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

Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Drop the unused EFI_SYSTEM_TABLES efi.flags bit and ensure the
     ARM/arm64 EFI System Table mapping is read-only (Ard Biesheuvel)

   - Add a comment to explain that one of the code paths in the x86/pat
     code is only executed for EFI boot (Matt Fleming)

   - Improve Secure Boot status checks on arm64 and handle unexpected
     errors (Linn Crosetto)

   - Remove the global EFI memory map variable 'memmap' as the same
     information is already available in efi::memmap (Matt Fleming)

   - Add EFI Memory Attribute table support for ARM/arm64 (Ard
     Biesheuvel)

   - Add EFI GOP framebuffer support for ARM/arm64 (Ard Biesheuvel)

   - Add EFI Bootloader Control driver for storing reboot(2) data in EFI
     variables for consumption by bootloaders (Jeremy Compostella)

   - Add Core EFI capsule support (Matt Fleming)

   - Add EFI capsule char driver (Kweh, Hock Leong)

   - Unify EFI memory map code for ARM and arm64 (Ard Biesheuvel)

   - Add generic EFI support for detecting when firmware corrupts CPU
     status register bits (like IRQ flags) when performing EFI runtime
     service calls (Mark Rutland)

  ... and other misc cleanups"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  efivarfs: Make efivarfs_file_ioctl() static
  efi: Merge boolean flag arguments
  efi/capsule: Move 'capsule' to the stack in efi_capsule_supported()
  efibc: Fix excessive stack footprint warning
  efi/capsule: Make efi_capsule_pending() lockless
  efi: Remove unnecessary (and buggy) .memmap initialization from the Xen EFI driver
  efi/runtime-wrappers: Remove ARCH_EFI_IRQ_FLAGS_MASK #ifdef
  x86/efi: Enable runtime call flag checking
  arm/efi: Enable runtime call flag checking
  arm64/efi: Enable runtime call flag checking
  efi/runtime-wrappers: Detect firmware IRQ flag corruption
  efi/runtime-wrappers: Remove redundant #ifdefs
  x86/efi: Move to generic {__,}efi_call_virt()
  arm/efi: Move to generic {__,}efi_call_virt()
  arm64/efi: Move to generic {__,}efi_call_virt()
  efi/runtime-wrappers: Add {__,}efi_call_virt() templates
  efi/arm-init: Reserve rather than unmap the memory map for ARM as well
  efi: Add misc char driver interface to update EFI firmware
  x86/efi: Force EFI reboot to process pending capsules
  efi: Add 'capsule' update support
  ...

3 files changed, 66 insertions, 29 deletions

diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
index 8e88a696c9cb..622db3c6474e 100644
--- a/arch/arm64/include/asm/efi.h
+++ b/arch/arm64/include/asm/efi.h
@@ -4,6 +4,7 @@
 #include <asm/io.h>
 #include <asm/mmu_context.h>
 #include <asm/neon.h>
+#include <asm/ptrace.h>
 #include <asm/tlbflush.h>
 
 #ifdef CONFIG_EFI
@@ -14,32 +15,29 @@ extern void efi_init(void);
 
 int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
 
-#define efi_call_virt(f, ...)						\
+#define efi_set_mapping_permissions	efi_create_mapping
+
+#define arch_efi_call_virt_setup()					\
 ({									\
-	efi_##f##_t *__f;						\
-	efi_status_t __s;						\
-									\
 	kernel_neon_begin();						\
 	efi_virtmap_load();						\
-	__f = efi.systab->runtime->f;					\
-	__s = __f(__VA_ARGS__);						\
-	efi_virtmap_unload();						\
-	kernel_neon_end();						\
-	__s;								\
 })
 
-#define __efi_call_virt(f, ...)						\
+#define arch_efi_call_virt(f, args...)					\
 ({									\
 	efi_##f##_t *__f;						\
-									\
-	kernel_neon_begin();						\
-	efi_virtmap_load();						\
 	__f = efi.systab->runtime->f;					\
-	__f(__VA_ARGS__);						\
+	__f(args);							\
+})
+
+#define arch_efi_call_virt_teardown()					\
+({									\
 	efi_virtmap_unload();						\
 	kernel_neon_end();						\
 })
 
