EFI changes for v4.6

index 0010c78c4998..7bb206f73915 100644
@@ -3,6 +3,7 @@
 
 #include <asm/fpu/api.h>
 #include <asm/pgtable.h>
+#include <asm/tlb.h>
 
 /*
  * We map the EFI regions needed for runtime services non-contiguously,

@@ -64,6 +65,17 @@ extern u64 asmlinkage efi_call(void *fp, ...);
 
 #define efi_call_phys(f, args...)		efi_call((f), args)
 
+/*
+ * Scratch space used for switching the pagetable in the EFI stub
+ */
+struct efi_scratch {
+	u64	r15;
+	u64	prev_cr3;
+	pgd_t	*efi_pgt;
+	bool	use_pgd;
+	u64	phys_stack;
+} __packed;
+
 #define efi_call_virt(f, ...)						\
 ({									\
 	efi_status_t __s;						\

@@ -71,7 +83,20 @@ extern u64 asmlinkage efi_call(void *fp, ...);
 	efi_sync_low_kernel_mappings();					\
 	preempt_disable();						\
 	__kernel_fpu_begin();						\
+									\
+	if (efi_scratch.use_pgd) {					\
+		efi_scratch.prev_cr3 = read_cr3();			\
+		write_cr3((unsigned long)efi_scratch.efi_pgt);		\
+		__flush_tlb_all();					\
+	}								\
+									\
 	__s = efi_call((void *)efi.systab->runtime->f, __VA_ARGS__);	\
+									\
+	if (efi_scratch.use_pgd) {					\
+		write_cr3(efi_scratch.prev_cr3);			\
+		__flush_tlb_all();					\
+	}								\
+									\
 	__kernel_fpu_end();						\
 	preempt_enable();						\
 	__s;								\

@@ -111,11 +136,12 @@ extern void __init efi_memory_uc(u64 addr, unsigned long size);
 extern void __init efi_map_region(efi_memory_desc_t *md);
 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
 extern void efi_sync_low_kernel_mappings(void);
+extern int __init efi_alloc_page_tables(void);
 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
 extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
 extern void __init old_map_region(efi_memory_desc_t *md);
 extern void __init runtime_code_page_mkexec(void);
-extern void __init efi_runtime_mkexec(void);
+extern void __init efi_runtime_update_mappings(void);
 extern void __init efi_dump_pagetable(void);
 extern void __init efi_apply_memmap_quirks(void);
 extern int __init efi_reuse_config(u64 tables, int nr_tables);

index 2440814b0069..fcf8e290740a 100644
@@ -909,16 +909,25 @@ static void populate_pte(struct cpa_data *cpa,
 
 	pte = pte_offset_kernel(pmd, start);
 
-	while (num_pages-- && start < end) {
+	/*
+	 * Set the GLOBAL flags only if the PRESENT flag is
+	 * set otherwise pte_present will return true even on
+	 * a non present pte. The canon_pgprot will clear
+	 * _PAGE_GLOBAL for the ancient hardware that doesn't
+	 * support it.
+	 */
+	if (pgprot_val(pgprot) & _PAGE_PRESENT)
+		pgprot_val(pgprot) |= _PAGE_GLOBAL;
+	else
+		pgprot_val(pgprot) &= ~_PAGE_GLOBAL;
 
-		/* deal with the NX bit */
-		if (!(pgprot_val(pgprot) & _PAGE_NX))
-			cpa->pfn &= ~_PAGE_NX;
+	pgprot = canon_pgprot(pgprot);
 
-		set_pte(pte, pfn_pte(cpa->pfn >> PAGE_SHIFT, pgprot));
+	while (num_pages-- && start < end) {
+		set_pte(pte, pfn_pte(cpa->pfn, pgprot));
 
 		start	 += PAGE_SIZE;
-		cpa->pfn += PAGE_SIZE;
+		cpa->pfn++;
 		pte++;
 	}
 }

@@ -974,11 +983,11 @@ static int populate_pmd(struct cpa_data *cpa,
 
 		pmd = pmd_offset(pud, start);
 
