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 instruction 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.

1) ftrace_make_call, ftrace_make_nop (in kernel/ftrace.c)
   The two functions turn each recorded call site of filtered functions
   into a call to ftrace_caller or nops.

2) ftracce_update_ftrace_func (in kernel/ftrace.c)
   turns the nops at ftrace_call into a call to a generic entry for
   function tracers.

3) ftrace_caller (in kernel/mcount_dyn.S)
   The entry where each _mcount call sites calls to once they are
   filtered to be traced.
Co-developed-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Recordmcount utility under scripts is run, after compiling each object,
to find out all the locations of calling _mcount() and put them into
specific seciton named __mcount_loc.

Then the linker collects all such information into a table in the kernel
image (between __start_mcount_loc and __stop_mcount_loc) for later use
by ftrace.

This patch adds LoongArch specific definitions to identify such locations.
And on LoongArch, only the C version is used to build the kernel now that
CONFIG_HAVE_C_RECORDMCOUNT is on.
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

This patch contains basic ftrace support for LoongArch. Specifically,
function tracer (HAVE_FUNCTION_TRACER), function graph tracer (HAVE_
FUNCTION_GRAPH_TRACER) are implemented following the instructions in
Documentation/trace/ftrace-design.txt.

Use `-pg` makes stub like a child function `void _mcount(void *ra)`.
Thus, it can be seen store RA and alloc stack before `call _mcount`.
Find `alloc stack` at first, and then find `store RA`.

Note that the functions in both inst.c and time.c should not be hooked
with the compiler's -pg option: to prevent infinite self-referencing for
the former, and to ignore early setup stuff for the latter.
Co-developed-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Instead of saving a pointer to the .got, .plt and .plt_idx sections to
apply {got,plt}-based relocations, save and use their section indices
instead.

The mod->arch.{core,init}.{got,plt} pointers were problematic for live-
patch because they pointed within temporary section headers (provided by
the module loader via info->sechdrs) that would be freed after module
load. Since livepatch modules may need to apply relocations post-module-
load (for example, to patch a module that is loaded later), using section
indices to offset into the section headers (instead of accessing them
through a saved pointer) allows livepatch modules on LoongArch to pass
in their own copy of the section headers to apply_relocate_add() to
apply delayed relocations.

The method used is same as commit c8ebf64e ("arm64/module: use plt
section indices for relocations").
Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Add basic stack protector support similar to other architectures. A
constant canary value is set at boot time, and with help of compiler's
-fstack-protector we can detect stack corruption.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Add hibernation (Suspend to Disk, aka ACPI S4) support for LoongArch.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Add suspend (Suspend To RAM, aka ACPI S3) support for LoongArch.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Similar to commit 6d0068ad ("MIPS: Loongson64: Process ISA
Node in DeviceTree"), we process ISA node in DeviceTree for FDT-based
systems.

Previously, we are hardcoding reserved ISA I/O Space in, now we are
processing it I/O via DeviceTree directly. The ranges property of ISA
node is used to determine the size and address of reserved I/O space.
Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Since commit 40cd01a9("efi/loongarch: libstub: remove dependency on
flattened DT"), we can parse the FDT from efi system table.

And now, LoongArch is coming to support booting with FDT, so we add the
relevant booting support as well as parameter parsing.
Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Use the alternative to optimize common libraries according whether CPU
has UAL (hardware unaligned access support) feature, including memset(),
memcopy(), memmove(), copy_user() and clear_user().

We have tested UnixBench on a Loongson-3A5000 quad-core machine (1.6GHz):

1, One copy, before patch:

System Benchmarks Index Values               BASELINE       RESULT    INDEX
Dhrystone 2 using register variables         116700.0    9566582.0    819.8
Double-Precision Whetstone                       55.0       2805.3    510.1
Execl Throughput                                 43.0       2120.0    493.0
File Copy 1024 bufsize 2000 maxblocks          3960.0     209833.0    529.9
File Copy 256 bufsize 500 maxblocks            1655.0      89400.0    540.2
File Copy 4096 bufsize 8000 maxblocks          5800.0     320036.0    551.8
Pipe Throughput                               12440.0     340624.0    273.8
Pipe-based Context Switching                   4000.0     109939.1    274.8
Process Creation                                126.0       4728.7    375.3
Shell Scripts (1 concurrent)                     42.4       2223.1    524.3
Shell Scripts (8 concurrent)                      6.0        883.1   1471.9
System Call Overhead                          15000.0     518639.1    345.8
                                                                   ========
System Benchmarks Index Score                                         500.2

2, One copy, after patch:

