arch.plt_idx.shndx) {
 		pr_err("%s: module PLT.IDX section(s) missing\n", mod->name);
 		return -ENOEXEC;
 	}
@@ -145,26 +149,36 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 		count_max_entries(relas, num_rela, &num_plts, &num_gots);
 	}
 
-	mod->arch.got.shdr->sh_type = SHT_NOBITS;
-	mod->arch.got.shdr->sh_flags = SHF_ALLOC;
-	mod->arch.got.shdr->sh_addralign = L1_CACHE_BYTES;
-	mod->arch.got.shdr->sh_size = (num_gots + 1) * sizeof(struct got_entry);
+	got_sec = sechdrs + mod->arch.got.shndx;
+	got_sec->sh_type = SHT_NOBITS;
+	got_sec->sh_flags = SHF_ALLOC;
+	got_sec->sh_addralign = L1_CACHE_BYTES;
+	got_sec->sh_size = (num_gots + 1) * sizeof(struct got_entry);
 	mod->arch.got.num_entries = 0;
 	mod->arch.got.max_entries = num_gots;
 
-	mod->arch.plt.shdr->sh_type = SHT_NOBITS;
-	mod->arch.plt.shdr->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
-	mod->arch.plt.shdr->sh_addralign = L1_CACHE_BYTES;
-	mod->arch.plt.shdr->sh_size = (num_plts + 1) * sizeof(struct plt_entry);
+	plt_sec = sechdrs + mod->arch.plt.shndx;
+	plt_sec->sh_type = SHT_NOBITS;
+	plt_sec->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
+	plt_sec->sh_addralign = L1_CACHE_BYTES;
+	plt_sec->sh_size = (num_plts + 1) * sizeof(struct plt_entry);
 	mod->arch.plt.num_entries = 0;
 	mod->arch.plt.max_entries = num_plts;
 
-	mod->arch.plt_idx.shdr->sh_type = SHT_NOBITS;
-	mod->arch.plt_idx.shdr->sh_flags = SHF_ALLOC;
-	mod->arch.plt_idx.shdr->sh_addralign = L1_CACHE_BYTES;
-	mod->arch.plt_idx.shdr->sh_size = (num_plts + 1) * sizeof(struct plt_idx_entry);
+	plt_idx_sec = sechdrs + mod->arch.plt_idx.shndx;
+	plt_idx_sec->sh_type = SHT_NOBITS;
+	plt_idx_sec->sh_flags = SHF_ALLOC;
+	plt_idx_sec->sh_addralign = L1_CACHE_BYTES;
+	plt_idx_sec->sh_size = (num_plts + 1) * sizeof(struct plt_idx_entry);
 	mod->arch.plt_idx.num_entries = 0;
 	mod->arch.plt_idx.max_entries = num_plts;
 
+	if (tramp) {
+		tramp->sh_type = SHT_NOBITS;
+		tramp->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
+		tramp->sh_addralign = __alignof__(struct plt_entry);
+		tramp->sh_size = NR_FTRACE_PLTS * sizeof(struct plt_entry);
+	}
+
 	return 0;
 }

arch/loongarch/kernel/module.c

@@ -15,8 +15,11 @@
 #include <linux/vmalloc.h>
 #include <linux/slab.h>
 #include <linux/fs.h>
+#include <linux/ftrace.h>
 #include <linux/string.h>
 #include <linux/kernel.h>
+#include <asm/alternative.h>
+#include <asm/inst.h>
 
 static int rela_stack_push(s64 stack_value, s64 *rela_stack, size_t *rela_stack_top)
 {
@@ -98,16 +101,17 @@ static int apply_r_larch_sop_push_dup(struct module *mod, u32 *location, Elf_Add
 	return 0;
 }
 
-static int apply_r_larch_sop_push_plt_pcrel(struct module *mod, u32 *location, Elf_Addr v,
+static int apply_r_larch_sop_push_plt_pcrel(struct module *mod,
+			Elf_Shdr *sechdrs, u32 *location, Elf_Addr v,
 			s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
 {
 	ptrdiff_t offset = (void *)v - (void *)location;
 
 	if (offset >= SZ_128M)
-		v = module_emit_plt_entry(mod, v);
+		v = module_emit_plt_entry(mod, sechdrs, v);
 
 	if (offset < -SZ_128M)
-		v = module_emit_plt_entry(mod, v);
+		v = module_emit_plt_entry(mod, sechdrs, v);
 
 	return apply_r_larch_sop_push_pcrel(mod, location, v, rela_stack, rela_stack_top, type);
 }
@@ -271,17 +275,18 @@ static int apply_r_larch_add_sub(struct module *mod, u32 *location, Elf_Addr v,
 	}
 }
 
-static int apply_r_larch_b26(struct module *mod, u32 *location, Elf_Addr v,
+static int apply_r_larch_b26(struct module *mod,
+			Elf_Shdr *sechdrs, u32 *location, Elf_Addr v,
 			s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
 {
 	ptrdiff_t offset = (void *)v - (void *)location;
 	union loongarch_instruction *insn = (union loongarch_instruction *)location;
 
 	if (offset >= SZ_128M)
-		v = module_emit_plt_entry(mod, v);
+		v = module_emit_plt_entry(mod, sechdrs, v);
 
 	if (offset < -SZ_128M)
-		v = module_emit_plt_entry(mod, v);
+		v = module_emit_plt_entry(mod, sechdrs, v);
 
 	offset = (void *)v - (void *)location;
 
@@ -338,10 +343,11 @@ static int apply_r_larch_pcala(struct module *mod, u32 *location, Elf_Addr v,
 	return 0;
 }
 
-static int apply_r_larch_got_pc(struct module *mod, u32 *location, Elf_Addr v,
+static int apply_r_larch_got_pc(struct module *mod,
+			Elf_Shdr *sechdrs, u32 *location, Elf_Addr v,
 			s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
 {
-	Elf_Addr got = module_emit_got_entry(mod, v);
+	Elf_Addr got = module_emit_got_entry(mod, sechdrs, v);
 
 	if (!got)
 		return -EINVAL;
@@ -386,13 +392,10 @@ static reloc_rela_handler reloc_rela_handlers[] = {
 	[R_LARCH_SOP_PUSH_PCREL]			     = apply_r_larch_sop_push_pcrel,
 	[R_LARCH_SOP_PUSH_ABSOLUTE]			     = apply_r_larch_sop_push_absolute,
 	[R_LARCH_SOP_PUSH_DUP]				     = apply_r_larch_sop_push_dup,
-	[R_LARCH_SOP_PUSH_PLT_PCREL]			     = apply_r_larch_sop_push_plt_pcrel,
 	[R_LARCH_SOP_SUB ... R_LARCH_SOP_IF_ELSE] 	     = apply_r_larch_sop,
 	[R_LARCH_SOP_POP_32_S_10_5 ... R_LARCH_SOP_POP_32_U] = apply_r_larch_sop_imm_field,
 	[R_LARCH_ADD32 ... R_LARCH_SUB64]		     = apply_r_larch_add_sub,
-	[R_LARCH_B26]					     = apply_r_larch_b26,
 	[R_LARCH_PCALA_HI20...R_LARCH_PCALA64_HI12]	     = apply_r_larch_pcala,
-	[R_LARCH_GOT_PC_HI20...R_LARCH_GOT_PC_LO12]	     = apply_r_larch_got_pc,
 };
 
 int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
@@ -443,7 +446,22 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
 		       sym->st_value, rel[i].r_addend, (u64)location);
 
 		v = sym->st_value + rel[i].r_addend;
-		err = handler(mod, location, v, rela_stack, &rela_stack_top, type);
+		switch (type) {
+		case R_LARCH_B26:
+			err = apply_r_larch_b26(mod, sechdrs, location,
+						     v, rela_stack, &rela_stack_top, type);
+			break;
+		case R_LARCH_GOT_PC_HI20...R_LARCH_GOT_PC_LO12:
+			err = apply_r_larch_got_pc(mod, sechdrs, location,
+						     v, rela_stack, &rela_stack_top, type);
+			break;
+		case R_LARCH_SOP_PUSH_PLT_PCREL:
+			err = apply_r_larch_sop_push_plt_pcrel(mod, sechdrs, location,
+						     v, rela_stack, &rela_stack_top, type);
+			break;
+		default:
+			err = handler(mod, location, v, rela_stack, &rela_stack_top, type);
+		}
 		if (err)
 			return err;
 	}
@@ -456,3 +474,36 @@ void *module_alloc(unsigned long size)
 	return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
 			GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE, __builtin_return_address(0));
 }
+
+static void module_init_ftrace_plt(const Elf_Ehdr *hdr,
+				   const Elf_Shdr *sechdrs, struct module *mod)
+{
+#ifdef CONFIG_DYNAMIC_FTRACE
+	struct plt_entry *ftrace_plts;
+
+	ftrace_plts = (void *)sechdrs->sh_addr;
+
+	ftrace_plts[FTRACE_PLT_IDX] = emit_plt_entry(FTRACE_ADDR);
+
+	if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS))
+		ftrace_plts[FTRACE_REGS_PLT_IDX] = emit_plt_entry(FTRACE_REGS_ADDR);
+
+	mod->arch.ftrace_trampolines = ftrace_plts;
+#endif
+}
+
+int module_finalize(const Elf_Ehdr *hdr,
+		    const Elf_Shdr *sechdrs, struct module *mod)
+{
+	const Elf_Shdr *s, *se;
+	const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+
+	for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) {
+		if (!strcmp(".altinstructions", secstrs + s->sh_name))
+			apply_alternatives((void *)s->sh_addr, (void *)s->sh_addr + s->sh_size);
+		if (!strcmp(".ftrace_trampoline", secstrs + s->sh_name))
+			module_init_ftrace_plt(hdr, s, mod);
+	}
+
+	return 0;
+}

arch/loongarch/kernel/numa.c

@@ -388,6 +388,21 @@ static void __init numa_default_distance(void)
 	}
 }
 
+/*
+ * fake_numa_init() - For Non-ACPI systems
+ * Return: 0 on success, -errno on failure.
+ */
+static int __init fake_numa_init(void)
+{
+	phys_addr_t start = memblock_start_of_DRAM();
+	phys_addr_t end = memblock_end_of_DRAM() - 1;
+
+	node_set(0, numa_nodes_parsed);
+	pr_info("Faking a node at [mem %pap-%pap]\n", &start, &end);
+
+	return numa_add_memblk(0, start, end + 1);
+}
+
 int __init init_numa_memory(void)
 {
 	int i;
@@ -404,7 +419,7 @@ int __init init_numa_memory(void)
 	memset(&numa_meminfo, 0, sizeof(numa_meminfo));
 
