Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Peter Anvin:
 "Another set of fixes, the biggest bit of this is yet another tweak to
  the UEFI anti-bricking code; apparently we finally got some feedback
  from Samsung as to what makes at least their systems fail.  This set
  should actually fix the boot regressions that some other systems (e.g.
  SGI) have exhibited.

  Other than that, there is a patch to avoid a panic with particularly
  unhappy memory layouts and two minor protocol fixes which may or may
  not be manifest bugs"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Fix typo in kexec register clearing
  x86, relocs: Move __vvar_page from S_ABS to S_REL
  Modify UEFI anti-bricking code
  x86: Fix adjust_range_size_mask calling position

arch/x86/boot/compressed/eboot.c

@@ -251,51 +251,6 @@ static void find_bits(unsigned long mask, u8 *pos, u8 *size)
 	*size = len;
 }
 
-static efi_status_t setup_efi_vars(struct boot_params *params)
-{
-	struct setup_data *data;
-	struct efi_var_bootdata *efidata;
-	u64 store_size, remaining_size, var_size;
-	efi_status_t status;
-
-	if (sys_table->runtime->hdr.revision < EFI_2_00_SYSTEM_TABLE_REVISION)
-		return EFI_UNSUPPORTED;
-
-	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
-
-	while (data && data->next)
-		data = (struct setup_data *)(unsigned long)data->next;
-
-	status = efi_call_phys4((void *)sys_table->runtime->query_variable_info,
-				EFI_VARIABLE_NON_VOLATILE |
-				EFI_VARIABLE_BOOTSERVICE_ACCESS |
-				EFI_VARIABLE_RUNTIME_ACCESS, &store_size,
-				&remaining_size, &var_size);
-
-	if (status != EFI_SUCCESS)
-		return status;
-
-	status = efi_call_phys3(sys_table->boottime->allocate_pool,
-				EFI_LOADER_DATA, sizeof(*efidata), &efidata);
-
-	if (status != EFI_SUCCESS)
-		return status;
-
-	efidata->data.type = SETUP_EFI_VARS;
-	efidata->data.len = sizeof(struct efi_var_bootdata) -
-		sizeof(struct setup_data);
-	efidata->data.next = 0;
-	efidata->store_size = store_size;
-	efidata->remaining_size = remaining_size;
-	efidata->max_var_size = var_size;
-
-	if (data)
-		data->next = (unsigned long)efidata;
-	else
-		params->hdr.setup_data = (unsigned long)efidata;
-
-}
-
 static efi_status_t setup_efi_pci(struct boot_params *params)
 {
 	efi_pci_io_protocol *pci;
@@ -1202,8 +1157,6 @@ struct boot_params *efi_main(void *handle, efi_system_table_t *_table,
 
 	setup_graphics(boot_params);
 
-	setup_efi_vars(boot_params);
-
 	setup_efi_pci(boot_params);
 
 	status = efi_call_phys3(sys_table->boottime->allocate_pool,

arch/x86/include/asm/efi.h

@@ -102,13 +102,6 @@ extern void efi_call_phys_epilog(void);
 extern void efi_unmap_memmap(void);
 extern void efi_memory_uc(u64 addr, unsigned long size);
 
-struct efi_var_bootdata {
-	struct setup_data data;
-	u64 store_size;
-	u64 remaining_size;
-	u64 max_var_size;
-};
-
 #ifdef CONFIG_EFI
 
 static inline bool efi_is_native(void)

arch/x86/include/uapi/asm/bootparam.h

@@ -6,7 +6,6 @@
 #define SETUP_E820_EXT			1
 #define SETUP_DTB			2
 #define SETUP_PCI			3
-#define SETUP_EFI_VARS			4
 
 /* ram_size flags */
 #define RAMDISK_IMAGE_START_MASK	0x07FF

arch/x86/kernel/relocate_kernel_64.S

@@ -160,7 +160,7 @@ identity_mapped:
 	xorq    %rbp, %rbp
 	xorq	%r8,  %r8
 	xorq	%r9,  %r9
-	xorq	%r10, %r9
+	xorq	%r10, %r10
 	xorq	%r11, %r11
 	xorq	%r12, %r12
 	xorq	%r13, %r13

arch/x86/mm/init.c

@@ -277,6 +277,9 @@ static int __meminit split_mem_range(struct map_range *mr, int nr_range,
 	end_pfn = limit_pfn;
 	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
 
+	if (!after_bootmem)
+		adjust_range_page_size_mask(mr, nr_range);
+
 	/* try to merge same page size and continuous */
 	for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
 		unsigned long old_start;
@@ -291,9 +294,6 @@ static int __meminit split_mem_range(struct map_range *mr, int nr_range,
 		nr_range--;
 	}
 