System Benchmarks Index Values               BASELINE       RESULT    INDEX
Dhrystone 2 using register variables         116700.0    9567674.7    819.9
Double-Precision Whetstone                       55.0       2805.5    510.1
Execl Throughput                                 43.0       2392.7    556.4
File Copy 1024 bufsize 2000 maxblocks          3960.0     417804.0   1055.1
File Copy 256 bufsize 500 maxblocks            1655.0     112909.5    682.2
File Copy 4096 bufsize 8000 maxblocks          5800.0    1255207.4   2164.2
Pipe Throughput                               12440.0     555712.0    446.7
Pipe-based Context Switching                   4000.0      99964.5    249.9
Process Creation                                126.0       5192.5    412.1
Shell Scripts (1 concurrent)                     42.4       2302.4    543.0
Shell Scripts (8 concurrent)                      6.0        919.6   1532.6
System Call Overhead                          15000.0     511159.3    340.8
                                                                   ========
System Benchmarks Index Score                                         640.1

3, Four copies, before patch:

System Benchmarks Index Values               BASELINE       RESULT    INDEX
Dhrystone 2 using register variables         116700.0   38268610.5   3279.2
Double-Precision Whetstone                       55.0      11222.2   2040.4
Execl Throughput                                 43.0       7892.0   1835.3
File Copy 1024 bufsize 2000 maxblocks          3960.0     235149.6    593.8
File Copy 256 bufsize 500 maxblocks            1655.0      74959.6    452.9
File Copy 4096 bufsize 8000 maxblocks          5800.0     545048.5    939.7
Pipe Throughput                               12440.0    1337359.0   1075.0
Pipe-based Context Switching                   4000.0     473663.9   1184.2
Process Creation                                126.0      17491.2   1388.2
Shell Scripts (1 concurrent)                     42.4       6865.7   1619.3
Shell Scripts (8 concurrent)                      6.0       1015.9   1693.1
System Call Overhead                          15000.0    1899535.2   1266.4
                                                                   ========
System Benchmarks Index Score                                        1278.3

4, Four copies, after patch:

System Benchmarks Index Values               BASELINE       RESULT    INDEX
Dhrystone 2 using register variables         116700.0   38272815.5   3279.6
Double-Precision Whetstone                       55.0      11222.8   2040.5
Execl Throughput                                 43.0       8839.2   2055.6
File Copy 1024 bufsize 2000 maxblocks          3960.0     313912.9    792.7
File Copy 256 bufsize 500 maxblocks            1655.0      80976.1    489.3
File Copy 4096 bufsize 8000 maxblocks          5800.0    1176594.3   2028.6
Pipe Throughput                               12440.0    2100941.9   1688.9
Pipe-based Context Switching                   4000.0     476696.4   1191.7
Process Creation                                126.0      18394.7   1459.9
Shell Scripts (1 concurrent)                     42.4       7172.2   1691.6
Shell Scripts (8 concurrent)                      6.0       1058.3   1763.9
System Call Overhead                          15000.0    1874714.7   1249.8
                                                                   ========
System Benchmarks Index Score                                        1488.8
Signed-off-by: Jun Yi <yijun@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Introduce the "alternative" mechanism from ARM64 and x86 for LoongArch
to apply runtime patching. The main purpose of this patch is to provide
a framework. In future we can use this mechanism (i.e., the ALTERNATIVE
and ALTERNATIVE_2 macros) to optimize hotspot functions according to cpu
features.
Signed-off-by: Jun Yi <yijun@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Loongson-2 series (Loongson-2K500, Loongson-2K1000) don't support
unaligned access in hardware, while Loongson-3 series (Loongson-3A5000,
Loongson-3C5000) are configurable whether support unaligned access in
hardware. This patch add unaligned access emulation for those LoongArch
processors without hardware support.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Inspired by commit 80083428("bpf, arm64: Add BPF exception tables"),
do similar to LoongArch to add BPF exception tables.

When a tracing BPF program attempts to read memory without using the
bpf_probe_read() helper, the verifier marks the load instruction with
the BPF_PROBE_MEM flag. Since the LoongArch JIT does not currently
recognize this flag it falls back to the interpreter.

Add support for BPF_PROBE_MEM, by appending an exception table to the
BPF program. If the load instruction causes a data abort, the fixup
infrastructure finds the exception table and fixes up the fault, by
clearing the destination register and jumping over the faulting
instruction.

To keep the compact exception table entry format, inspect the pc in
fixup_exception(). A more generic solution would add a "handler" field
to the table entry, like on x86, s390 and arm64, etc.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Use the `.L_xxx` label to improve fixup code and then remove the .fixup
section usage.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Inspired by commit 2e77a62c("arm64: extable: add a dedicated uaccess
handler"), do similar to LoongArch to add a dedicated uaccess exception
handler to update registers in exception context and subsequently return
back into the function which faulted, so we remove the need for fixups
specialized to each faulting instruction.

Add gpr-num.h here because we need to map the same GPR names to integer
constants, so that we can use this to build meta-data for the exception
fixups.

The compiler treats gpr 0 as zero rather than $r0, so set it separately
to .L__gpr_num_zero, otherwise the following assembly error will occurs:

{standard input}: Assembler messages:
{standard input}:1074: Error: invalid operands (*UND* and *ABS* sections) for `<<'
{standard input}:1160: Error: invalid operands (*UND* and *ABS* sections) for `<<'
make[1]: *** [scripts/Makefile.build:249: fs/fcntl.o] Error 1
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

This is a LoongArch port of commit d6e2cc56 ("arm64: extable: add
`type` and `data` fields").