 	/* Parse SRAT and SLIT if provided by firmware. */
-	ret = acpi_numa_init();
+	ret = acpi_disabled ? fake_numa_init() : acpi_numa_init();
 	if (ret < 0)
 		return ret;
 

arch/loongarch/kernel/process.c

@@ -47,6 +47,12 @@
 #include <asm/unwind.h>
 #include <asm/vdso.h>
 
+#ifdef CONFIG_STACKPROTECTOR
+#include <linux/stackprotector.h>
+unsigned long __stack_chk_guard __read_mostly;
+EXPORT_SYMBOL(__stack_chk_guard);
+#endif
+
 /*
  * Idle related variables and functions
  */

arch/loongarch/kernel/reset.c

@@ -15,6 +15,7 @@
 #include <acpi/reboot.h>
 #include <asm/idle.h>
 #include <asm/loongarch.h>
+#include <asm/loongson.h>
 
 void (*pm_power_off)(void);
 EXPORT_SYMBOL(pm_power_off);
@@ -41,6 +42,10 @@ void machine_power_off(void)
 #ifdef CONFIG_SMP
 	preempt_disable();
 	smp_send_stop();
+#endif
+#ifdef CONFIG_PM
+	if (!acpi_disabled)
+		enable_pci_wakeup();
 #endif
 	do_kernel_power_off();
 #ifdef CONFIG_EFI

arch/loongarch/kernel/setup.c

@@ -28,10 +28,16 @@
 #include <linux/sizes.h>
 #include <linux/device.h>
 #include <linux/dma-map-ops.h>
+#include <linux/libfdt.h>
+#include <linux/of_fdt.h>
+#include <linux/of_address.h>
+#include <linux/suspend.h>
 #include <linux/swiotlb.h>
 
 #include <asm/addrspace.h>
+#include <asm/alternative.h>
 #include <asm/bootinfo.h>
+#include <asm/bugs.h>
 #include <asm/cache.h>
 #include <asm/cpu.h>
 #include <asm/dma.h>
@@ -67,6 +73,7 @@ static const char dmi_empty_string[] = "        ";
  *
  * These are initialized so they are in the .data section
  */
+char init_command_line[COMMAND_LINE_SIZE] __initdata;
 
 static int num_standard_resources;
 static struct resource *standard_resources;
@@ -80,6 +87,11 @@ const char *get_system_type(void)
 	return "generic-loongson-machine";
 }
 
+void __init check_bugs(void)
+{
+	alternative_instructions();
+}
+
 static const char *dmi_string_parse(const struct dmi_header *dm, u8 s)
 {
 	const u8 *bp = ((u8 *) dm) + dm->length;
@@ -246,6 +258,58 @@ static void __init arch_parse_crashkernel(void)
 #endif
 }
 
+static void __init fdt_setup(void)
+{
+#ifdef CONFIG_OF_EARLY_FLATTREE
+	void *fdt_pointer;
+
+	/* ACPI-based systems do not require parsing fdt */
+	if (acpi_os_get_root_pointer())
+		return;
+
+	/* Look for a device tree configuration table entry */
+	fdt_pointer = efi_fdt_pointer();
+	if (!fdt_pointer || fdt_check_header(fdt_pointer))
+		return;
+
+	early_init_dt_scan(fdt_pointer);
+	early_init_fdt_reserve_self();
+
+	max_low_pfn = PFN_PHYS(memblock_end_of_DRAM());
+#endif
+}
+
+static void __init bootcmdline_init(char **cmdline_p)
+{
+	/*
+	 * If CONFIG_CMDLINE_FORCE is enabled then initializing the command line
+	 * is trivial - we simply use the built-in command line unconditionally &
+	 * unmodified.
+	 */
+	if (IS_ENABLED(CONFIG_CMDLINE_FORCE)) {
+		strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
+		goto out;
+	}
+
+#ifdef CONFIG_OF_FLATTREE
+	/*
+	 * If CONFIG_CMDLINE_BOOTLOADER is enabled and we are in FDT-based system,
+	 * the boot_command_line will be overwritten by early_init_dt_scan_chosen().
+	 * So we need to append init_command_line (the original copy of boot_command_line)
+	 * to boot_command_line.
+	 */
+	if (initial_boot_params) {
+		if (boot_command_line[0])
+			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
+
+		strlcat(boot_command_line, init_command_line, COMMAND_LINE_SIZE);
+	}
+#endif
+
+out:
+	*cmdline_p = boot_command_line;
+}
+
 void __init platform_init(void)
 {
 	arch_reserve_vmcore();
@@ -258,6 +322,7 @@ void __init platform_init(void)
 	acpi_gbl_use_default_register_widths = false;
 	acpi_boot_table_init();
 #endif
+	unflatten_and_copy_device_tree();
 
 #ifdef CONFIG_NUMA
 	init_numa_memory();
@@ -290,6 +355,8 @@ static void __init arch_mem_init(char **cmdline_p)
 
 	check_kernel_sections_mem();
 
+	early_init_fdt_scan_reserved_mem();
+
 	/*
 	 * In order to reduce the possibility of kernel panic when failed to
 	 * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate
@@ -304,6 +371,10 @@ static void __init arch_mem_init(char **cmdline_p)
 
 	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
 
+	/* Reserve for hibernation. */
+	register_nosave_region(PFN_DOWN(__pa_symbol(&__nosave_begin)),
+				   PFN_UP(__pa_symbol(&__nosave_end)));
+
 	memblock_dump_all();
 
 	early_memtest(PFN_PHYS(ARCH_PFN_OFFSET), PFN_PHYS(max_low_pfn));
@@ -363,6 +434,81 @@ static void __init resource_init(void)
 #endif
 }
 
+static int __init add_legacy_isa_io(struct fwnode_handle *fwnode,
+				resource_size_t hw_start, resource_size_t size)
+{
+	int ret = 0;
+	unsigned long vaddr;
+	struct logic_pio_hwaddr *range;
+
+	range = kzalloc(sizeof(*range), GFP_ATOMIC);
+	if (!range)
+		return -ENOMEM;
+
+	range->fwnode = fwnode;
+	range->size = size = round_up(size, PAGE_SIZE);
+	range->hw_start = hw_start;
+	range->flags = LOGIC_PIO_CPU_MMIO;
+
+	ret = logic_pio_register_range(range);
+	if (ret) {
+		kfree(range);
+		return ret;
+	}
+
+	/* Legacy ISA must placed at the start of PCI_IOBASE */
+	if (range->io_start != 0) {
+		logic_pio_unregister_range(range);
+		kfree(range);
+		return -EINVAL;
+	}
+
+	vaddr = (unsigned long)(PCI_IOBASE + range->io_start);
+	ioremap_page_range(vaddr, vaddr + size, hw_start, pgprot_device(PAGE_KERNEL));
+
+	return 0;
+}
+
+static __init int arch_reserve_pio_range(void)
+{
+	struct device_node *np;
+
+	for_each_node_by_name(np, "isa") {
+		struct of_range range;
+		struct of_range_parser parser;
+
+		pr_info("ISA Bridge: %pOF\n", np);
+
+		if (of_range_parser_init(&parser, np)) {
+			pr_info("Failed to parse resources.\n");
+			of_node_put(np);
+			break;
+		}
+
+		for_each_of_range(&parser, &range) {
+			switch (range.flags & IORESOURCE_TYPE_BITS) {
+			case IORESOURCE_IO:
+				pr_info(" IO 0x%016llx..0x%016llx  ->  0x%016llx\n",
+					range.cpu_addr,
+					range.cpu_addr + range.size - 1,
+					range.bus_addr);
+				if (add_legacy_isa_io(&np->fwnode, range.cpu_addr, range.size))
+					pr_warn("Failed to reserve legacy IO in Logic PIO\n");
+				break;
+			case IORESOURCE_MEM:
+				pr_info(" MEM 0x%016llx..0x%016llx  ->  0x%016llx\n",
+					range.cpu_addr,
+					range.cpu_addr + range.size - 1,
+					range.bus_addr);
+				break;
+			}
+		}
+	}
+
+	return 0;
+}
+arch_initcall(arch_reserve_pio_range);
+
 static int __init reserve_memblock_reserved_regions(void)
 {
 	u64 i, j;
@@ -415,12 +561,13 @@ static void __init prefill_possible_map(void)
 void __init setup_arch(char **cmdline_p)
 {
 	cpu_probe();
-	*cmdline_p = boot_command_line;
 
 	init_environ();
 	efi_init();
+	fdt_setup();
 	memblock_init();
 	pagetable_init();
+	bootcmdline_init(cmdline_p);
 	parse_early_param();
 	reserve_initrd_mem();
 

arch/loongarch/kernel/smp.c

@@ -16,6 +16,7 @@
 #include <linux/smp.h>
 #include <linux/threads.h>
 #include <linux/export.h>
+#include <linux/syscore_ops.h>
 #include <linux/time.h>
 #include <linux/tracepoint.h>
 #include <linux/sched/hotplug.h>
@@ -180,8 +181,42 @@ irqreturn_t loongson_ipi_interrupt(int irq, void *dev)
 	return IRQ_HANDLED;
 }
 
+static void __init fdt_smp_setup(void)
+{
+#ifdef CONFIG_OF
+	unsigned int cpu, cpuid;
+	struct device_node *node = NULL;
+
+	for_each_of_cpu_node(node) {
+		if (!of_device_is_available(node))
+			continue;
+
+		cpuid = of_get_cpu_hwid(node, 0);
+		if (cpuid >= nr_cpu_ids)
+			continue;
+
+		if (cpuid == loongson_sysconf.boot_cpu_id) {
+			cpu = 0;
+			numa_add_cpu(cpu);
+		} else {
+			cpu = cpumask_next_zero(-1, cpu_present_mask);
+		}
+
+		num_processors++;
+		set_cpu_possible(cpu, true);
+		set_cpu_present(cpu, true);
+		__cpu_number_map[cpuid] = cpu;
+		__cpu_logical_map[cpu] = cpuid;
+	}
+
+	loongson_sysconf.nr_cpus = num_processors;
+#endif
+}
+
 void __init loongson_smp_setup(void)
 {
+	fdt_smp_setup();
+
 	cpu_data[0].core = cpu_logical_map(0) % loongson_sysconf.cores_per_package;
 	cpu_data[0].package = cpu_logical_map(0) / loongson_sysconf.cores_per_package;
 

arch/loongarch/kernel/switch.S

@@ -23,6 +23,11 @@ SYM_FUNC_START(__switch_to)
 	stptr.d	ra, a0, THREAD_REG01
 	stptr.d a3, a0, THREAD_SCHED_RA
 	stptr.d a4, a0, THREAD_SCHED_CFA
+#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP)
+	la	t7, __stack_chk_guard
+	LONG_L	t8, a1, TASK_STACK_CANARY
+	LONG_S	t8, t7, 0
+#endif
 	move	tp, a2
 	cpu_restore_nonscratch a1
 

arch/loongarch/kernel/time.c

@@ -115,12 +115,17 @@ static unsigned long __init get_loops_per_jiffy(void)
 	return lpj;
 }
 
-static long init_timeval;
+static long init_offset __nosavedata;
+
+void save_counter(void)
+{
+	init_offset = drdtime();
+}
 
 void sync_counter(void)
 {
 	/* Ensure counter begin at 0 */
-	csr_write64(-init_timeval, LOONGARCH_CSR_CNTC);
+	csr_write64(init_offset, LOONGARCH_CSR_CNTC);
 }
 
 static int get_timer_irq(void)
@@ -219,7 +224,7 @@ void __init time_init(void)
 	else
 		const_clock_freq = calc_const_freq();
 