+#define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT)
+
 /* arch specific definitions used by the stub code */
 
 /*
@@ -50,7 +48,16 @@ int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
 #define EFI_FDT_ALIGN	SZ_2M   /* used by allocate_new_fdt_and_exit_boot() */
 #define MAX_FDT_OFFSET	SZ_512M
 
-#define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__)
+#define efi_call_early(f, ...)		sys_table_arg->boottime->f(__VA_ARGS__)
+#define __efi_call_early(f, ...)	f(__VA_ARGS__)
+#define efi_is_64bit()			(true)
+
+#define alloc_screen_info(x...)		&screen_info
+#define free_screen_info(x...)
+
+static inline void efifb_setup_from_dmi(struct screen_info *si, const char *opt)
+{
+}
 
 #define EFI_ALLOC_ALIGN		SZ_64K
 
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index b6abc852f2a1..78f52488f9ff 100644
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -17,22 +17,51 @@
 
 #include <asm/efi.h>
 
-int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
+/*
+ * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
+ * executable, everything else can be mapped with the XN bits
+ * set. Also take the new (optional) RO/XP bits into account.
+ */
+static __init pteval_t create_mapping_protection(efi_memory_desc_t *md)
 {
-	pteval_t prot_val;
+	u64 attr = md->attribute;
+	u32 type = md->type;
 
-	/*
-	 * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
-	 * executable, everything else can be mapped with the XN bits
-	 * set.
-	 */
-	if ((md->attribute & EFI_MEMORY_WB) == 0)
-		prot_val = PROT_DEVICE_nGnRE;
-	else if (md->type == EFI_RUNTIME_SERVICES_CODE ||
-		 !PAGE_ALIGNED(md->phys_addr))
-		prot_val = pgprot_val(PAGE_KERNEL_EXEC);
-	else
-		prot_val = pgprot_val(PAGE_KERNEL);
+	if (type == EFI_MEMORY_MAPPED_IO)
+		return PROT_DEVICE_nGnRE;
+
+	if (WARN_ONCE(!PAGE_ALIGNED(md->phys_addr),
+		      "UEFI Runtime regions are not aligned to 64 KB -- buggy firmware?"))
+		/*
+		 * If the region is not aligned to the page size of the OS, we
+		 * can not use strict permissions, since that would also affect
+		 * the mapping attributes of the adjacent regions.
+		 */
+		return pgprot_val(PAGE_KERNEL_EXEC);
+
+	/* R-- */
+	if ((attr & (EFI_MEMORY_XP | EFI_MEMORY_RO)) ==
+	    (EFI_MEMORY_XP | EFI_MEMORY_RO))
+		return pgprot_val(PAGE_KERNEL_RO);
+
+	/* R-X */
+	if (attr & EFI_MEMORY_RO)
+		return pgprot_val(PAGE_KERNEL_ROX);
+
+	/* RW- */
+	if (attr & EFI_MEMORY_XP || type != EFI_RUNTIME_SERVICES_CODE)
+		return pgprot_val(PAGE_KERNEL);
+
+	/* RWX */
+	return pgprot_val(PAGE_KERNEL_EXEC);
+}
+
+/* we will fill this structure from the stub, so don't put it in .bss */
+struct screen_info screen_info __section(.data);
+
+int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
+{
+	pteval_t prot_val = create_mapping_protection(md);
 
 	create_pgd_mapping(mm, md->phys_addr, md->virt_addr,
 			   md->num_pages << EFI_PAGE_SHIFT,
diff --git a/arch/arm64/kernel/image.h b/arch/arm64/kernel/image.h
index 5e360ce88f10..1428849aece8 100644
--- a/arch/arm64/kernel/image.h
+++ b/arch/arm64/kernel/image.h
@@ -112,6 +112,7 @@ __efistub___memset		= KALLSYMS_HIDE(__pi_memset);
 __efistub__text			= KALLSYMS_HIDE(_text);
 __efistub__end			= KALLSYMS_HIDE(_end);
 __efistub__edata		= KALLSYMS_HIDE(_edata);
+__efistub_screen_info		= KALLSYMS_HIDE(screen_info);
 
 #endif