Subsequent patches will add specialized handlers for fixups, in addition
to the simple PC fixup we have today. In preparation, this patch adds a
new `type` field to struct exception_table_entry, and uses this to
distinguish the fixup and other cases. A `data` field is also added so
that subsequent patches can associate data specific to each exception
site (e.g. register numbers).

Handlers are named ex_handler_*() for consistency, following the example
of x86. At the same time, get_ex_fixup() is split out into a helper so
that it can be used by other ex_handler_*() functions in the subsequent
patches.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Similar to other architectures such as arm64, x86, riscv and so on, use
offsets relative to the exception table entry values rather than their
absolute addresses for both the exception location and the fixup.

However, LoongArch label difference because it will actually produce two
relocations, a pair of R_LARCH_ADD32 and R_LARCH_SUB32. Take simple code
below for example:

$ cat test_ex_table.S
.section .text
1:
        nop
.section __ex_table,"a"
        .balign 4
        .long (1b - .)
.previous

$ loongarch64-unknown-linux-gnu-gcc -c test_ex_table.S
$ loongarch64-unknown-linux-gnu-readelf -Wr test_ex_table.o

Relocation section '.rela__ex_table' at offset 0x100 contains 2 entries:
    Offset            Info             Type         Symbol's Value   Symbol's Name + Addend
0000000000000000 0000000600000032 R_LARCH_ADD32    0000000000000000  .L1^B1 + 0
0000000000000000 0000000500000037 R_LARCH_SUB32    0000000000000000  L0^A + 0

The modpost will complain the R_LARCH_SUB32 relocation, so we need to
patch modpost.c to skip this relocation for .rela__ex_table section.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Consolidate all the __ex_table constuction code with a _ASM_EXTABLE or
_asm_extable helper.

There should be no functional change as a result of this patch.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch architecture changes for 6.2 depend on the acpi and irqchip
changes to work, so merge them to create a base.

Merge ACPI fan driver fixes, ACPI PCC driver fixes, miscellaneous ACPI
cleanups and PNP updates for 6.2-rc1:

 - Make the ACPI fan driver use sysfs_emit_at() in its sysfs interface
   code (ye xingchen).

 - Fix the _FIF package extraction failure handling in the ACPI fan
   driver (Hanjun Guo).

 - Fix the PCC mailbox handling error code path (Huisong Li).

 - Avoid using PCC Opregions if there is no platform interrupt allocated
   for this purpose (Huisong Li).

 - Use sysfs_emit() instead of scnprintf() in the ACPI PAD driver and
   CPPC library (ye xingchen).

 - Fix some kernel-doc issues in the ACPI GSI processing code (Xiongfeng
   Wang).

 - Fix name memory leak in pnp_alloc_dev() (Yang Yingliang).

 - Do not disable PNP devices on suspend when they cannot be re-enabled
   on resume (Hans de Goede).

* acpi-fan:
  ACPI: fan: Convert to use sysfs_emit_at() API
  ACPI: fan: Bail out if extract package failed

* acpi-pcc:
  mailbox: pcc: Reset pcc_chan_count to zero in case of PCC probe failure
  ACPI: PCC: Setup PCC Opregion handler only if platform interrupt is available

* acpi-misc:
  ACPI: use sysfs_emit() instead of scnprintf()
  ACPI: irq: Fix some kernel-doc issues

* pnp:
  PNP: Do not disable devices on suspend when they cannot be re-enabled on resume
  PNP: fix name memory leak in pnp_alloc_dev()

Make ACPI APEI updates, x86-specific ACPI updates, ACPI battery driver
fix and ACPI PFRU/T driver fixes for 6.2-rc1:

 - Drop unsetting ACPI APEI driver data on remove (Uwe Kleine-König).

 - Use xchg_release() instead of cmpxchg() for updating new GHES cache
   slots (Ard Biesheuvel).

 - Clean up the ACPI APEI code (Sudeep Holla, Christophe JAILLET, Jay Lu).

 - Add new I2C device enumeration quirks for Medion Lifetab S10346 and
   Lenovo Yoga Tab 3 Pro (YT3-X90F) (Hans de Goede).

 - Make the ACPI battery driver notify user space about adding new
   battery hooks and removing the existing ones (Armin Wolf).

 - Modify the pfr_update and pfr_telemetry drivers to use ACPI_FREE()
   for freeing acpi_object structures to help diagnostics (Wang ShaoBo).