-		set_pmd(pmd, __pmd(cpa->pfn | _PAGE_PSE |
+		set_pmd(pmd, __pmd(cpa->pfn << PAGE_SHIFT | _PAGE_PSE |
 				   massage_pgprot(pmd_pgprot)));
 
 		start	  += PMD_SIZE;
-		cpa->pfn  += PMD_SIZE;
+		cpa->pfn  += PMD_SIZE >> PAGE_SHIFT;
 		cur_pages += PMD_SIZE >> PAGE_SHIFT;
 	}
 

@@ -1046,12 +1055,12 @@ static int populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
 	/*
 	 * Map everything starting from the Gb boundary, possibly with 1G pages
 	 */
-	while (end - start >= PUD_SIZE) {
-		set_pud(pud, __pud(cpa->pfn | _PAGE_PSE |
+	while (cpu_has_gbpages && end - start >= PUD_SIZE) {
+		set_pud(pud, __pud(cpa->pfn << PAGE_SHIFT | _PAGE_PSE |
 				   massage_pgprot(pud_pgprot)));
 
 		start	  += PUD_SIZE;
-		cpa->pfn  += PUD_SIZE;
+		cpa->pfn  += PUD_SIZE >> PAGE_SHIFT;
 		cur_pages += PUD_SIZE >> PAGE_SHIFT;
 		pud++;
 	}

@@ -1962,6 +1971,9 @@ int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
 	if (!(page_flags & _PAGE_NX))
 		cpa.mask_clr = __pgprot(_PAGE_NX);
 
+	if (!(page_flags & _PAGE_RW))
+		cpa.mask_clr = __pgprot(_PAGE_RW);
+
 	cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags);
 
 	retval = __change_page_attr_set_clr(&cpa, 0);

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index ed5b67338294..338402b91d2e 100644
@@ -38,6 +38,11 @@
  * say 0 - 3G.
  */
 
+int __init efi_alloc_page_tables(void)
+{
+	return 0;
+}
+
 void efi_sync_low_kernel_mappings(void) {}
 void __init efi_dump_pagetable(void) {}
 int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)

@@ -85,7 +90,7 @@ void __init efi_call_phys_epilog(pgd_t *save_pgd)
 	__flush_tlb_all();
 }
 
-void __init efi_runtime_mkexec(void)
+void __init efi_runtime_update_mappings(void)
 {
 	if (__supported_pte_mask & _PAGE_NX)
 		runtime_code_page_mkexec();

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index 2d66db8f80f9..2326bf51978f 100644
@@ -1,3 +1,5 @@
+#define pr_fmt(fmt) "efi: " fmt
+
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/string.h>

@@ -55,13 +57,41 @@ void efi_delete_dummy_variable(void)
 }
 
 /*
+ * In the nonblocking case we do not attempt to perform garbage
+ * collection if we do not have enough free space. Rather, we do the
+ * bare minimum check and give up immediately if the available space
+ * is below EFI_MIN_RESERVE.
+ *
+ * This function is intended to be small and simple because it is
+ * invoked from crash handler paths.
+ */
+static efi_status_t
+query_variable_store_nonblocking(u32 attributes, unsigned long size)
+{
+	efi_status_t status;
+	u64 storage_size, remaining_size, max_size;
+
+	status = efi.query_variable_info_nonblocking(attributes, &storage_size,
+						     &remaining_size,
+						     &max_size);
+	if (status != EFI_SUCCESS)
+		return status;
+
+	if (remaining_size - size < EFI_MIN_RESERVE)
+		return EFI_OUT_OF_RESOURCES;
+
+	return EFI_SUCCESS;
+}
+
+/*
  * Some firmware implementations refuse to boot if there's insufficient space
  * in the variable store. Ensure that we never use more than a safe limit.
  *
  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
  * store.
  */
-efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
+efi_status_t efi_query_variable_store(u32 attributes, unsigned long size,
+				      bool nonblocking)
 {
 	efi_status_t status;
 	u64 storage_size, remaining_size, max_size;

@@ -69,6 +99,9 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
 	if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
 		return 0;
 
+	if (nonblocking)
+		return query_variable_store_nonblocking(attributes, size);
+
 	status = efi.query_variable_info(attributes, &storage_size,
 					 &remaining_size, &max_size);
 	if (status != EFI_SUCCESS)