-	init_timeval = drdtime() - csr_read64(LOONGARCH_CSR_CNTC);
+	init_offset = -(drdtime() - csr_read64(LOONGARCH_CSR_CNTC));
 
 	constant_clockevent_init();
 	constant_clocksource_init();

arch/loongarch/kernel/traps.c

@@ -368,13 +368,40 @@ asmlinkage void noinstr do_ade(struct pt_regs *regs)
 	irqentry_exit(regs, state);
 }
 
+/* sysctl hooks */
+int unaligned_enabled __read_mostly = 1;	/* Enabled by default */
+int no_unaligned_warning __read_mostly = 1;	/* Only 1 warning by default */
+
 asmlinkage void noinstr do_ale(struct pt_regs *regs)
 {
+	unsigned int *pc;
 	irqentry_state_t state = irqentry_enter(regs);
 
+	perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, regs->csr_badvaddr);
+
+	/*
+	 * Did we catch a fault trying to load an instruction?
+	 */
+	if (regs->csr_badvaddr == regs->csr_era)
+		goto sigbus;
+	if (user_mode(regs) && !test_thread_flag(TIF_FIXADE))
+		goto sigbus;
+	if (!unaligned_enabled)
+		goto sigbus;
+	if (!no_unaligned_warning)
+		show_registers(regs);
+
+	pc = (unsigned int *)exception_era(regs);
+
+	emulate_load_store_insn(regs, (void __user *)regs->csr_badvaddr, pc);
+
+	goto out;
+
+sigbus:
 	die_if_kernel("Kernel ale access", regs);
 	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)regs->csr_badvaddr);
 
+out:
 	irqentry_exit(regs, state);
 }
 

arch/loongarch/kernel/unaligned.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Handle unaligned accesses by emulation.
+ *
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ *
+ * Derived from MIPS:
+ * Copyright (C) 1996, 1998, 1999, 2002 by Ralf Baechle
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ * Copyright (C) 2014 Imagination Technologies Ltd.
+ */
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/debugfs.h>
+#include <linux/perf_event.h>
+
+#include <asm/asm.h>
+#include <asm/branch.h>
+#include <asm/fpu.h>
+#include <asm/inst.h>
+
+#include "access-helper.h"
+
+#ifdef CONFIG_DEBUG_FS
+static u32 unaligned_instructions_user;
+static u32 unaligned_instructions_kernel;
+#endif
+
+static inline unsigned long read_fpr(unsigned int idx)
+{
+#define READ_FPR(idx, __value)		\
+	__asm__ __volatile__("movfr2gr.d %0, $f"#idx"\n\t" : "=r"(__value));
+
+	unsigned long __value;
+
+	switch (idx) {
+	case 0:
+		READ_FPR(0, __value);
+		break;
+	case 1:
+		READ_FPR(1, __value);
+		break;
+	case 2:
+		READ_FPR(2, __value);
+		break;
+	case 3:
+		READ_FPR(3, __value);
+		break;
+	case 4:
+		READ_FPR(4, __value);
+		break;
+	case 5:
+		READ_FPR(5, __value);
+		break;
+	case 6:
+		READ_FPR(6, __value);
+		break;
+	case 7:
+		READ_FPR(7, __value);
+		break;
+	case 8:
+		READ_FPR(8, __value);
+		break;
+	case 9:
+		READ_FPR(9, __value);
+		break;
+	case 10:
+		READ_FPR(10, __value);
+		break;
+	case 11:
+		READ_FPR(11, __value);
+		break;
+	case 12:
+		READ_FPR(12, __value);
+		break;
+	case 13:
+		READ_FPR(13, __value);
+		break;
+	case 14:
+		READ_FPR(14, __value);
+		break;
+	case 15:
+		READ_FPR(15, __value);
+		break;
+	case 16:
+		READ_FPR(16, __value);
+		break;
+	case 17:
+		READ_FPR(17, __value);
+		break;
+	case 18:
+		READ_FPR(18, __value);
+		break;
+	case 19:
+		READ_FPR(19, __value);
+		break;
+	case 20:
+		READ_FPR(20, __value);
+		break;
+	case 21:
+		READ_FPR(21, __value);
+		break;
+	case 22:
+		READ_FPR(22, __value);
+		break;
+	case 23:
+		READ_FPR(23, __value);
+		break;
+	case 24:
+		READ_FPR(24, __value);
+		break;
+	case 25:
+		READ_FPR(25, __value);
+		break;
+	case 26:
+		READ_FPR(26, __value);
+		break;
+	case 27:
+		READ_FPR(27, __value);
+		break;
+	case 28:
+		READ_FPR(28, __value);
+		break;
+	case 29:
+		READ_FPR(29, __value);
+		break;
+	case 30:
+		READ_FPR(30, __value);
+		break;
+	case 31:
+		READ_FPR(31, __value);
+		break;
+	default:
+		panic("unexpected idx '%d'", idx);
+	}
+#undef READ_FPR
+	return __value;
+}
+
+static inline void write_fpr(unsigned int idx, unsigned long value)
+{
+#define WRITE_FPR(idx, value)		\
+	__asm__ __volatile__("movgr2fr.d $f"#idx", %0\n\t" :: "r"(value));
+
+	switch (idx) {
+	case 0:
+		WRITE_FPR(0, value);
+		break;
+	case 1:
+		WRITE_FPR(1, value);
+		break;
+	case 2:
+		WRITE_FPR(2, value);
+		break;
+	case 3:
+		WRITE_FPR(3, value);
+		break;
+	case 4:
+		WRITE_FPR(4, value);
+		break;
+	case 5:
+		WRITE_FPR(5, value);
+		break;
+	case 6:
+		WRITE_FPR(6, value);
+		break;
+	case 7:
+		WRITE_FPR(7, value);
+		break;
+	case 8:
+		WRITE_FPR(8, value);
+		break;
+	case 9:
+		WRITE_FPR(9, value);
+		break;
+	case 10:
+		WRITE_FPR(10, value);
+		break;
+	case 11:
+		WRITE_FPR(11, value);
+		break;
+	case 12:
+		WRITE_FPR(12, value);
+		break;
+	case 13:
+		WRITE_FPR(13, value);
+		break;
+	case 14:
+		WRITE_FPR(14, value);
+		break;
+	case 15:
+		WRITE_FPR(15, value);
+		break;
+	case 16:
+		WRITE_FPR(16, value);
+		break;
+	case 17:
+		WRITE_FPR(17, value);
+		break;
+	case 18:
+		WRITE_FPR(18, value);
+		break;
+	case 19:
+		WRITE_FPR(19, value);
+		break;
+	case 20:
+		WRITE_FPR(20, value);
+		break;
+	case 21:
+		WRITE_FPR(21, value);
+		break;
+	case 22:
+		WRITE_FPR(22, value);
+		break;
+	case 23:
+		WRITE_FPR(23, value);
+		break;
+	case 24:
+		WRITE_FPR(24, value);
+		break;
+	case 25:
+		WRITE_FPR(25, value);
+		break;
+	case 26:
+		WRITE_FPR(26, value);
+		break;
+	case 27:
+		WRITE_FPR(27, value);
+		break;
+	case 28:
+		WRITE_FPR(28, value);
+		break;
+	case 29:
+		WRITE_FPR(29, value);
+		break;
+	case 30:
+		WRITE_FPR(30, value);
+		break;
+	case 31:
+		WRITE_FPR(31, value);
+		break;
+	default:
+		panic("unexpected idx '%d'", idx);
+	}
+#undef WRITE_FPR
+}
+
+void emulate_load_store_insn(struct pt_regs *regs, void __user *addr, unsigned int *pc)
+{
+	bool fp = false;
+	bool sign, write;
+	bool user = user_mode(regs);
+	unsigned int res, size = 0;
+	unsigned long value = 0;
+	union loongarch_instruction insn;
+
+	perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
+
+	__get_inst(&insn.word, pc, user);
+
+	switch (insn.reg2i12_format.opcode) {
+	case ldh_op:
+		size = 2;
+		sign = true;
+		write = false;
+		break;
+	case ldhu_op:
+		size = 2;
+		sign = false;
+		write = false;
+		break;
+	case sth_op:
+		size = 2;
+		sign = true;
+		write = true;
+		break;
+	case ldw_op:
+		size = 4;
+		sign = true;
+		write = false;
+		break;
+	case ldwu_op:
+		size = 4;
+		sign = false;
+		write = false;
+		break;
+	case stw_op:
+		size = 4;
+		sign = true;
+		write = true;
+		break;
+	case ldd_op:
+		size = 8;
+		sign = true;
+		write = false;
+		break;
+	case std_op:
+		size = 8;
+		sign = true;
+		write = true;
+		break;
+	case flds_op:
+		size = 4;
+		fp = true;
+		sign = true;
+		write = false;
+		break;
+	case fsts_op:
+		size = 4;
+		fp = true;
+		sign = true;
+		write = true;
+		break;
+	case fldd_op:
+		size = 8;
+		fp = true;
+		sign = true;
+		write = false;
+		break;
+	case fstd_op:
+		size = 8;
+		fp = true;
+		sign = true;
+		write = true;
+		break;
+	}
+
+	switch (insn.reg2i14_format.opcode) {
+	case ldptrw_op:
+		size = 4;
+		sign = true;
+		write = false;
+		break;
+	case stptrw_op:
+		size = 4;
+		sign = true;
+		write = true;
+		break;
+	case ldptrd_op:
+		size = 8;
+		sign = true;
+		write = false;
+		break;
+	case stptrd_op:
+		size = 8;
+		sign = true;
+		write = true;
+		break;
+	}
+
+	switch (insn.reg3_format.opcode) {
+	case ldxh_op:
+		size = 2;
+		sign = true;
+		write = false;
+		break;
+	case ldxhu_op:
+		size = 2;
+		sign = false;
+		write = false;
+		break;
+	case stxh_op:
+		size = 2;
+		sign = true;
+		write = true;
+		break;
+	case ldxw_op:
+		size = 4;
+		sign = true;
+		write = false;
+		break;
+	case ldxwu_op:
+		size = 4;
+		sign = false;
+		write = false;
+		break;
+	case stxw_op:
+		size = 4;
+		sign = true;
+		write = true;
+		break;
+	case ldxd_op:
+		size = 8;
+		sign = true;
+		write = false;
+		break;
+	case stxd_op:
+		size = 8;
+		sign = true;
+		write = true;
+		break;
+	case fldxs_op:
+		size = 4;
+		fp = true;
+		sign = true;
+		write = false;
+		break;
+	case fstxs_op:
+		size = 4;
+		fp = true;
+		sign = true;
+		write = true;
+		break;
+	case fldxd_op:
+		size = 8;
+		fp = true;
+		sign = true;
+		write = false;
+		break;
+	case fstxd_op:
+		size = 8;
+		fp = true;
+		sign = true;
+		write = true;
+		break;
+	}
+
+	if (!size)
+		goto sigbus;
+	if (user && !access_ok(addr, size))
+		goto sigbus;
+
+	if (!write) {
+		res = unaligned_read(addr, &value, size, sign);
+		if (res)
+			goto fault;
+
+		/* Rd is the same field in any formats */
+		if (!fp)
+			regs->regs[insn.reg3_format.rd] = value;
+		else {
+			if (is_fpu_owner())
+				write_fpr(insn.reg3_format.rd, value);
+			else
+				set_fpr64(&current->thread.fpu.fpr[insn.reg3_format.rd], 0, value);
+		}
+	} else {
+		/* Rd is the same field in any formats */
+		if (!fp)
+			value = regs->regs[insn.reg3_format.rd];
+		else {
+			if (is_fpu_owner())
+				value = read_fpr(insn.reg3_format.rd);
+			else
+				value = get_fpr64(&current->thread.fpu.fpr[insn.reg3_format.rd], 0);
+		}
+
+		res = unaligned_write(addr, value, size);
+		if (res)
+			goto fault;
+	}
+
+#ifdef CONFIG_DEBUG_FS
+	if (user)
+		unaligned_instructions_user++;
+	else
+		unaligned_instructions_kernel++;
+#endif
+
+	compute_return_era(regs);
+
+	return;
+
+fault:
+	/* Did we have an exception handler installed? */
+	if (fixup_exception(regs))
+		return;
+
+	die_if_kernel("Unhandled kernel unaligned access", regs);
+	force_sig(SIGSEGV);
+
+	return;
+
+sigbus:
+	die_if_kernel("Unhandled kernel unaligned access", regs);
+	force_sig(SIGBUS);
+
+	return;
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int __init debugfs_unaligned(void)
+{
+	struct dentry *d;
+
+	d = debugfs_create_dir("loongarch", NULL);
+	if (!d)
+		return -ENOMEM;
+
+	debugfs_create_u32("unaligned_instructions_user",
+				S_IRUGO, d, &unaligned_instructions_user);
+	debugfs_create_u32("unaligned_instructions_kernel",
+				S_IRUGO, d, &unaligned_instructions_kernel);
+
+	return 0;
+}
+arch_initcall(debugfs_unaligned);
+#endif