* acpi-apei:
  ACPI: APEI: EINJ: Refactor available_error_type_show()
  ACPI: APEI: EINJ: Fix formatting errors
  ACPI: APEI: Remove a useless include
  ACPI: APEI: Silence missing prototype warnings
  apei/ghes: Use xchg_release() for updating new cache slot instead of cmpxchg()
  ACPI: APEI: Drop unsetting driver data on remove

* acpi-x86:
  ACPI: x86: Add skip i2c clients quirk for Medion Lifetab S10346
  ACPI: x86: Add skip i2c clients quirk for Lenovo Yoga Tab 3 Pro (YT3-X90F)

* acpi-battery:
  ACPI: battery: Call power_supply_changed() when adding hooks

* acpi-pfrut:
  ACPI: pfr_update: use ACPI_FREE() to free acpi_object
  ACPI: pfr_telemetry: use ACPI_FREE() to free acpi_object

Make ACPI power management changes, ACPI processor driver updates, ACPI
EC driver quirk and ACPI backlight driver updates for 6.2-rc1:

 - Print full name paths of ACPI power resources objects during
   enumeration (Kane Chen).

 - Eliminate a compiler warning regarding a missing function prototype
   in the ACPI power management code (Sudeep Holla).

 - Fix and clean up the ACPI processor driver (Rafael Wysocki, Li Zhong,
   Colin Ian King, Sudeep Holla).

 - Add quirk for the HP Pavilion Gaming 15-cx0041ur to the ACPI EC
   driver (Mia Kanashi).

 - Add some mew ACPI backlight handling quirks and update some existing
   ones (Hans de Goede).

 - Make the ACPI backlight driver prefer the native backlight control
   over vendor backlight control when possible (Hans de Goede).

* acpi-pm:
  ACPI: PM: Silence missing prototype warning
  ACPI: PM: Print full name path while adding power resource

* acpi-processor:
  ACPI: processor: perflib: Adjust acpi_processor_notify_smm() return value
  ACPI: processor: perflib: Rearrange acpi_processor_notify_smm()
  ACPI: processor: perflib: Rearrange unregistration routine
  ACPI: processor: perflib: Drop redundant parentheses
  ACPI: processor: perflib: Adjust white space
  ACPI: processor: idle: Drop unnecessary statements and parens
  ACPI: processor: Silence missing prototype warnings
  ACPI: processor_idle: Silence missing prototype warnings
  ACPI: processor: throttling: remove variable count
  ACPI: processor: idle: Check acpi_fetch_acpi_dev() return value

* acpi-ec:
  ACPI: EC: Add quirk for the HP Pavilion Gaming 15-cx0041ur

* acpi-video:
  ACPI: video: Prefer native over vendor
  ACPI: video: Simplify __acpi_video_get_backlight_type()
  ACPI: video: Add force_native quirk for Sony Vaio VPCY11S1E
  ACPI: video: Add force_vendor quirk for Sony Vaio PCG-FRV35
  ACPI: video: Change Sony Vaio VPCEH3U1E quirk to force_native
  ACPI: video: Change GIGABYTE GB-BXBT-2807 quirk to force_none
  ACPI: video: Add a few bugtracker links to DMI quirks

Merge ACPI changes related to device enumeration, device object
managenet, operation region handling, table parsing and sysfs
interface:

 - Use ZERO_PAGE(0) instead of empty_zero_page in the ACPI device
   enumeration code (Giulio Benetti).

 - Change the return type of the ACPI driver remove callback to void and
   update its users accordingly (Dawei Li).

 - Add general support for FFH address space type and implement the low-
   level part of it for ARM64 (Sudeep Holla).

 - Fix stale comments in the ACPI tables parsing code and make it print
   more messages related to MADT (Hanjun Guo, Huacai Chen).

 - Replace invocations of generic library functions with more kernel-
   specific counterparts in the ACPI sysfs interface (Christophe JAILLET,
   Xu Panda).

* acpi-scan:
  ACPI: scan: substitute empty_zero_page with helper ZERO_PAGE(0)

* acpi-bus:
  ACPI: FFH: Silence missing prototype warnings
  ACPI: make remove callback of ACPI driver void
  ACPI: bus: Fix the _OSC capability check for FFH OpRegion
  arm64: Add architecture specific ACPI FFH Opregion callbacks
  ACPI: Implement a generic FFH Opregion handler

* acpi-tables:
  ACPI: tables: Fix the stale comments for acpi_locate_initial_tables()
  ACPI: tables: Print CORE_PIC information when MADT is parsed

* acpi-sysfs:
  ACPI: sysfs: use sysfs_emit() to instead of scnprintf()
  ACPI: sysfs: Use kstrtobool() instead of strtobool()

Merge ACPICA changes, including bug fixes and cleanups as well as support
for some recently defined data structures, for 6.2-rc1:

 - Make acpi_ex_load_op() match upstream implementation (Rafael Wysocki).
 - Add support for loong_arch-specific APICs in MADT (Huacai Chen).
 - Add support for fixed PCIe wake event (Huacai Chen).
 - Add EBDA pointer sanity checks (Vit Kabele).
 - Avoid accessing VGA memory when EBDA < 1KiB (Vit Kabele).
 - Add CCEL table support to both compiler/disassembler (Kuppuswamy
   Sathyanarayanan).
 - Add a couple of new UUIDs to the known UUID list (Bob Moore).
 - Add support for FFH Opregion special context data (Sudeep Holla).
 - Improve warning message for "invalid ACPI name" (Bob Moore).
 - Add support for CXL 3.0 structures (CXIMS & RDPAS) in the CEDT table
   (Alison Schofield).
 - Prepare IORT support for revision E.e (Robin Murphy).
 - Finish support for the CDAT table (Bob Moore).
 - Fix error code path in acpi_ds_call_control_method() (Rafael Wysocki).
 - Fix use-after-free in acpi_ut_copy_ipackage_to_ipackage() (Li Zetao).
 - Update the version of the ACPICA code in the kernel (Bob Moore).