-	if (!after_bootmem)
-		adjust_range_page_size_mask(mr, nr_range);
-
 	for (i = 0; i < nr_range; i++)
 		printk(KERN_DEBUG " [mem %#010lx-%#010lx] page %s\n",
 				mr[i].start, mr[i].end - 1,

arch/x86/platform/efi/efi.c

@@ -42,7 +42,6 @@
 #include <linux/io.h>
 #include <linux/reboot.h>
 #include <linux/bcd.h>
-#include <linux/ucs2_string.h>
 
 #include <asm/setup.h>
 #include <asm/efi.h>
@@ -54,12 +53,12 @@
 
 #define EFI_DEBUG	1
 
-/*
- * There's some additional metadata associated with each
- * variable. Intel's reference implementation is 60 bytes - bump that
- * to account for potential alignment constraints
- */
-#define VAR_METADATA_SIZE 64
+#define EFI_MIN_RESERVE 5120
+
+#define EFI_DUMMY_GUID \
+	EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9)
+
+static efi_char16_t efi_dummy_name[6] = { 'D', 'U', 'M', 'M', 'Y', 0 };
 
 struct efi __read_mostly efi = {
 	.mps        = EFI_INVALID_TABLE_ADDR,
@@ -79,13 +78,6 @@ struct efi_memory_map memmap;
 static struct efi efi_phys __initdata;
 static efi_system_table_t efi_systab __initdata;
 
-static u64 efi_var_store_size;
-static u64 efi_var_remaining_size;
-static u64 efi_var_max_var_size;
-static u64 boot_used_size;
-static u64 boot_var_size;
-static u64 active_size;
-
 unsigned long x86_efi_facility;
 
 /*
@@ -188,53 +180,8 @@ static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 					       efi_char16_t *name,
 					       efi_guid_t *vendor)
 {
-	efi_status_t status;
-	static bool finished = false;
-	static u64 var_size;
-
-	status = efi_call_virt3(get_next_variable,
+	return efi_call_virt3(get_next_variable,
 			      name_size, name, vendor);
-
-	if (status == EFI_NOT_FOUND) {
-		finished = true;
-		if (var_size < boot_used_size) {
-			boot_var_size = boot_used_size - var_size;
-			active_size += boot_var_size;
-		} else {
-			printk(KERN_WARNING FW_BUG  "efi: Inconsistent initial sizes\n");
-		}
-	}
-
-	if (boot_used_size && !finished) {
-		unsigned long size = 0;
-		u32 attr;
-		efi_status_t s;
-		void *tmp;
-
-		s = virt_efi_get_variable(name, vendor, &attr, &size, NULL);
-
-		if (s != EFI_BUFFER_TOO_SMALL || !size)
-			return status;
-
-		tmp = kmalloc(size, GFP_ATOMIC);
-
-		if (!tmp)
-			return status;
-
-		s = virt_efi_get_variable(name, vendor, &attr, &size, tmp);
-
-		if (s == EFI_SUCCESS && (attr & EFI_VARIABLE_NON_VOLATILE)) {
-			var_size += size;
-			var_size += ucs2_strsize(name, 1024);
-			active_size += size;
-			active_size += VAR_METADATA_SIZE;
-			active_size += ucs2_strsize(name, 1024);
-		}
-
-		kfree(tmp);
-	}
-
-	return status;
 }
 
 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
@@ -243,34 +190,9 @@ static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 					  unsigned long data_size,
 					  void *data)
 {
-	efi_status_t status;
-	u32 orig_attr = 0;
-	unsigned long orig_size = 0;
-
-	status = virt_efi_get_variable(name, vendor, &orig_attr, &orig_size,
-				       NULL);
-
-	if (status != EFI_BUFFER_TOO_SMALL)
-		orig_size = 0;
-
-	status = efi_call_virt5(set_variable,
+	return efi_call_virt5(set_variable,
 			      name, vendor, attr,
 			      data_size, data);
-
-	if (status == EFI_SUCCESS) {
-		if (orig_size) {
-			active_size -= orig_size;
-			active_size -= ucs2_strsize(name, 1024);
-			active_size -= VAR_METADATA_SIZE;
-		}
-		if (data_size) {
-			active_size += data_size;
-			active_size += ucs2_strsize(name, 1024);
-			active_size += VAR_METADATA_SIZE;
-		}
-	}
-
-	return status;
 }
 
 static efi_status_t virt_efi_query_variable_info(u32 attr,
@@ -786,9 +708,6 @@ void __init efi_init(void)
 	char vendor[100] = "unknown";
 	int i = 0;
 	void *tmp;
-	struct setup_data *data;
-	struct efi_var_bootdata *efi_var_data;
-	u64 pa_data;
 
