From 762f169f5d9b92f057ad2c27ec4e3849b743239a Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 7 Aug 2023 18:21:20 +0200 Subject: efi/x86: Move EFI runtime call setup/teardown helpers out of line Only the arch_efi_call_virt() macro that some architectures override needs to be a macro, given that it is variadic and encapsulates calls via function pointers that have different prototypes. The associated setup and teardown code are not special in this regard, and don't need to be instantiated at each call site. So turn them into ordinary C functions and move them out of line. Signed-off-by: Ard Biesheuvel --- arch/x86/include/asm/efi.h | 32 ++------------------------------ arch/x86/platform/efi/efi_32.c | 12 ++++++++++++ arch/x86/platform/efi/efi_64.c | 19 +++++++++++++++++-- 3 files changed, 31 insertions(+), 32 deletions(-) (limited to 'arch') diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index b0994ae3bc23..c4555b269a1b 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -91,19 +91,6 @@ static inline void efi_fpu_end(void) #ifdef CONFIG_X86_32 #define EFI_X86_KERNEL_ALLOC_LIMIT (SZ_512M - 1) - -#define arch_efi_call_virt_setup() \ -({ \ - efi_fpu_begin(); \ - firmware_restrict_branch_speculation_start(); \ -}) - -#define arch_efi_call_virt_teardown() \ -({ \ - firmware_restrict_branch_speculation_end(); \ - efi_fpu_end(); \ -}) - #else /* !CONFIG_X86_32 */ #define EFI_X86_KERNEL_ALLOC_LIMIT EFI_ALLOC_LIMIT @@ -116,14 +103,6 @@ extern bool efi_disable_ibt_for_runtime; __efi_call(__VA_ARGS__); \ }) -#define arch_efi_call_virt_setup() \ -({ \ - efi_sync_low_kernel_mappings(); \ - efi_fpu_begin(); \ - firmware_restrict_branch_speculation_start(); \ - efi_enter_mm(); \ -}) - #undef arch_efi_call_virt #define arch_efi_call_virt(p, f, args...) ({ \ u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime); \ @@ -132,13 +111,6 @@ extern bool efi_disable_ibt_for_runtime; ret; \ }) -#define arch_efi_call_virt_teardown() \ -({ \ - efi_leave_mm(); \ - firmware_restrict_branch_speculation_end(); \ - efi_fpu_end(); \ -}) - #ifdef CONFIG_KASAN /* * CONFIG_KASAN may redefine memset to __memset. __memset function is present @@ -168,8 +140,8 @@ extern void efi_delete_dummy_variable(void); extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr); extern void efi_free_boot_services(void); -void efi_enter_mm(void); -void efi_leave_mm(void); +void arch_efi_call_virt_setup(void); +void arch_efi_call_virt_teardown(void); /* kexec external ABI */ struct efi_setup_data { diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c index e06a199423c0..b2cc7b4552a1 100644 --- a/arch/x86/platform/efi/efi_32.c +++ b/arch/x86/platform/efi/efi_32.c @@ -140,3 +140,15 @@ void __init efi_runtime_update_mappings(void) } } } + +void arch_efi_call_virt_setup(void) +{ + efi_fpu_begin(); + firmware_restrict_branch_speculation_start(); +} + +void arch_efi_call_virt_teardown(void) +{ + firmware_restrict_branch_speculation_end(); + efi_fpu_end(); +} diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 77f7ac3668cb..91d31ac422d6 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -474,19 +474,34 @@ void __init efi_dump_pagetable(void) * can not change under us. * It should be ensured that there are no concurrent calls to this function. */ -void efi_enter_mm(void) +static void efi_enter_mm(void) { efi_prev_mm = current->active_mm; current->active_mm = &efi_mm; switch_mm(efi_prev_mm, &efi_mm, NULL); } -void efi_leave_mm(void) +static void efi_leave_mm(void) { current->active_mm = efi_prev_mm; switch_mm(&efi_mm, efi_prev_mm, NULL); } +void arch_efi_call_virt_setup(void) +{ + efi_sync_low_kernel_mappings(); + efi_fpu_begin(); + firmware_restrict_branch_speculation_start(); + efi_enter_mm(); +} + +void arch_efi_call_virt_teardown(void) +{ + efi_leave_mm(); + firmware_restrict_branch_speculation_end(); + efi_fpu_end(); +} + static DEFINE_SPINLOCK(efi_runtime_lock); /* -- cgit v1.2.3-70-g09d2 From aba7e066c738d4b349413a271b2a236aa55bacbc Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 2 Aug 2023 17:17:04 +0200 Subject: efi/x86: Ensure that EFI_RUNTIME_MAP is enabled for kexec CONFIG_EFI_RUNTIME_MAP needs to be enabled in order for kexec to be able to provide the required information about the EFI runtime mappings to the incoming kernel, regardless of whether kexec_load() or kexec_file_load() is being used. Without this information, kexec boot in EFI mode is not possible. The CONFIG_EFI_RUNTIME_MAP option is currently directly configurable if CONFIG_EXPERT is enabled, so that it can be turned on for debugging purposes even if KEXEC is not enabled. However, the upshot of this is that it can also be disabled even when it shouldn't. So tweak the Kconfig declarations to avoid this situation. Reported-by: Kirill A. Shutemov Signed-off-by: Ard Biesheuvel --- arch/x86/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 982b777eadc7..66bfabae8814 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1945,6 +1945,7 @@ config EFI select UCS2_STRING select EFI_RUNTIME_WRAPPERS select ARCH_USE_MEMREMAP_PROT + select EFI_RUNTIME_MAP if KEXEC_CORE help This enables the kernel to use EFI runtime services that are available (such as the EFI variable services). @@ -2020,7 +2021,6 @@ config EFI_MAX_FAKE_MEM config EFI_RUNTIME_MAP bool "Export EFI runtime maps to sysfs" if EXPERT depends on EFI - default KEXEC_CORE help Export EFI runtime memory regions to /sys/firmware/efi/runtime-map. That memory map is required by the 2nd kernel to set up EFI virtual -- cgit v1.2.3-70-g09d2