* acpica:
  ACPICA: Fix use-after-free in acpi_ut_copy_ipackage_to_ipackage()
  ACPICA: Fix error code path in acpi_ds_call_control_method()
  ACPICA: Update version to 20221020
  ACPICA: Add utcksum.o to the acpidump Makefile
  Revert "LoongArch: Provisionally add ACPICA data structures"
  ACPICA: Finish support for the CDAT table
  ACPICA: IORT: Update for revision E.e
  ACPICA: Add CXL 3.0 structures (CXIMS & RDPAS) to the CEDT table
  ACPICA: Improve warning message for "invalid ACPI name"
  ACPICA: Add support for FFH Opregion special context data
  ACPICA: Add a couple of new UUIDs to the known UUID list
  ACPICA: iASL: Add CCEL table to both compiler/disassembler
  ACPICA: Do not touch VGA memory when EBDA < 1ki_b
  ACPICA: Check that EBDA pointer is in valid memory
  ACPICA: Events: Support fixed PCIe wake event
  ACPICA: MADT: Add loong_arch-specific APICs support
  ACPICA: Make acpi_ex_load_op() match upstream

Pull iommu fix from Joerg Roedel:

 - Fix device mask to catch all affected devices in the recently added
   quirk for QAT devices in the Intel VT-d driver.

* tag 'iommu-fix-v6.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Fix buggy QAT device mask

Merge tag 'mm-hotfixes-stable-2022-12-10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "Nine hotfixes.

  Six for MM, three for other areas. Four of these patches address
  post-6.0 issues"

* tag 'mm-hotfixes-stable-2022-12-10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  memcg: fix possible use-after-free in memcg_write_event_control()
  MAINTAINERS: update Muchun Song's email
  mm/gup: fix gup_pud_range() for dax
  mmap: fix do_brk_flags() modifying obviously incorrect VMAs
  mm/swap: fix SWP_PFN_BITS with CONFIG_PHYS_ADDR_T_64BIT on 32bit
  tmpfs: fix data loss from failed fallocate
  kselftests: cgroup: update kmem test precision tolerance
  mm: do not BUG_ON missing brk mapping, because userspace can unmap it
  mailmap: update Matti Vaittinen's email address

Pull ARM fix from Russell King:
 "One further ARM fix for 6.1 from Wang Kefeng, fixing up the handling
  for kfence faults"

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 9278/1: kfence: only handle translation faults

memcg_write_event_control() accesses the dentry->d_name of the specified
control fd to route the write call.  As a cgroup interface file can't be
renamed, it's safe to access d_name as long as the specified file is a
regular cgroup file.  Also, as these cgroup interface files can't be
removed before the directory, it's safe to access the parent too.

Prior to 347c4a87 ("memcg: remove cgroup_event->cft"), there was a
call to __file_cft() which verified that the specified file is a regular
cgroupfs file before further accesses.  The cftype pointer returned from
__file_cft() was no longer necessary and the commit inadvertently dropped
the file type check with it allowing any file to slip through.  With the
invarients broken, the d_name and parent accesses can now race against
renames and removals of arbitrary files and cause use-after-free's.

Fix the bug by resurrecting the file type check in __file_cft().  Now that
cgroupfs is implemented through kernfs, checking the file operations needs
to go through a layer of indirection.  Instead, let's check the superblock
and dentry type.

Link: https://lkml.kernel.org/r/Y5FRm/cfcKPGzWwl@slm.duckdns.org
Fixes: 347c4a87 ("memcg: remove cgroup_event->cft")
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Jann Horn <jannh@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>	[3.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

I'm moving to the @linux.dev account.  Map my old addresses and update it
to my new address.

Link: https://lkml.kernel.org/r/20221208115548.85244-1-songmuchun@bytedance.comSigned-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

For dax pud, pud_huge() returns true on x86. So the function works as long
as hugetlb is configured. However, dax doesn't depend on hugetlb.
Commit 414fd080 ("mm/gup: fix gup_pmd_range() for dax") fixed
devmap-backed huge PMDs, but missed devmap-backed huge PUDs. Fix this as
well.