arch/loongarch/kernel/unwind_guess.c

@@ -3,6 +3,7 @@
  * Copyright (C) 2022 Loongson Technology Corporation Limited
  */
 #include <linux/kernel.h>
+#include <linux/ftrace.h>
 
 #include <asm/unwind.h>
 
@@ -53,7 +54,8 @@ bool unwind_next_frame(struct unwind_state *state)
 		     state->sp < info->end;
 		     state->sp += sizeof(unsigned long)) {
 			addr = *(unsigned long *)(state->sp);
-
+			state->pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
+					addr, (unsigned long *)(state->sp - GRAPH_FAKE_OFFSET));
 			if (__kernel_text_address(addr))
 				return true;
 		}

arch/loongarch/kernel/unwind_prologue.c

@@ -2,12 +2,23 @@
 /*
  * Copyright (C) 2022 Loongson Technology Corporation Limited
  */
+#include <linux/ftrace.h>
 #include <linux/kallsyms.h>
 
 #include <asm/inst.h>
 #include <asm/ptrace.h>
 #include <asm/unwind.h>
 
+static inline void unwind_state_fixup(struct unwind_state *state)
+{
+#ifdef CONFIG_DYNAMIC_FTRACE
+	static unsigned long ftrace = (unsigned long)ftrace_call + 4;
+
+	if (state->pc == ftrace)
+		state->is_ftrace = true;
+#endif
+}
+
 unsigned long unwind_get_return_address(struct unwind_state *state)
 {
 
@@ -32,6 +43,8 @@ static bool unwind_by_guess(struct unwind_state *state)
 	     state->sp < info->end;
 	     state->sp += sizeof(unsigned long)) {
 		addr = *(unsigned long *)(state->sp);
+		state->pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
+				addr, (unsigned long *)(state->sp - GRAPH_FAKE_OFFSET));
 		if (__kernel_text_address(addr))
 			return true;
 	}
@@ -41,15 +54,30 @@ static bool unwind_by_guess(struct unwind_state *state)
 
 static bool unwind_by_prologue(struct unwind_state *state)
 {
-	struct stack_info *info = &state->stack_info;
-	union loongarch_instruction *ip, *ip_end;
 	long frame_ra = -1;
 	unsigned long frame_size = 0;
 	unsigned long size, offset, pc = state->pc;
+	struct pt_regs *regs;
+	struct stack_info *info = &state->stack_info;
+	union loongarch_instruction *ip, *ip_end;
 
 	if (state->sp >= info->end || state->sp < info->begin)
 		return false;
 
+	if (state->is_ftrace) {
+		/*
+		 * As we meet ftrace_regs_entry, reset first flag like first doing
+		 * tracing. Prologue analysis will stop soon because PC is at entry.
+		 */
+		regs = (struct pt_regs *)state->sp;
+		state->first = true;
+		state->is_ftrace = false;
+		state->pc = regs->csr_era;
+		state->ra = regs->regs[1];
+		state->sp = regs->regs[3];
+		return true;
+	}
+
 	if (!kallsyms_lookup_size_offset(pc, &size, &offset))
 		return false;
 
@@ -95,7 +123,7 @@ static bool unwind_by_prologue(struct unwind_state *state)
 
 	state->pc = *(unsigned long *)(state->sp + frame_ra);
 	state->sp = state->sp + frame_size;
-	return !!__kernel_text_address(state->pc);
+	goto out;
 
 first:
 	state->first = false;
@@ -104,7 +132,9 @@ static bool unwind_by_prologue(struct unwind_state *state)
 
 	state->pc = state->ra;
 
-	return !!__kernel_text_address(state->ra);
+out:
+	unwind_state_fixup(state);
+	return !!__kernel_text_address(state->pc);
 }
 
 void unwind_start(struct unwind_state *state, struct task_struct *task,
@@ -147,8 +177,11 @@ bool unwind_next_frame(struct unwind_state *state)
 			break;
 
 		case UNWINDER_PROLOGUE:
-			if (unwind_by_prologue(state))
+			if (unwind_by_prologue(state)) {
+				state->pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
+						state->pc, (unsigned long *)(state->sp - GRAPH_FAKE_OFFSET));
 				return true;
+			}
 
 			if (info->type == STACK_TYPE_IRQ &&
 				info->end == state->sp) {
@@ -158,10 +191,11 @@ bool unwind_next_frame(struct unwind_state *state)
 				if (user_mode(regs) || !__kernel_text_address(pc))
 					return false;
 
-				state->pc = pc;
-				state->sp = regs->regs[3];
-				state->ra = regs->regs[1];
 				state->first = true;
+				state->ra = regs->regs[1];
+				state->sp = regs->regs[3];
+				state->pc = ftrace_graph_ret_addr(state->task, &state->graph_idx,
+						pc, (unsigned long *)(state->sp - GRAPH_FAKE_OFFSET));
 				get_stack_info(state->sp, state->task, info);
 
 				return true;

arch/loongarch/kernel/vmlinux.lds.S

@@ -4,6 +4,7 @@
 #include <asm/thread_info.h>
 
 #define PAGE_SIZE _PAGE_SIZE
+#define RO_EXCEPTION_TABLE_ALIGN	4
 
 /*
  * Put .bss..swapper_pg_dir as the first thing in .bss. This will
@@ -53,7 +54,17 @@ SECTIONS
 	. = ALIGN(PECOFF_SEGMENT_ALIGN);
 	_etext = .;
 
-	EXCEPTION_TABLE(16)
+	/*
+	 * struct alt_inst entries. From the header (alternative.h):
+	 * "Alternative instructions for different CPU types or capabilities"
+	 * Think locking instructions on spinlocks.
+	 */
+	. = ALIGN(4);
+	.altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {
+		__alt_instructions = .;
+		*(.altinstructions)
+		__alt_instructions_end = .;
+	}
 
 	.got : ALIGN(16) { *(.got) }
 	.plt : ALIGN(16) { *(.plt) }

arch/loongarch/lib/Makefile

@@ -3,4 +3,5 @@
 # Makefile for LoongArch-specific library files.
 #
 
-lib-y	+= delay.o clear_user.o copy_user.o dump_tlb.o
+lib-y	+= delay.o memset.o memcpy.o memmove.o \
+	   clear_user.o copy_user.o dump_tlb.o unaligned.o

arch/loongarch/lib/clear_user.S

@@ -3,30 +3,37 @@
  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
  */
 
+#include <asm/alternative-asm.h>
 #include <asm/asm.h>
 #include <asm/asmmacro.h>
+#include <asm/asm-extable.h>
+#include <asm/cpu.h>
 #include <asm/export.h>
 #include <asm/regdef.h>
 
-.macro fixup_ex from, to, offset, fix
-.if \fix
-	.section .fixup, "ax"
-\to:	addi.d	a0, a1, \offset
+.irp to, 0, 1, 2, 3, 4, 5, 6, 7
+.L_fixup_handle_\to\():
+	addi.d	a0, a1, (\to) * (-8)
 	jr	ra
-	.previous
-.endif
-	.section __ex_table, "a"
-	PTR	\from\()b, \to\()b
-	.previous
-.endm
+.endr
+
+SYM_FUNC_START(__clear_user)
+	/*
+	 * Some CPUs support hardware unaligned access
+	 */
+	ALTERNATIVE	"b __clear_user_generic",	\
+			"b __clear_user_fast", CPU_FEATURE_UAL
+SYM_FUNC_END(__clear_user)
+
+EXPORT_SYMBOL(__clear_user)
 
 /*
- * unsigned long __clear_user(void *addr, size_t size)
+ * unsigned long __clear_user_generic(void *addr, size_t size)
  *
  * a0: addr
  * a1: size
  */
-SYM_FUNC_START(__clear_user)
+SYM_FUNC_START(__clear_user_generic)
 	beqz	a1, 2f
 
 1:	st.b	zero, a0, 0
@@ -37,7 +44,55 @@ SYM_FUNC_START(__clear_user)
 2:	move	a0, a1
 	jr	ra
 
-	fixup_ex 1, 3, 0, 1
-SYM_FUNC_END(__clear_user)
+	_asm_extable 1b, .L_fixup_handle_0
+SYM_FUNC_END(__clear_user_generic)
 
-EXPORT_SYMBOL(__clear_user)
+/*
+ * unsigned long __clear_user_fast(void *addr, unsigned long size)
+ *
+ * a0: addr
+ * a1: size
+ */
+SYM_FUNC_START(__clear_user_fast)
+	beqz	a1, 10f
+
+	ori	a2, zero, 64
+	blt	a1, a2, 9f
+
+	/* set 64 bytes at a time */
+1:	st.d	zero, a0, 0
+2:	st.d	zero, a0, 8
+3:	st.d	zero, a0, 16
+4:	st.d	zero, a0, 24
+5:	st.d	zero, a0, 32
+6:	st.d	zero, a0, 40
+7:	st.d	zero, a0, 48
+8:	st.d	zero, a0, 56
+
+	addi.d	a0, a0, 64
+	addi.d	a1, a1, -64
+	bge	a1, a2, 1b
+
+	beqz	a1, 10f
+
+	/* set the remaining bytes */
+9:	st.b	zero, a0, 0
+	addi.d	a0, a0, 1
+	addi.d	a1, a1, -1
+	bgt	a1, zero, 9b
+
+	/* return */
+10:	move	a0, a1
+	jr	ra
+
+	/* fixup and ex_table */
+	_asm_extable 1b, .L_fixup_handle_0
+	_asm_extable 2b, .L_fixup_handle_1
+	_asm_extable 3b, .L_fixup_handle_2
+	_asm_extable 4b, .L_fixup_handle_3
+	_asm_extable 5b, .L_fixup_handle_4
+	_asm_extable 6b, .L_fixup_handle_5
+	_asm_extable 7b, .L_fixup_handle_6
+	_asm_extable 8b, .L_fixup_handle_7
+	_asm_extable 9b, .L_fixup_handle_0
+SYM_FUNC_END(__clear_user_fast)

arch/loongarch/lib/copy_user.S

@@ -3,31 +3,38 @@
  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
  */
 
+#include <asm/alternative-asm.h>
 #include <asm/asm.h>
 #include <asm/asmmacro.h>
+#include <asm/asm-extable.h>
+#include <asm/cpu.h>
 #include <asm/export.h>
 #include <asm/regdef.h>
 