@@ -267,7 +300,7 @@ void __init efi_apply_memmap_quirks(void)
 	 * services.
 	 */
 	if (!efi_runtime_supported()) {
-		pr_info("efi: Setup done, disabling due to 32/64-bit mismatch\n");
+		pr_info("Setup done, disabling due to 32/64-bit mismatch\n");
 		efi_unmap_memmap();
 	}
 

index 9e15d571b53c..aa1f743152a2 100644
@@ -61,8 +61,8 @@ static int __init uefi_init(void)
 	char vendor[100] = "unknown";
 	int i, retval;
 
-	efi.systab = early_memremap(efi_system_table,
-				    sizeof(efi_system_table_t));
+	efi.systab = early_memremap_ro(efi_system_table,
+				       sizeof(efi_system_table_t));
 	if (efi.systab == NULL) {
 		pr_warn("Unable to map EFI system table.\n");
 		return -ENOMEM;

@@ -86,8 +86,8 @@ static int __init uefi_init(void)
 			efi.systab->hdr.revision & 0xffff);
 
 	/* Show what we know for posterity */
-	c16 = early_memremap(efi_to_phys(efi.systab->fw_vendor),
-			     sizeof(vendor) * sizeof(efi_char16_t));
+	c16 = early_memremap_ro(efi_to_phys(efi.systab->fw_vendor),
+				sizeof(vendor) * sizeof(efi_char16_t));
 	if (c16) {
 		for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i)
 			vendor[i] = c16[i];

@@ -100,8 +100,8 @@ static int __init uefi_init(void)
 		efi.systab->hdr.revision & 0xffff, vendor);
 
 	table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables;
-	config_tables = early_memremap(efi_to_phys(efi.systab->tables),
-				       table_size);
+	config_tables = early_memremap_ro(efi_to_phys(efi.systab->tables),
+					  table_size);
 	if (config_tables == NULL) {
 		pr_warn("Unable to map EFI config table array.\n");
 		retval = -ENOMEM;

@@ -185,7 +185,7 @@ void __init efi_init(void)
 	efi_system_table = params.system_table;
 
 	memmap.phys_map = params.mmap;
-	memmap.map = early_memremap(params.mmap, params.mmap_size);
+	memmap.map = early_memremap_ro(params.mmap, params.mmap_size);
 	if (memmap.map == NULL) {
 		/*
 		* If we are booting via UEFI, the UEFI memory map is the only

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index 10e6774ab2a2..b23a271c6ae5 100644
@@ -386,7 +386,7 @@ static const struct sysfs_ops efivar_attr_ops = {
 
 static void efivar_release(struct kobject *kobj)
 {
-	struct efivar_entry *var = container_of(kobj, struct efivar_entry, kobj);
+	struct efivar_entry *var = to_efivar_entry(kobj);
 	kfree(var);
 }
 

index 22c5285f7705..75feb3f5829b 100644
@@ -167,14 +167,11 @@ static struct kset *esrt_kset;
 static int esre_create_sysfs_entry(void *esre, int entry_num)
 {
 	struct esre_entry *entry;
-	char name[20];
 
 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 	if (!entry)
 		return -ENOMEM;
 
-	sprintf(name, "entry%d", entry_num);
-
 	entry->kobj.kset = esrt_kset;
 
 	if (esrt->fw_resource_version == 1) {

@@ -182,7 +179,7 @@ static int esre_create_sysfs_entry(void *esre, int entry_num)
 
 		entry->esre.esre1 = esre;
 		rc = kobject_init_and_add(&entry->kobj, &esre1_ktype, NULL,
-					  "%s", name);
+					  "entry%d", entry_num);
 		if (rc) {
 			kfree(entry);
 			return rc;

index 3397902e4040..6086a874fa3c 100644
@@ -190,6 +190,10 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
 
 	pr_efi(sys_table, "Booting Linux Kernel...\n");
 
+	status = check_platform_features(sys_table);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
 	/*
 	 * Get a handle to the loaded image protocol.  This is used to get
 	 * information about the running image, such as size and the command

index 495ebd657e38..6f42be4d0084 100644
@@ -9,6 +9,23 @@
 #include <linux/efi.h>
 #include <asm/efi.h>
 