This fixes the below kernel panic:

general protection fault, probably for non-canonical address 0x69e7c000cc478: 0000 [#1] SMP
	< snip >
Call Trace:
<TASK>
get_user_pages_fast+0x1f/0x40
iov_iter_get_pages+0xc6/0x3b0
? mempool_alloc+0x5d/0x170
bio_iov_iter_get_pages+0x82/0x4e0
? bvec_alloc+0x91/0xc0
? bio_alloc_bioset+0x19a/0x2a0
blkdev_direct_IO+0x282/0x480
? __io_complete_rw_common+0xc0/0xc0
? filemap_range_has_page+0x82/0xc0
generic_file_direct_write+0x9d/0x1a0
? inode_update_time+0x24/0x30
__generic_file_write_iter+0xbd/0x1e0
blkdev_write_iter+0xb4/0x150
? io_import_iovec+0x8d/0x340
io_write+0xf9/0x300
io_issue_sqe+0x3c3/0x1d30
? sysvec_reschedule_ipi+0x6c/0x80
__io_queue_sqe+0x33/0x240
? fget+0x76/0xa0
io_submit_sqes+0xe6a/0x18d0
? __fget_light+0xd1/0x100
__x64_sys_io_uring_enter+0x199/0x880
? __context_tracking_enter+0x1f/0x70
? irqentry_exit_to_user_mode+0x24/0x30
? irqentry_exit+0x1d/0x30
? __context_tracking_exit+0xe/0x70
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fc97c11a7be
	< snip >
</TASK>
---[ end trace 48b2e0e67debcaeb ]---
RIP: 0010:internal_get_user_pages_fast+0x340/0x990
	< snip >
Kernel panic - not syncing: Fatal exception
Kernel Offset: disabled

Link: https://lkml.kernel.org/r/1670392853-28252-1-git-send-email-ssengar@linux.microsoft.com
Fixes: 414fd080 ("mm/gup: fix gup_pmd_range() for dax")
Signed-off-by: John Starks <jostarks@microsoft.com>
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Add more sanity checks to the VMA that do_brk_flags() will expand.  Ensure
the VMA matches basic merge requirements within the function before
calling can_vma_merge_after().

Drop the duplicate checks from vm_brk_flags() since they will be enforced
later.

The old code would expand file VMAs on brk(), which is functionally
wrong and also dangerous in terms of locking because the brk() path
isn't designed for file VMAs and therefore doesn't lock the file
mapping.  Checking can_vma_merge_after() ensures that new anonymous
VMAs can't be merged into file VMAs.

See https://lore.kernel.org/linux-mm/CAG48ez1tJZTOjS_FjRZhvtDA-STFmdw8PEizPDwMGFd_ui0Nrw@mail.gmail.com/

Link: https://lkml.kernel.org/r/20221205192304.1957418-1-Liam.Howlett@oracle.com
Fixes: 2e7ce7d3 ("mm/mmap: change do_brk_flags() to expand existing VMA and add do_brk_munmap()")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Suggested-by: Jann Horn <jannh@google.com>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

We use "unsigned long" to store a PFN in the kernel and phys_addr_t to
store a physical address.

On a 64bit system, both are 64bit wide.  However, on a 32bit system, the
latter might be 64bit wide.  This is, for example, the case on x86 with
PAE: phys_addr_t and PTEs are 64bit wide, while "unsigned long" only spans
32bit.

The current definition of SWP_PFN_BITS without MAX_PHYSMEM_BITS misses
that case, and assumes that the maximum PFN is limited by an 32bit
phys_addr_t.  This implies, that SWP_PFN_BITS will currently only be able
to cover 4 GiB - 1 on any 32bit system with 4k page size, which is wrong.

Let's rely on the number of bits in phys_addr_t instead, but make sure to
not exceed the maximum swap offset, to not make the BUILD_BUG_ON() in
is_pfn_swap_entry() unhappy.  Note that swp_entry_t is effectively an
unsigned long and the maximum swap offset shares that value with the swap
type.

For example, on an 8 GiB x86 PAE system with a kernel config based on
Debian 11.5 (-> CONFIG_FLATMEM=y, CONFIG_X86_PAE=y), we will currently
fail removing migration entries (remove_migration_ptes()), because
mm/page_vma_mapped.c:check_pte() will fail to identify a PFN match as
swp_offset_pfn() wrongly masks off PFN bits.  For example,
split_huge_page_to_list()->...->remap_page() will leave migration entries
in place and continue to unlock the page.

Later, when we stumble over these migration entries (e.g., via
/proc/self/pagemap), pfn_swap_entry_to_page() will BUG_ON() because these
migration entries shouldn't exist anymore and the page was unlocked.