-.macro fixup_ex from, to, offset, fix
-.if \fix
-	.section .fixup, "ax"
-\to:	addi.d	a0, a2, \offset
+.irp to, 0, 1, 2, 3, 4, 5, 6, 7
+.L_fixup_handle_\to\():
+	addi.d	a0, a2, (\to) * (-8)
 	jr	ra
-	.previous
-.endif
-	.section __ex_table, "a"
-	PTR	\from\()b, \to\()b
-	.previous
-.endm
+.endr
+
+SYM_FUNC_START(__copy_user)
+	/*
+	 * Some CPUs support hardware unaligned access
+	 */
+	ALTERNATIVE	"b __copy_user_generic",	\
+			"b __copy_user_fast", CPU_FEATURE_UAL
+SYM_FUNC_END(__copy_user)
+
+EXPORT_SYMBOL(__copy_user)
 
 /*
- * unsigned long __copy_user(void *to, const void *from, size_t n)
+ * unsigned long __copy_user_generic(void *to, const void *from, size_t n)
  *
  * a0: to
  * a1: from
  * a2: n
  */
-SYM_FUNC_START(__copy_user)
+SYM_FUNC_START(__copy_user_generic)
 	beqz	a2, 3f
 
 1:	ld.b	t0, a1, 0
@@ -40,8 +47,77 @@ SYM_FUNC_START(__copy_user)
 3:	move	a0, a2
 	jr	ra
 
-	fixup_ex 1, 4, 0, 1
-	fixup_ex 2, 4, 0, 0
-SYM_FUNC_END(__copy_user)
+	_asm_extable 1b, .L_fixup_handle_0
+	_asm_extable 2b, .L_fixup_handle_0
+SYM_FUNC_END(__copy_user_generic)
 
-EXPORT_SYMBOL(__copy_user)
+/*
+ * unsigned long __copy_user_fast(void *to, const void *from, unsigned long n)
+ *
+ * a0: to
+ * a1: from
+ * a2: n
+ */
+SYM_FUNC_START(__copy_user_fast)
+	beqz	a2, 19f
+
+	ori	a3, zero, 64
+	blt	a2, a3, 17f
+
+	/* copy 64 bytes at a time */
+1:	ld.d	t0, a1, 0
+2:	ld.d	t1, a1, 8
+3:	ld.d	t2, a1, 16
+4:	ld.d	t3, a1, 24
+5:	ld.d	t4, a1, 32
+6:	ld.d	t5, a1, 40
+7:	ld.d	t6, a1, 48
+8:	ld.d	t7, a1, 56
+9:	st.d	t0, a0, 0
+10:	st.d	t1, a0, 8
+11:	st.d	t2, a0, 16
+12:	st.d	t3, a0, 24
+13:	st.d	t4, a0, 32
+14:	st.d	t5, a0, 40
+15:	st.d	t6, a0, 48
+16:	st.d	t7, a0, 56
+
+	addi.d	a0, a0, 64
+	addi.d	a1, a1, 64
+	addi.d	a2, a2, -64
+	bge	a2, a3, 1b
+
+	beqz	a2, 19f
+
+	/* copy the remaining bytes */
+17:	ld.b	t0, a1, 0
+18:	st.b	t0, a0, 0
+	addi.d	a0, a0, 1
+	addi.d	a1, a1, 1
+	addi.d	a2, a2, -1
+	bgt	a2, zero, 17b
+
+	/* return */
+19:	move	a0, a2
+	jr	ra
+
+	/* fixup and ex_table */
+	_asm_extable 1b, .L_fixup_handle_0
+	_asm_extable 2b, .L_fixup_handle_1
+	_asm_extable 3b, .L_fixup_handle_2
+	_asm_extable 4b, .L_fixup_handle_3
+	_asm_extable 5b, .L_fixup_handle_4
+	_asm_extable 6b, .L_fixup_handle_5
+	_asm_extable 7b, .L_fixup_handle_6
+	_asm_extable 8b, .L_fixup_handle_7
+	_asm_extable 9b, .L_fixup_handle_0
+	_asm_extable 10b, .L_fixup_handle_1
+	_asm_extable 11b, .L_fixup_handle_2
+	_asm_extable 12b, .L_fixup_handle_3
+	_asm_extable 13b, .L_fixup_handle_4
+	_asm_extable 14b, .L_fixup_handle_5
+	_asm_extable 15b, .L_fixup_handle_6
+	_asm_extable 16b, .L_fixup_handle_7
+	_asm_extable 17b, .L_fixup_handle_0
+	_asm_extable 18b, .L_fixup_handle_0
+SYM_FUNC_END(__copy_user_fast)

arch/loongarch/lib/memcpy.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/alternative-asm.h>
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/cpu.h>
+#include <asm/export.h>
+#include <asm/regdef.h>
+
+SYM_FUNC_START(memcpy)
+	/*
+	 * Some CPUs support hardware unaligned access
+	 */
+	ALTERNATIVE	"b __memcpy_generic", \
+			"b __memcpy_fast", CPU_FEATURE_UAL
+SYM_FUNC_END(memcpy)
+
+EXPORT_SYMBOL(memcpy)
+
+/*
+ * void *__memcpy_generic(void *dst, const void *src, size_t n)
+ *
+ * a0: dst
+ * a1: src
+ * a2: n
+ */
+SYM_FUNC_START(__memcpy_generic)
+	move	a3, a0
+	beqz	a2, 2f
+
+1:	ld.b	t0, a1, 0
+	st.b	t0, a0, 0
+	addi.d	a0, a0, 1
+	addi.d	a1, a1, 1
+	addi.d	a2, a2, -1
+	bgt	a2, zero, 1b
+
+2:	move	a0, a3
+	jr	ra
+SYM_FUNC_END(__memcpy_generic)
+
+/*
+ * void *__memcpy_fast(void *dst, const void *src, size_t n)
+ *
+ * a0: dst
+ * a1: src
+ * a2: n
+ */
+SYM_FUNC_START(__memcpy_fast)
+	move	a3, a0
+	beqz	a2, 3f
+
+	ori	a4, zero, 64
+	blt	a2, a4, 2f
+
+	/* copy 64 bytes at a time */
+1:	ld.d	t0, a1, 0
+	ld.d	t1, a1, 8
+	ld.d	t2, a1, 16
+	ld.d	t3, a1, 24
+	ld.d	t4, a1, 32
+	ld.d	t5, a1, 40
+	ld.d	t6, a1, 48
+	ld.d	t7, a1, 56
+	st.d	t0, a0, 0
+	st.d	t1, a0, 8
+	st.d	t2, a0, 16
+	st.d	t3, a0, 24
+	st.d	t4, a0, 32
+	st.d	t5, a0, 40
+	st.d	t6, a0, 48
+	st.d	t7, a0, 56
+
+	addi.d	a0, a0, 64
+	addi.d	a1, a1, 64
+	addi.d	a2, a2, -64
+	bge	a2, a4, 1b
+
+	beqz	a2, 3f
+
+	/* copy the remaining bytes */
+2:	ld.b	t0, a1, 0
+	st.b	t0, a0, 0
+	addi.d	a0, a0, 1
+	addi.d	a1, a1, 1
+	addi.d	a2, a2, -1
+	bgt	a2, zero, 2b
+
+	/* return */
+3:	move	a0, a3
+	jr	ra
+SYM_FUNC_END(__memcpy_fast)

arch/loongarch/lib/memmove.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/alternative-asm.h>
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/cpu.h>
+#include <asm/export.h>
+#include <asm/regdef.h>
+
+SYM_FUNC_START(memmove)
+	blt	a0, a1, 1f	/* dst < src, memcpy */
+	blt	a1, a0, 3f	/* src < dst, rmemcpy */
+	jr	ra		/* dst == src, return */
+
+	/* if (src - dst) < 64, copy 1 byte at a time */
+1:	ori	a3, zero, 64
+	sub.d	t0, a1, a0
+	blt	t0, a3, 2f
+	b	memcpy
+2:	b	__memcpy_generic
+
+	/* if (dst - src) < 64, copy 1 byte at a time */
+3:	ori	a3, zero, 64
+	sub.d	t0, a0, a1
+	blt	t0, a3, 4f
+	b	rmemcpy
+4:	b	__rmemcpy_generic
+SYM_FUNC_END(memmove)
+
+EXPORT_SYMBOL(memmove)
+
+SYM_FUNC_START(rmemcpy)
+	/*
+	 * Some CPUs support hardware unaligned access
+	 */
+	ALTERNATIVE	"b __rmemcpy_generic", \
+			"b __rmemcpy_fast", CPU_FEATURE_UAL
+SYM_FUNC_END(rmemcpy)
+
+/*
+ * void *__rmemcpy_generic(void *dst, const void *src, size_t n)
+ *
+ * a0: dst
+ * a1: src
+ * a2: n
+ */
+SYM_FUNC_START(__rmemcpy_generic)
+	move	a3, a0
+	beqz	a2, 2f
+
+	add.d	a0, a0, a2
+	add.d	a1, a1, a2
+
+1:	ld.b	t0, a1, -1
+	st.b	t0, a0, -1
+	addi.d	a0, a0, -1
+	addi.d	a1, a1, -1
+	addi.d	a2, a2, -1
+	bgt	a2, zero, 1b
+
+2:	move	a0, a3
+	jr	ra
+SYM_FUNC_END(__rmemcpy_generic)
+
+/*
+ * void *__rmemcpy_fast(void *dst, const void *src, size_t n)
+ *
+ * a0: dst
+ * a1: src
+ * a2: n
+ */
+SYM_FUNC_START(__rmemcpy_fast)
+	move	a3, a0
+	beqz	a2, 3f
+
+	add.d	a0, a0, a2
+	add.d	a1, a1, a2
+
+	ori	a4, zero, 64
+	blt	a2, a4, 2f
+
+	/* copy 64 bytes at a time */
+1:	ld.d	t0, a1, -8
+	ld.d	t1, a1, -16
+	ld.d	t2, a1, -24
+	ld.d	t3, a1, -32
+	ld.d	t4, a1, -40
+	ld.d	t5, a1, -48
+	ld.d	t6, a1, -56
+	ld.d	t7, a1, -64
+	st.d	t0, a0, -8
+	st.d	t1, a0, -16
+	st.d	t2, a0, -24
+	st.d	t3, a0, -32
+	st.d	t4, a0, -40
+	st.d	t5, a0, -48
+	st.d	t6, a0, -56
+	st.d	t7, a0, -64
+
+	addi.d	a0, a0, -64
+	addi.d	a1, a1, -64
+	addi.d	a2, a2, -64
+	bge	a2, a4, 1b
+
+	beqz	a2, 3f
+
+	/* copy the remaining bytes */
+2:	ld.b	t0, a1, -1
+	st.b	t0, a0, -1
+	addi.d	a0, a0, -1
+	addi.d	a1, a1, -1
+	addi.d	a2, a2, -1
+	bgt	a2, zero, 2b
+
+	/* return */
+3:	move	a0, a3
+	jr	ra
+SYM_FUNC_END(__rmemcpy_fast)

