diff options
| -rw-r--r-- | arch/x86/include/asm/efi.h | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/ibt.h | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/apm_32.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 5 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi_64.c | 5 |
5 files changed, 15 insertions, 7 deletions
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index cd19b9eca3f6..9f8ded3de038 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -106,6 +106,8 @@ static inline void efi_fpu_end(void) extern asmlinkage u64 __efi_call(void *fp, ...); +extern bool efi_disable_ibt_for_runtime; + #define efi_call(...) ({ \ __efi_nargs_check(efi_call, 7, __VA_ARGS__); \ __efi_call(__VA_ARGS__); \ @@ -121,7 +123,7 @@ extern asmlinkage u64 __efi_call(void *fp, ...); #undef arch_efi_call_virt #define arch_efi_call_virt(p, f, args...) ({ \ - u64 ret, ibt = ibt_save(); \ + u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime); \ ret = efi_call((void *)p->f, args); \ ibt_restore(ibt); \ ret; \ diff --git a/arch/x86/include/asm/ibt.h b/arch/x86/include/asm/ibt.h index 9b08082a5d9f..baae6b4fea23 100644 --- a/arch/x86/include/asm/ibt.h +++ b/arch/x86/include/asm/ibt.h @@ -74,7 +74,7 @@ static inline bool is_endbr(u32 val) return val == gen_endbr(); } -extern __noendbr u64 ibt_save(void); +extern __noendbr u64 ibt_save(bool disable); extern __noendbr void ibt_restore(u64 save); #else /* __ASSEMBLY__ */ @@ -100,7 +100,7 @@ extern __noendbr void ibt_restore(u64 save); static inline bool is_endbr(u32 val) { return false; } -static inline u64 ibt_save(void) { return 0; } +static inline u64 ibt_save(bool disable) { return 0; } static inline void ibt_restore(u64 save) { } #else /* __ASSEMBLY__ */ diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c index 60e330cdbd17..c6c15ce1952f 100644 --- a/arch/x86/kernel/apm_32.c +++ b/arch/x86/kernel/apm_32.c @@ -609,7 +609,7 @@ static long __apm_bios_call(void *_call) apm_irq_save(flags); firmware_restrict_branch_speculation_start(); - ibt = ibt_save(); + ibt = ibt_save(true); APM_DO_SAVE_SEGS; apm_bios_call_asm(call->func, call->ebx, call->ecx, &call->eax, &call->ebx, &call->ecx, &call->edx, @@ -690,7 +690,7 @@ static long __apm_bios_call_simple(void *_call) apm_irq_save(flags); firmware_restrict_branch_speculation_start(); - ibt = ibt_save(); + ibt = ibt_save(true); APM_DO_SAVE_SEGS; error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx, &call->eax); diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 9cfca3d7d0e2..54b246414eeb 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -571,13 +571,14 @@ __setup("nopku", setup_disable_pku); #ifdef CONFIG_X86_KERNEL_IBT -__noendbr u64 ibt_save(void) +__noendbr u64 ibt_save(bool disable) { u64 msr = 0; if (cpu_feature_enabled(X86_FEATURE_IBT)) { rdmsrl(MSR_IA32_S_CET, msr); - wrmsrl(MSR_IA32_S_CET, msr & ~CET_ENDBR_EN); + if (disable) + wrmsrl(MSR_IA32_S_CET, msr & ~CET_ENDBR_EN); } return msr; diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 2e6fe430cb07..232acf418cfb 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -389,11 +389,15 @@ static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf) return err1 || err2; } +bool efi_disable_ibt_for_runtime __ro_after_init = true; + static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *md, bool has_ibt) { unsigned long pf = 0; + efi_disable_ibt_for_runtime |= !has_ibt; + if (md->attribute & EFI_MEMORY_XP) pf |= _PAGE_NX; @@ -415,6 +419,7 @@ void __init efi_runtime_update_mappings(void) * exists, since it is intended to supersede EFI_PROPERTIES_TABLE. */ if (efi_enabled(EFI_MEM_ATTR)) { + efi_disable_ibt_for_runtime = false; efi_memattr_apply_permissions(NULL, efi_update_mem_attr); return; } |