[   33.067591] kernel BUG at include/linux/swapops.h:497!
[   33.067597] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[   33.067602] CPU: 3 PID: 742 Comm: cow Tainted: G            E      6.1.0-rc8+ #16
[   33.067605] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
[   33.067606] EIP: pagemap_pmd_range+0x644/0x650
[   33.067612] Code: 00 00 00 00 66 90 89 ce b9 00 f0 ff ff e9 ff fb ff ff 89 d8 31 db e8 48 c6 52 00 e9 23 fb ff ff e8 61 83 56 00 e9 b6 fe ff ff <0f> 0b bf 00 f0 ff ff e9 38 fa ff ff 3e 8d 74 26 00 55 89 e5 57 31
[   33.067615] EAX: ee394000 EBX: 00000002 ECX: ee394000 EDX: 00000000
[   33.067617] ESI: c1b0ded4 EDI: 00024a00 EBP: c1b0ddb4 ESP: c1b0dd68
[   33.067619] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 EFLAGS: 00010246
[   33.067624] CR0: 80050033 CR2: b7a00000 CR3: 01bbbd20 CR4: 00350ef0
[   33.067625] Call Trace:
[   33.067628]  ? madvise_free_pte_range+0x720/0x720
[   33.067632]  ? smaps_pte_range+0x4b0/0x4b0
[   33.067634]  walk_pgd_range+0x325/0x720
[   33.067637]  ? mt_find+0x1d6/0x3a0
[   33.067641]  ? mt_find+0x1d6/0x3a0
[   33.067643]  __walk_page_range+0x164/0x170
[   33.067646]  walk_page_range+0xf9/0x170
[   33.067648]  ? __kmem_cache_alloc_node+0x2a8/0x340
[   33.067653]  pagemap_read+0x124/0x280
[   33.067658]  ? default_llseek+0x101/0x160
[   33.067662]  ? smaps_account+0x1d0/0x1d0
[   33.067664]  vfs_read+0x90/0x290
[   33.067667]  ? do_madvise.part.0+0x24b/0x390
[   33.067669]  ? debug_smp_processor_id+0x12/0x20
[   33.067673]  ksys_pread64+0x58/0x90
[   33.067675]  __ia32_sys_ia32_pread64+0x1b/0x20
[   33.067680]  __do_fast_syscall_32+0x4c/0xc0
[   33.067683]  do_fast_syscall_32+0x29/0x60
[   33.067686]  do_SYSENTER_32+0x15/0x20
[   33.067689]  entry_SYSENTER_32+0x98/0xf1

Decrease the indentation level of SWP_PFN_BITS and SWP_PFN_MASK to keep it
readable and consistent.

[david@redhat.com: rely on sizeof(phys_addr_t) and min_t() instead]
  Link: https://lkml.kernel.org/r/20221206105737.69478-1-david@redhat.com
[david@redhat.com: use "int" for comparison, as we're only comparing numbers < 64]
  Link: https://lkml.kernel.org/r/1f157500-2676-7cef-a84e-9224ed64e540@redhat.com
Link: https://lkml.kernel.org/r/20221205150857.167583-1-david@redhat.com
Fixes: 0d206b5d ("mm/swap: add swp_offset_pfn() to fetch PFN from swap entry")
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Fix tmpfs data loss when the fallocate system call is interrupted by a
signal, or fails for some other reason.  The partial folio handling in
shmem_undo_range() forgot to consider this unfalloc case, and was liable
to erase or truncate out data which had already been committed earlier.

It turns out that none of the partial folio handling there is appropriate
for the unfalloc case, which just wants to proceed to removal of whole
folios: which find_get_entries() provides, even when partially covered.

Original patch by Rui Wang.

Link: https://lore.kernel.org/linux-mm/33b85d82.7764.1842e9ab207.Coremail.chenguoqic@163.com/
Link: https://lkml.kernel.org/r/a5dac112-cf4b-7af-a33-f386e347fd38@google.com
Fixes: b9a8a419 ("truncate,shmem: Handle truncates that split large folios")
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Guoqi Chen <chenguoqic@163.com>
  Link: https://lore.kernel.org/all/20221101032248.819360-1-kernel@hev.cc/
Cc: Rui Wang <kernel@hev.cc>
Cc: Huacai Chen <chenhuacai@loongson.cn>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: <stable@vger.kernel.org>	[5.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1813e51e ("memcg: increase MEMCG_CHARGE_BATCH to 64") has changed
the batch size while this test case has been left behind. This has led
to a test failure reported by test bot:
not ok 2 selftests: cgroup: test_kmem # exit=1

Update the tolerance for the pcp charges to reflect the
MEMCG_CHARGE_BATCH change to fix this.

[akpm@linux-foundation.org: update comments, per Roman]
Link: https://lkml.kernel.org/r/Y4m8Unt6FhWKC6IH@dhcp22.suse.cz
Fixes: 1813e51e ("memcg: increase MEMCG_CHARGE_BATCH to 64")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: kernel test robot <yujie.liu@intel.com>
  Link: https://lore.kernel.org/oe-lkp/202212010958.c1053bd3-yujie.liu@intel.comAcked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Tested-by: Yujie Liu <yujie.liu@intel.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Michal Koutný" <mkoutny@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The following program will trigger the BUG_ON that this patch removes,
because the user can munmap() mm->brk:

  #include <sys/syscall.h>
  #include <sys/mman.h>
  #include <assert.h>
  #include <unistd.h>

  static void *brk_now(void)
  {
    return (void *)syscall(SYS_brk, 0);
  }

  static void brk_set(void *b)
  {
    assert(syscall(SYS_brk, b) != -1);
  }

  int main(int argc, char *argv[])
  {
    void *b = brk_now();
    brk_set(b + 4096);
    assert(munmap(b - 4096, 4096 * 2) == 0);
    brk_set(b);
    return 0;
  }