arch/loongarch/lib/memset.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/alternative-asm.h>
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/cpu.h>
+#include <asm/export.h>
+#include <asm/regdef.h>
+
+.macro fill_to_64 r0
+	bstrins.d \r0, \r0, 15, 8
+	bstrins.d \r0, \r0, 31, 16
+	bstrins.d \r0, \r0, 63, 32
+.endm
+
+SYM_FUNC_START(memset)
+	/*
+	 * Some CPUs support hardware unaligned access
+	 */
+	ALTERNATIVE	"b __memset_generic", \
+			"b __memset_fast", CPU_FEATURE_UAL
+SYM_FUNC_END(memset)
+
+EXPORT_SYMBOL(memset)
+
+/*
+ * void *__memset_generic(void *s, int c, size_t n)
+ *
+ * a0: s
+ * a1: c
+ * a2: n
+ */
+SYM_FUNC_START(__memset_generic)
+	move	a3, a0
+	beqz	a2, 2f
+
+1:	st.b	a1, a0, 0
+	addi.d	a0, a0, 1
+	addi.d	a2, a2, -1
+	bgt	a2, zero, 1b
+
+2:	move	a0, a3
+	jr	ra
+SYM_FUNC_END(__memset_generic)
+
+/*
+ * void *__memset_fast(void *s, int c, size_t n)
+ *
+ * a0: s
+ * a1: c
+ * a2: n
+ */
+SYM_FUNC_START(__memset_fast)
+	move	a3, a0
+	beqz	a2, 3f
+
+	ori	a4, zero, 64
+	blt	a2, a4, 2f
+
+	/* fill a1 to 64 bits */
+	fill_to_64 a1
+
+	/* set 64 bytes at a time */
+1:	st.d	a1, a0, 0
+	st.d	a1, a0, 8
+	st.d	a1, a0, 16
+	st.d	a1, a0, 24
+	st.d	a1, a0, 32
+	st.d	a1, a0, 40
+	st.d	a1, a0, 48
+	st.d	a1, a0, 56
+
+	addi.d	a0, a0, 64
+	addi.d	a2, a2, -64
+	bge	a2, a4, 1b
+
+	beqz	a2, 3f
+
+	/* set the remaining bytes */
+2:	st.b	a1, a0, 0
+	addi.d	a0, a0, 1
+	addi.d	a2, a2, -1
+	bgt	a2, zero, 2b
+
+	/* return */
+3:	move	a0, a3
+	jr	ra
+SYM_FUNC_END(__memset_fast)

arch/loongarch/lib/unaligned.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/asm-extable.h>
+#include <asm/errno.h>
+#include <asm/export.h>
+#include <asm/regdef.h>
+
+.L_fixup_handle_unaligned:
+	li.w	a0, -EFAULT
+	jr	ra
+
+/*
+ * unsigned long unaligned_read(void *addr, void *value, unsigned long n, bool sign)
+ *
+ * a0: addr
+ * a1: value
+ * a2: n
+ * a3: sign
+ */
+SYM_FUNC_START(unaligned_read)
+	beqz	a2, 5f
+
+	li.w	t2, 0
+	addi.d	t0, a2, -1
+	slli.d	t1, t0, 3
+	add.d 	a0, a0, t0
+
+	beqz	a3, 2f
+1:	ld.b	t3, a0, 0
+	b	3f
+
+2:	ld.bu	t3, a0, 0
+3:	sll.d	t3, t3, t1
+	or	t2, t2, t3
+	addi.d	t1, t1, -8
+	addi.d	a0, a0, -1
+	addi.d	a2, a2, -1
+	bgtz	a2, 2b
+4:	st.d	t2, a1, 0
+
+	move	a0, a2
+	jr	ra
+
+5:	li.w    a0, -EFAULT
+	jr	ra
+
+	_asm_extable 1b, .L_fixup_handle_unaligned
+	_asm_extable 2b, .L_fixup_handle_unaligned
+	_asm_extable 4b, .L_fixup_handle_unaligned
+SYM_FUNC_END(unaligned_read)
+
+/*
+ * unsigned long unaligned_write(void *addr, unsigned long value, unsigned long n)
+ *
+ * a0: addr
+ * a1: value
+ * a2: n
+ */
+SYM_FUNC_START(unaligned_write)
+	beqz	a2, 3f
+
+	li.w	t0, 0
+1:	srl.d	t1, a1, t0
+2:	st.b	t1, a0, 0
+	addi.d	t0, t0, 8
+	addi.d	a2, a2, -1
+	addi.d	a0, a0, 1
+	bgtz	a2, 1b
+
+	move	a0, a2
+	jr	ra
+
+3:	li.w    a0, -EFAULT
+	jr	ra
+
+	_asm_extable 2b, .L_fixup_handle_unaligned
+SYM_FUNC_END(unaligned_write)

arch/loongarch/mm/extable.c

@@ -2,21 +2,62 @@
 /*
  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
  */
+#include <linux/bitfield.h>
 #include <linux/extable.h>
-#include <linux/spinlock.h>
-#include <asm/branch.h>
 #include <linux/uaccess.h>
+#include <asm/asm-extable.h>
+#include <asm/branch.h>
+
+static inline unsigned long
+get_ex_fixup(const struct exception_table_entry *ex)
+{
+	return ((unsigned long)&ex->fixup + ex->fixup);
+}
+
+static inline void regs_set_gpr(struct pt_regs *regs,
+				unsigned int offset, unsigned long val)
+{
+	if (offset && offset <= MAX_REG_OFFSET)
+		*(unsigned long *)((unsigned long)regs + offset) = val;
+}
+
+static bool ex_handler_fixup(const struct exception_table_entry *ex,
+			     struct pt_regs *regs)
+{
+	regs->csr_era = get_ex_fixup(ex);
+
+	return true;
+}
+
+static bool ex_handler_uaccess_err_zero(const struct exception_table_entry *ex,
+					struct pt_regs *regs)
+{
+	int reg_err = FIELD_GET(EX_DATA_REG_ERR, ex->data);
+	int reg_zero = FIELD_GET(EX_DATA_REG_ZERO, ex->data);
+
+	regs_set_gpr(regs, reg_err * sizeof(unsigned long), -EFAULT);
+	regs_set_gpr(regs, reg_zero * sizeof(unsigned long), 0);
+	regs->csr_era = get_ex_fixup(ex);
+
+	return true;
+}
 
-int fixup_exception(struct pt_regs *regs)
+bool fixup_exception(struct pt_regs *regs)
 {
-	const struct exception_table_entry *fixup;
+	const struct exception_table_entry *ex;
 
-	fixup = search_exception_tables(exception_era(regs));
-	if (fixup) {
-		regs->csr_era = fixup->fixup;
+	ex = search_exception_tables(exception_era(regs));
+	if (!ex)
+		return false;
 
-		return 1;
+	switch (ex->type) {
+	case EX_TYPE_FIXUP:
+		return ex_handler_fixup(ex, regs);
+	case EX_TYPE_UACCESS_ERR_ZERO:
+		return ex_handler_uaccess_err_zero(ex, regs);
+	case EX_TYPE_BPF:
+		return ex_handler_bpf(ex, regs);
 	}
 
-	return 0;
+	BUG();
 }

arch/loongarch/net/bpf_jit.c

@@ -387,6 +387,65 @@ static bool is_signed_bpf_cond(u8 cond)
 	       cond == BPF_JSGE || cond == BPF_JSLE;
 }
 
+#define BPF_FIXUP_REG_MASK	GENMASK(31, 27)
+#define BPF_FIXUP_OFFSET_MASK	GENMASK(26, 0)
+
+bool ex_handler_bpf(const struct exception_table_entry *ex,
+		    struct pt_regs *regs)
+{
+	int dst_reg = FIELD_GET(BPF_FIXUP_REG_MASK, ex->fixup);
+	off_t offset = FIELD_GET(BPF_FIXUP_OFFSET_MASK, ex->fixup);
+
+	regs->regs[dst_reg] = 0;
+	regs->csr_era = (unsigned long)&ex->fixup - offset;
+
+	return true;
+}
+
+/* For accesses to BTF pointers, add an entry to the exception table */
+static int add_exception_handler(const struct bpf_insn *insn,
+				 struct jit_ctx *ctx,
+				 int dst_reg)
+{
+	unsigned long pc;
+	off_t offset;
+	struct exception_table_entry *ex;
+
+	if (!ctx->image || !ctx->prog->aux->extable || BPF_MODE(insn->code) != BPF_PROBE_MEM)
+		return 0;
+
+	if (WARN_ON_ONCE(ctx->num_exentries >= ctx->prog->aux->num_exentries))
+		return -EINVAL;
+
+	ex = &ctx->prog->aux->extable[ctx->num_exentries];
+	pc = (unsigned long)&ctx->image[ctx->idx - 1];
+
+	offset = pc - (long)&ex->insn;
+	if (WARN_ON_ONCE(offset >= 0 || offset < INT_MIN))
+		return -ERANGE;
+
+	ex->insn = offset;
+
+	/*
+	 * Since the extable follows the program, the fixup offset is always
+	 * negative and limited to BPF_JIT_REGION_SIZE. Store a positive value
+	 * to keep things simple, and put the destination register in the upper
+	 * bits. We don't need to worry about buildtime or runtime sort
+	 * modifying the upper bits because the table is already sorted, and
+	 * isn't part of the main exception table.
+	 */
+	offset = (long)&ex->fixup - (pc + LOONGARCH_INSN_SIZE);
+	if (!FIELD_FIT(BPF_FIXUP_OFFSET_MASK, offset))
+		return -ERANGE;
+
+	ex->type = EX_TYPE_BPF;
+	ex->fixup = FIELD_PREP(BPF_FIXUP_OFFSET_MASK, offset) | FIELD_PREP(BPF_FIXUP_REG_MASK, dst_reg);
+
+	ctx->num_exentries++;
+
+	return 0;
+}
+
 static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool extra_pass)
 {
 	u8 tm = -1;
@@ -816,6 +875,10 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext
 	case BPF_LDX | BPF_MEM | BPF_H:
 	case BPF_LDX | BPF_MEM | BPF_W:
 	case BPF_LDX | BPF_MEM | BPF_DW:
+	case BPF_LDX | BPF_PROBE_MEM | BPF_DW:
+	case BPF_LDX | BPF_PROBE_MEM | BPF_W:
+	case BPF_LDX | BPF_PROBE_MEM | BPF_H:
+	case BPF_LDX | BPF_PROBE_MEM | BPF_B:
 		switch (BPF_SIZE(code)) {
 		case BPF_B:
 			if (is_signed_imm12(off)) {
@@ -854,6 +917,10 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext
 			}
 			break;
 		}
+
+		ret = add_exception_handler(insn, ctx, dst);
+		if (ret)
+			return ret;
 		break;
 