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
+{
+	int block;
+
+	/* non-LPAE kernels can run anywhere */
+	if (!IS_ENABLED(CONFIG_ARM_LPAE))
+		return EFI_SUCCESS;
+
+	/* LPAE kernels need compatible hardware */
+	block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
+	if (block < 5) {
+		pr_efi_err(sys_table_arg, "This LPAE kernel is not supported by your CPU\n");
+		return EFI_UNSUPPORTED;
+	}
+	return EFI_SUCCESS;
+}
+
 efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
 				 unsigned long *image_addr,
 				 unsigned long *image_size,

index 78dfbd34b6bf..047fc343665a 100644
@@ -12,14 +12,34 @@
 #include <linux/efi.h>
 #include <asm/efi.h>
 #include <asm/sections.h>
+#include <asm/sysreg.h>
 
-efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table_arg,
-					unsigned long *image_addr,
-					unsigned long *image_size,
-					unsigned long *reserve_addr,
-					unsigned long *reserve_size,
-					unsigned long dram_base,
-					efi_loaded_image_t *image)
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
+{
+	u64 tg;
+
+	/* UEFI mandates support for 4 KB granularity, no need to check */
+	if (IS_ENABLED(CONFIG_ARM64_4K_PAGES))
+		return EFI_SUCCESS;
+
+	tg = (read_cpuid(ID_AA64MMFR0_EL1) >> ID_AA64MMFR0_TGRAN_SHIFT) & 0xf;
+	if (tg != ID_AA64MMFR0_TGRAN_SUPPORTED) {
+		if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
+			pr_efi_err(sys_table_arg, "This 64 KB granular kernel is not supported by your CPU\n");
+		else
+			pr_efi_err(sys_table_arg, "This 16 KB granular kernel is not supported by your CPU\n");
+		return EFI_UNSUPPORTED;
+	}
+	return EFI_SUCCESS;
+}
+
+efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg,
+				 unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 unsigned long dram_base,
+				 efi_loaded_image_t *image)
 {
 	efi_status_t status;
 	unsigned long kernel_size, kernel_memsize = 0;

index 6b6548fda089..981c6035ce09 100644
@@ -5,6 +5,16 @@
 /* error code which can't be mistaken for valid address */
 #define EFI_ERROR	(~0UL)
 
+/*
+ * __init annotations should not be used in the EFI stub, since the code is
+ * either included in the decompressor (x86, ARM) where they have no effect,
+ * or the whole stub is __init annotated at the section level (arm64), by
+ * renaming the sections, in which case the __init annotation will be
+ * redundant, and will result in section names like .init.init.text, and our
+ * linker script does not expect that.
+ */
+#undef __init
+
 void efi_char16_printk(efi_system_table_t *, efi_char16_t *);
 
 efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image,

@@ -43,4 +53,6 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
 		     unsigned long desc_size, efi_memory_desc_t *runtime_map,
 		     int *count);
 
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg);
+
 #endif

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index 7f2ea21c730d..0ac594c0a234 100644
@@ -300,7 +300,18 @@ check_var_size(u32 attributes, unsigned long size)
 	if (!fops->query_variable_store)
 		return EFI_UNSUPPORTED;
 
-	return fops->query_variable_store(attributes, size);
+	return fops->query_variable_store(attributes, size, false);
+}
+
+static efi_status_t
+check_var_size_nonblocking(u32 attributes, unsigned long size)
+{
+	const struct efivar_operations *fops = __efivars->ops;
+
+	if (!fops->query_variable_store)
+		return EFI_UNSUPPORTED;
+
+	return fops->query_variable_store(attributes, size, true);
 }
 
 static int efi_status_to_err(efi_status_t status)

@@ -681,7 +692,8 @@ efivar_entry_set_nonblocking(efi_char16_t *name, efi_guid_t vendor,
 	if (!spin_trylock_irqsave(&__efivars->lock, flags))
 		return -EBUSY;
 
-	status = check_var_size(attributes, size + ucs2_strsize(name, 1024));
+	status = check_var_size_nonblocking(attributes,
+					    size + ucs2_strsize(name, 1024));
 	if (status != EFI_SUCCESS) {
 		spin_unlock_irqrestore(&__efivars->lock, flags);
 		return -ENOSPC;

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