Compile that with musl, since glibc actually uses brk(), and then
execute it, and it'll hit this splat:

  kernel BUG at mm/mmap.c:229!
  invalid opcode: 0000 [#1] PREEMPT SMP
  CPU: 12 PID: 1379 Comm: a.out Tainted: G S   U             6.1.0-rc7+ #419
  RIP: 0010:__do_sys_brk+0x2fc/0x340
  Code: 00 00 4c 89 ef e8 04 d3 fe ff eb 9a be 01 00 00 00 4c 89 ff e8 35 e0 fe ff e9 6e ff ff ff 4d 89 a7 20>
  RSP: 0018:ffff888140bc7eb0 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: 00000000007e7000 RCX: ffff8881020fe000
  RDX: ffff8881020fe001 RSI: ffff8881955c9b00 RDI: ffff8881955c9b08
  RBP: 0000000000000000 R08: ffff8881955c9b00 R09: 00007ffc77844000
  R10: 0000000000000000 R11: 0000000000000001 R12: 00000000007e8000
  R13: 00000000007e8000 R14: 00000000007e7000 R15: ffff8881020fe000
  FS:  0000000000604298(0000) GS:ffff88901f700000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000603fe0 CR3: 000000015ba9a005 CR4: 0000000000770ee0
  PKRU: 55555554
  Call Trace:
   <TASK>
   do_syscall_64+0x2b/0x50
   entry_SYSCALL_64_after_hwframe+0x46/0xb0
  RIP: 0033:0x400678
  Code: 10 4c 8d 41 08 4c 89 44 24 10 4c 8b 01 8b 4c 24 08 83 f9 2f 77 0a 4c 8d 4c 24 20 4c 01 c9 eb 05 48 8b>
  RSP: 002b:00007ffc77863890 EFLAGS: 00000212 ORIG_RAX: 000000000000000c
  RAX: ffffffffffffffda RBX: 000000000040031b RCX: 0000000000400678
  RDX: 00000000004006a1 RSI: 00000000007e6000 RDI: 00000000007e7000
  RBP: 00007ffc77863900 R08: 0000000000000000 R09: 00000000007e6000
  R10: 00007ffc77863930 R11: 0000000000000212 R12: 00007ffc77863978
  R13: 00007ffc77863988 R14: 0000000000000000 R15: 0000000000000000
   </TASK>

Instead, just return the old brk value if the original mapping has been
removed.

[akpm@linux-foundation.org: fix changelog, per Liam]
Link: https://lkml.kernel.org/r/20221202162724.2009-1-Jason@zx2c4.com
Fixes: 2e7ce7d3 ("mm/mmap: change do_brk_flags() to expand existing VMA and add do_brk_munmap()")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The email backend used by ROHM keeps labeling patches as spam.  This can
result in missing the patches.

Switch my mail address from a company mail to a personal one.

Link: https://lkml.kernel.org/r/8f4498b66fedcbded37b3b87e0c516e659f8f583.1669912977.git.mazziesaccount@gmail.comSigned-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Suggested-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Anup Patel <anup@brainfault.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Atish Patra <atishp@atishpatra.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Ben Widawsky <bwidawsk@kernel.org>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Kirill Tkhai <tkhai@ya.ru>
Cc: Qais Yousef <qyousef@layalina.io>
Cc: Vasily Averin <vasily.averin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Pull media fix from Mauro Carvalho Chehab:
 "A v4l-core fix related to validating DV timings related to video
  blanking values"

* tag 'media/v6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  media: v4l2-dv-timings.c: fix too strict blanking sanity checks

Pull ARM SoC fix from Arnd Bergmann:
 "One more last minute revert for a boot regression that was found on
  the popular colibri-imx7"

* tag 'soc-fixes-6.1-6' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  Revert "ARM: dts: imx7: Fix NAND controller size-cells"

Pull drm fixes from Dave Airlie:
 "Last set of fixes for final, scattered bunch of fixes, two amdgpu, one
  vmwgfx, and some misc others.

  amdgpu:
   - S0ix fix
   - DCN 3.2 array out of bounds fix

  shmem:
   - Fixes to shmem-helper error paths

  bridge:
   - Fix polarity bug in bridge/ti-sn65dsi86

  dw-hdmi:
   - Prefer 8-bit RGB fallback before any YUV mode in dw-hdmi, since
     some panels lie about YUV support

  vmwgfx:
   - Stop using screen objects when SEV is active"

* tag 'drm-fixes-2022-12-09' of git://anongit.freedesktop.org/drm/drm:
  drm/amd/display: fix array index out of bound error in DCN32 DML
  drm/amdgpu/sdma_v4_0: turn off SDMA ring buffer in the s2idle suspend
  drm/vmwgfx: Don't use screen objects when SEV is active
  drm/shmem-helper: Avoid vm_open error paths
  drm/shmem-helper: Remove errant put in error path
  drm: bridge: dw_hdmi: fix preference of RGB modes over YUV420
  drm/bridge: ti-sn65dsi86: Fix output polarity setting bug
  drm/vmwgfx: Fix race issue calling pin_user_pages