 	/* *(size *)(dst + off) = imm */
@@ -1018,6 +1085,9 @@ static int validate_code(struct jit_ctx *ctx)
 			return -1;
 	}
 
+	if (WARN_ON_ONCE(ctx->num_exentries != ctx->prog->aux->num_exentries))
+		return -1;
+
 	return 0;
 }
 
@@ -1025,7 +1095,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 {
 	bool tmp_blinded = false, extra_pass = false;
 	u8 *image_ptr;
-	int image_size;
+	int image_size, prog_size, extable_size;
 	struct jit_ctx ctx;
 	struct jit_data *jit_data;
 	struct bpf_binary_header *header;
@@ -1066,7 +1136,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 		image_ptr = jit_data->image;
 		header = jit_data->header;
 		extra_pass = true;
-		image_size = sizeof(u32) * ctx.idx;
+		prog_size = sizeof(u32) * ctx.idx;
 		goto skip_init_ctx;
 	}
 
@@ -1088,12 +1158,15 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 	ctx.epilogue_offset = ctx.idx;
 	build_epilogue(&ctx);
 
+	extable_size = prog->aux->num_exentries * sizeof(struct exception_table_entry);
+
 	/* Now we know the actual image size.
 	 * As each LoongArch instruction is of length 32bit,
 	 * we are translating number of JITed intructions into
 	 * the size required to store these JITed code.
 	 */
-	image_size = sizeof(u32) * ctx.idx;
+	prog_size = sizeof(u32) * ctx.idx;
+	image_size = prog_size + extable_size;
 	/* Now we know the size of the structure to make */
 	header = bpf_jit_binary_alloc(image_size, &image_ptr,
 				      sizeof(u32), jit_fill_hole);
@@ -1104,9 +1177,12 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 
 	/* 2. Now, the actual pass to generate final JIT code */
 	ctx.image = (union loongarch_instruction *)image_ptr;
+	if (extable_size)
+		prog->aux->extable = (void *)image_ptr + prog_size;
 
 skip_init_ctx:
 	ctx.idx = 0;
+	ctx.num_exentries = 0;
 
 	build_prologue(&ctx);
 	if (build_body(&ctx, extra_pass)) {
@@ -1125,7 +1201,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 
 	/* And we're done */
 	if (bpf_jit_enable > 1)
-		bpf_jit_dump(prog->len, image_size, 2, ctx.image);
+		bpf_jit_dump(prog->len, prog_size, 2, ctx.image);
 
 	/* Update the icache */
 	flush_icache_range((unsigned long)header, (unsigned long)(ctx.image + ctx.idx));
@@ -1147,7 +1223,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 		jit_data->header = header;
 	}
 	prog->jited = 1;
-	prog->jited_len = image_size;
+	prog->jited_len = prog_size;
 	prog->bpf_func = (void *)ctx.image;
 
 	if (!prog->is_func || extra_pass) {

arch/loongarch/net/bpf_jit.h

@@ -4,6 +4,7 @@
  *
  * Copyright (C) 2022 Loongson Technology Corporation Limited
  */
+#include <linux/bitfield.h>
 #include <linux/bpf.h>
 #include <linux/filter.h>
 #include <asm/cacheflush.h>
@@ -15,6 +16,7 @@ struct jit_ctx {
 	unsigned int flags;
 	unsigned int epilogue_offset;
 	u32 *offset;
+	int num_exentries;
 	union loongarch_instruction *image;
 	u32 stack_size;
 };

arch/loongarch/pci/acpi.c

@@ -26,9 +26,12 @@ void pcibios_add_bus(struct pci_bus *bus)
 
 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
 {
-	struct pci_config_window *cfg = bridge->bus->sysdata;
-	struct acpi_device *adev = to_acpi_device(cfg->parent);
+	struct acpi_device *adev = NULL;
 	struct device *bus_dev = &bridge->bus->dev;
+	struct pci_config_window *cfg = bridge->bus->sysdata;
+
+	if (!acpi_disabled)
+		adev = to_acpi_device(cfg->parent);
 
 	ACPI_COMPANION_SET(&bridge->dev, adev);
 	set_dev_node(bus_dev, pa_to_nid(cfg->res.start));

arch/loongarch/power/Makefile

+obj-y	+= platform.o
+
+obj-$(CONFIG_SUSPEND)		+= suspend.o suspend_asm.o
+obj-$(CONFIG_HIBERNATION)	+= hibernate.o hibernate_asm.o

arch/loongarch/power/hibernate.c

+// SPDX-License-Identifier: GPL-2.0
+#include <asm/fpu.h>
+#include <asm/loongson.h>
+#include <asm/sections.h>
+#include <asm/tlbflush.h>
+#include <linux/suspend.h>
+
+static u32 saved_crmd;
+static u32 saved_prmd;
+static u32 saved_euen;
+static u32 saved_ecfg;
+static u64 saved_pcpu_base;
+struct pt_regs saved_regs;
+
+void save_processor_state(void)
+{
+	saved_crmd = csr_read32(LOONGARCH_CSR_CRMD);
+	saved_prmd = csr_read32(LOONGARCH_CSR_PRMD);
+	saved_euen = csr_read32(LOONGARCH_CSR_EUEN);
+	saved_ecfg = csr_read32(LOONGARCH_CSR_ECFG);
+	saved_pcpu_base = csr_read64(PERCPU_BASE_KS);
+
+	if (is_fpu_owner())
+		save_fp(current);
+}
+
+void restore_processor_state(void)
+{
+	csr_write32(saved_crmd, LOONGARCH_CSR_CRMD);
+	csr_write32(saved_prmd, LOONGARCH_CSR_PRMD);
+	csr_write32(saved_euen, LOONGARCH_CSR_EUEN);
+	csr_write32(saved_ecfg, LOONGARCH_CSR_ECFG);
+	csr_write64(saved_pcpu_base, PERCPU_BASE_KS);
+
+	if (is_fpu_owner())
+		restore_fp(current);
+}
+
+int pfn_is_nosave(unsigned long pfn)
+{
+	unsigned long nosave_begin_pfn = PFN_DOWN(__pa(&__nosave_begin));
+	unsigned long nosave_end_pfn = PFN_UP(__pa(&__nosave_end));
+
+	return	(pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
+}
+
+extern int swsusp_asm_suspend(void);
+
+int swsusp_arch_suspend(void)
+{
+	enable_pci_wakeup();
+	return swsusp_asm_suspend();
+}
+
+extern int swsusp_asm_resume(void);
+
+int swsusp_arch_resume(void)
+{
+	/* Avoid TLB mismatch during and after kernel resume */
+	local_flush_tlb_all();
+	return swsusp_asm_resume();
+}

arch/loongarch/power/hibernate_asm.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Hibernation support specific for LoongArch
+ *
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#include <linux/linkage.h>
+#include <asm/asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/regdef.h>
+
+.text
+SYM_FUNC_START(swsusp_asm_suspend)
+	la.pcrel	t0, saved_regs
+	PTR_S		ra, t0, PT_R1
+	PTR_S		tp, t0, PT_R2
+	PTR_S		sp, t0, PT_R3
+	PTR_S		u0, t0, PT_R21
+	PTR_S		fp, t0, PT_R22
+	PTR_S		s0, t0, PT_R23
+	PTR_S		s1, t0, PT_R24
+	PTR_S		s2, t0, PT_R25
+	PTR_S		s3, t0, PT_R26
+	PTR_S		s4, t0, PT_R27
+	PTR_S		s5, t0, PT_R28
+	PTR_S		s6, t0, PT_R29
+	PTR_S		s7, t0, PT_R30
+	PTR_S		s8, t0, PT_R31
+	b		swsusp_save
+SYM_FUNC_END(swsusp_asm_suspend)
+
+SYM_FUNC_START(swsusp_asm_resume)
+	la.pcrel	t0, restore_pblist
+	PTR_L		t0, t0, 0
+0:
+	PTR_L		t1, t0, PBE_ADDRESS  /* source */
+	PTR_L		t2, t0, PBE_ORIG_ADDRESS /* destination */
+	PTR_LI		t3, _PAGE_SIZE
+	PTR_ADD		t3, t3, t1
+1:
+	REG_L		t8, t1, 0
+	REG_S		t8, t2, 0
+	PTR_ADDI	t1, t1, SZREG
+	PTR_ADDI	t2, t2, SZREG
+	bne		t1, t3, 1b
+	PTR_L		t0, t0, PBE_NEXT
+	bnez		t0, 0b
+	la.pcrel	t0, saved_regs
+	PTR_L		ra, t0, PT_R1
+	PTR_L		tp, t0, PT_R2
+	PTR_L		sp, t0, PT_R3
+	PTR_L		u0, t0, PT_R21
+	PTR_L		fp, t0, PT_R22
+	PTR_L		s0, t0, PT_R23
+	PTR_L		s1, t0, PT_R24
+	PTR_L		s2, t0, PT_R25
+	PTR_L		s3, t0, PT_R26
+	PTR_L		s4, t0, PT_R27
+	PTR_L		s5, t0, PT_R28
+	PTR_L		s6, t0, PT_R29
+	PTR_L		s7, t0, PT_R30
+	PTR_L		s8, t0, PT_R31
+	PTR_LI		a0, 0x0
+	jirl		zero, ra, 0
+SYM_FUNC_END(swsusp_asm_resume)

arch/loongarch/power/platform.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#include <linux/acpi.h>
+#include <linux/platform_device.h>
+
+#include <asm/bootinfo.h>
+#include <asm/loongson.h>
+
+void enable_gpe_wakeup(void)
+{
+	if (acpi_disabled)
+	       return;
+
+	if (acpi_gbl_reduced_hardware)
+	       return;
+
+	acpi_enable_all_wakeup_gpes();
+}
+
+void enable_pci_wakeup(void)
+{
+	if (acpi_disabled)
+	       return;
+
+	if (acpi_gbl_reduced_hardware)
+	       return;
+
+	acpi_write_bit_register(ACPI_BITREG_PCIEXP_WAKE_STATUS, 1);
+
+	if (acpi_gbl_FADT.flags & ACPI_FADT_PCI_EXPRESS_WAKE)
+		acpi_write_bit_register(ACPI_BITREG_PCIEXP_WAKE_DISABLE, 0);
+}
+
+static int __init loongson3_acpi_suspend_init(void)
+{
+#ifdef CONFIG_ACPI
+	acpi_status status;
+	uint64_t suspend_addr = 0;
+
+	if (acpi_disabled || acpi_gbl_reduced_hardware)
+		return 0;
+
+	acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
+	status = acpi_evaluate_integer(NULL, "\\SADR", NULL, &suspend_addr);
+	if (ACPI_FAILURE(status) || !suspend_addr) {
+		pr_err("ACPI S3 is not support!\n");
+		return -1;
+	}
+	loongson_sysconf.suspend_addr = (u64)phys_to_virt(PHYSADDR(suspend_addr));
+#endif
+	return 0;
+}
+
+device_initcall(loongson3_acpi_suspend_init);