 #ifdef CONFIG_X86_32
 	if (boot_params.efi_info.efi_systab_hi ||
@@ -806,22 +725,6 @@ void __init efi_init(void)
 	if (efi_systab_init(efi_phys.systab))
 		return;
 
-	pa_data = boot_params.hdr.setup_data;
-	while (pa_data) {
-		data = early_ioremap(pa_data, sizeof(*efi_var_data));
-		if (data->type == SETUP_EFI_VARS) {
-			efi_var_data = (struct efi_var_bootdata *)data;
-
-			efi_var_store_size = efi_var_data->store_size;
-			efi_var_remaining_size = efi_var_data->remaining_size;
-			efi_var_max_var_size = efi_var_data->max_var_size;
-		}
-		pa_data = data->next;
-		early_iounmap(data, sizeof(*efi_var_data));
-	}
-
-	boot_used_size = efi_var_store_size - efi_var_remaining_size;
-
 	set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 
 	/*
@@ -1085,6 +988,13 @@ void __init efi_enter_virtual_mode(void)
 		runtime_code_page_mkexec();
 
 	kfree(new_memmap);
+
+	/* clean DUMMY object */
+	efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
+			 EFI_VARIABLE_NON_VOLATILE |
+			 EFI_VARIABLE_BOOTSERVICE_ACCESS |
+			 EFI_VARIABLE_RUNTIME_ACCESS,
+			 0, NULL);
 }
 
 /*
@@ -1136,33 +1046,65 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
 	efi_status_t status;
 	u64 storage_size, remaining_size, max_size;
 
+	if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
+		return 0;
+
 	status = efi.query_variable_info(attributes, &storage_size,
 					 &remaining_size, &max_size);
 	if (status != EFI_SUCCESS)
 		return status;
 
-	if (!max_size && remaining_size > size)
-		printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
-			    " is returning MaxVariableSize=0\n");
 	/*
 	 * Some firmware implementations refuse to boot if there's insufficient
 	 * space in the variable store. We account for that by refusing the
 	 * write if permitting it would reduce the available space to under
-	 * 50%. However, some firmware won't reclaim variable space until
-	 * after the used (not merely the actively used) space drops below
-	 * a threshold. We can approximate that case with the value calculated
-	 * above. If both the firmware and our calculations indicate that the
-	 * available space would drop below 50%, refuse the write.
+	 * 5KB. This figure was provided by Samsung, so should be safe.
 	 */
+	if ((remaining_size - size < EFI_MIN_RESERVE) &&
+		!efi_no_storage_paranoia) {
 
-	if (!storage_size || size > remaining_size ||
-	    (max_size && size > max_size))
-		return EFI_OUT_OF_RESOURCES;
+		/*
+		 * Triggering garbage collection may require that the firmware
+		 * generate a real EFI_OUT_OF_RESOURCES error. We can force
+		 * that by attempting to use more space than is available.
+		 */
+		unsigned long dummy_size = remaining_size + 1024;
+		void *dummy = kmalloc(dummy_size, GFP_ATOMIC);
+
+		status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
+					  EFI_VARIABLE_NON_VOLATILE |
+					  EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					  EFI_VARIABLE_RUNTIME_ACCESS,
+					  dummy_size, dummy);
 
-	if (!efi_no_storage_paranoia &&
-	    ((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
-	     (remaining_size - size < storage_size / 2)))
+		if (status == EFI_SUCCESS) {
+			/*
+			 * This should have failed, so if it didn't make sure
+			 * that we delete it...
+			 */
+			efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
+					 EFI_VARIABLE_NON_VOLATILE |
+					 EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					 EFI_VARIABLE_RUNTIME_ACCESS,
+					 0, dummy);
+		}
+
+		/*
+		 * The runtime code may now have triggered a garbage collection
+		 * run, so check the variable info again
+		 */
+		status = efi.query_variable_info(attributes, &storage_size,
+						 &remaining_size, &max_size);
+
+		if (status != EFI_SUCCESS)
+			return status;
+
+		/*
+		 * There still isn't enough room, so return an error
+		 */
+		if (remaining_size - size < EFI_MIN_RESERVE)
 			return EFI_OUT_OF_RESOURCES;
+	}
 
 	return EFI_SUCCESS;
 }

arch/x86/tools/relocs.c

@@ -42,9 +42,6 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
 	"^(xen_irq_disable_direct_reloc$|"
 	"xen_save_fl_direct_reloc$|"
 	"VDSO|"
-#if ELF_BITS == 64
-	"__vvar_page|"
-#endif
 	"__crc_)",
 
 /*
@@ -72,6 +69,7 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
 	"__per_cpu_load|"
 	"init_per_cpu__.*|"
 	"__end_rodata_hpage_align|"
+	"__vvar_page|"
 #endif
 	"_end)$"
 };