arch/loongarch/power/suspend.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * loongson-specific suspend support
+ *
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#include <linux/acpi.h>
+#include <linux/pm.h>
+#include <linux/suspend.h>
+
+#include <asm/loongarch.h>
+#include <asm/loongson.h>
+#include <asm/setup.h>
+#include <asm/time.h>
+#include <asm/tlbflush.h>
+
+u64 loongarch_suspend_addr;
+
+struct saved_registers {
+	u32 ecfg;
+	u32 euen;
+	u64 pgd;
+	u64 kpgd;
+	u32 pwctl0;
+	u32 pwctl1;
+};
+static struct saved_registers saved_regs;
+
+static void arch_common_suspend(void)
+{
+	save_counter();
+	saved_regs.pgd = csr_read64(LOONGARCH_CSR_PGDL);
+	saved_regs.kpgd = csr_read64(LOONGARCH_CSR_PGDH);
+	saved_regs.pwctl0 = csr_read32(LOONGARCH_CSR_PWCTL0);
+	saved_regs.pwctl1 = csr_read32(LOONGARCH_CSR_PWCTL1);
+	saved_regs.ecfg = csr_read32(LOONGARCH_CSR_ECFG);
+	saved_regs.euen = csr_read32(LOONGARCH_CSR_EUEN);
+
+	loongarch_suspend_addr = loongson_sysconf.suspend_addr;
+}
+
+static void arch_common_resume(void)
+{
+	sync_counter();
+	local_flush_tlb_all();
+	csr_write64(per_cpu_offset(0), PERCPU_BASE_KS);
+	csr_write64(eentry, LOONGARCH_CSR_EENTRY);
+	csr_write64(eentry, LOONGARCH_CSR_MERRENTRY);
+	csr_write64(tlbrentry, LOONGARCH_CSR_TLBRENTRY);
+
+	csr_write64(saved_regs.pgd, LOONGARCH_CSR_PGDL);
+	csr_write64(saved_regs.kpgd, LOONGARCH_CSR_PGDH);
+	csr_write32(saved_regs.pwctl0, LOONGARCH_CSR_PWCTL0);
+	csr_write32(saved_regs.pwctl1, LOONGARCH_CSR_PWCTL1);
+	csr_write32(saved_regs.ecfg, LOONGARCH_CSR_ECFG);
+	csr_write32(saved_regs.euen, LOONGARCH_CSR_EUEN);
+}
+
+int loongarch_acpi_suspend(void)
+{
+	enable_gpe_wakeup();
+	enable_pci_wakeup();
+
+	arch_common_suspend();
+
+	/* processor specific suspend */
+	loongarch_suspend_enter();
+
+	arch_common_resume();
+
+	return 0;
+}

arch/loongarch/power/suspend_asm.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Sleep helper for Loongson-3 sleep mode.
+ *
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/addrspace.h>
+#include <asm/loongarch.h>
+#include <asm/stackframe.h>
+
+/* preparatory stuff */
+.macro	SETUP_SLEEP
+	addi.d		sp, sp, -PT_SIZE
+	st.d		$r1, sp, PT_R1
+	st.d		$r2, sp, PT_R2
+	st.d		$r3, sp, PT_R3
+	st.d		$r4, sp, PT_R4
+	st.d		$r21, sp, PT_R21
+	st.d		$r22, sp, PT_R22
+	st.d		$r23, sp, PT_R23
+	st.d		$r24, sp, PT_R24
+	st.d		$r25, sp, PT_R25
+	st.d		$r26, sp, PT_R26
+	st.d		$r27, sp, PT_R27
+	st.d		$r28, sp, PT_R28
+	st.d		$r29, sp, PT_R29
+	st.d		$r30, sp, PT_R30
+	st.d		$r31, sp, PT_R31
+
+	la.pcrel	t0, acpi_saved_sp
+	st.d		sp, t0, 0
+.endm
+
+.macro SETUP_WAKEUP
+	ld.d		$r1, sp, PT_R1
+	ld.d		$r2, sp, PT_R2
+	ld.d		$r3, sp, PT_R3
+	ld.d		$r4, sp, PT_R4
+	ld.d		$r21, sp, PT_R21
+	ld.d		$r22, sp, PT_R22
+	ld.d		$r23, sp, PT_R23
+	ld.d		$r24, sp, PT_R24
+	ld.d		$r25, sp, PT_R25
+	ld.d		$r26, sp, PT_R26
+	ld.d		$r27, sp, PT_R27
+	ld.d		$r28, sp, PT_R28
+	ld.d		$r29, sp, PT_R29
+	ld.d		$r30, sp, PT_R30
+	ld.d		$r31, sp, PT_R31
+.endm
+
+	.text
+	.align 12
+
+/* Sleep/wakeup code for Loongson-3 */
+SYM_FUNC_START(loongarch_suspend_enter)
+	SETUP_SLEEP
+	bl		__flush_cache_all
+
+	/* Pass RA and SP to BIOS */
+	addi.d		a1, sp, 0
+	la.pcrel	a0, loongarch_wakeup_start
+	la.pcrel	t0, loongarch_suspend_addr
+	ld.d		t0, t0, 0
+	jirl		a0, t0, 0 /* Call BIOS's STR sleep routine */
+
+	/*
+	 * This is where we return upon wakeup.
+	 * Reload all of the registers and return.
+	 */
+SYM_INNER_LABEL(loongarch_wakeup_start, SYM_L_GLOBAL)
+	li.d		t0, CSR_DMW0_INIT	# UC, PLV0
+	csrwr		t0, LOONGARCH_CSR_DMWIN0
+	li.d		t0, CSR_DMW1_INIT	# CA, PLV0
+	csrwr		t0, LOONGARCH_CSR_DMWIN1
+
+	la.abs		t0, 0f
+	jr		t0
+0:
+	la.pcrel	t0, acpi_saved_sp
+	ld.d		sp, t0, 0
+	SETUP_WAKEUP
+	addi.d		sp, sp, PT_SIZE
+	jr		ra
+SYM_FUNC_END(loongarch_suspend_enter)

scripts/mod/modpost.c

@@ -1523,6 +1523,14 @@ static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
 #define R_RISCV_SUB32		39
 #endif
 
+#ifndef EM_LOONGARCH
+#define EM_LOONGARCH		258
+#endif
+
+#ifndef R_LARCH_SUB32
+#define R_LARCH_SUB32		55
+#endif
+
 static void section_rela(const char *modname, struct elf_info *elf,
 			 Elf_Shdr *sechdr)
 {
@@ -1564,6 +1572,11 @@ static void section_rela(const char *modname, struct elf_info *elf,
 			    ELF_R_TYPE(r.r_info) == R_RISCV_SUB32)
 				continue;
 			break;
+		case EM_LOONGARCH:
+			if (!strcmp("__ex_table", fromsec) &&
+			    ELF_R_TYPE(r.r_info) == R_LARCH_SUB32)
+				continue;
+			break;
 		}
 		sym = elf->symtab_start + r_sym;
 		/* Skip special sections */

scripts/recordmcount.c

@@ -38,6 +38,14 @@
 #define R_AARCH64_ABS64	257
 #endif
 
+#ifndef EM_LOONGARCH
+#define EM_LOONGARCH		258
+#define R_LARCH_32			1
+#define R_LARCH_64			2
+#define R_LARCH_MARK_LA			20
+#define R_LARCH_SOP_PUSH_PLT_PCREL	29
+#endif
+
 #define R_ARM_PC24		1
 #define R_ARM_THM_CALL		10
 #define R_ARM_CALL		28
@@ -441,6 +449,28 @@ static int arm64_is_fake_mcount(Elf64_Rel const *rp)
 	return ELF64_R_TYPE(w8(rp->r_info)) != R_AARCH64_CALL26;
 }
 
+static int LARCH32_is_fake_mcount(Elf32_Rel const *rp)
+{
+	switch (ELF64_R_TYPE(w(rp->r_info))) {
+	case R_LARCH_MARK_LA:
+	case R_LARCH_SOP_PUSH_PLT_PCREL:
+		return 0;
+	}
+
+	return 1;
+}
+
+static int LARCH64_is_fake_mcount(Elf64_Rel const *rp)
+{
+	switch (ELF64_R_TYPE(w(rp->r_info))) {
+	case R_LARCH_MARK_LA:
+	case R_LARCH_SOP_PUSH_PLT_PCREL:
+		return 0;
+	}
+
+	return 1;
+}
+
 /* 64-bit EM_MIPS has weird ELF64_Rela.r_info.
  * http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf
  * We interpret Table 29 Relocation Operation (Elf64_Rel, Elf64_Rela) [p.40]
@@ -558,6 +588,7 @@ static int do_file(char const *const fname)
 		break;
 	case EM_IA_64:	reltype = R_IA64_IMM64; break;
 	case EM_MIPS:	/* reltype: e_class    */ break;
+	case EM_LOONGARCH:	/* reltype: e_class    */ break;
 	case EM_PPC:	reltype = R_PPC_ADDR32; break;
 	case EM_PPC64:	reltype = R_PPC64_ADDR64; break;
 	case EM_S390:	/* reltype: e_class    */ break;
@@ -589,6 +620,10 @@ static int do_file(char const *const fname)
 			reltype = R_MIPS_32;
 			is_fake_mcount32 = MIPS32_is_fake_mcount;
 		}
+		if (w2(ehdr->e_machine) == EM_LOONGARCH) {
+			reltype = R_LARCH_32;
+			is_fake_mcount32 = LARCH32_is_fake_mcount;
+		}
 		if (do32(ehdr, fname, reltype) < 0)
 			goto out;
 		break;
@@ -610,6 +645,10 @@ static int do_file(char const *const fname)
 			Elf64_r_info = MIPS64_r_info;
 			is_fake_mcount64 = MIPS64_is_fake_mcount;
 		}
+		if (w2(ghdr->e_machine) == EM_LOONGARCH) {
+			reltype = R_LARCH_64;
+			is_fake_mcount64 = LARCH64_is_fake_mcount;
+		}
 		if (do64(ghdr, fname, reltype) < 0)
 			goto out;
 		break;

scripts/sorttable.c

@@ -304,6 +304,7 @@ static int do_file(char const *const fname, void *addr)
 	switch (r2(&ehdr->e_machine)) {
 	case EM_386:
 	case EM_AARCH64:
+	case EM_LOONGARCH:
 	case EM_RISCV:
 	case EM_S390:
 	case EM_X86_64:
@@ -317,7 +318,6 @@ static int do_file(char const *const fname, void *addr)
 	case EM_ARCOMPACT:
 	case EM_ARCV2:
 	case EM_ARM:
-	case EM_LOONGARCH:
 	case EM_MICROBLAZE:
 	case EM_MIPS:
 	case EM_XTENSA: