diff options
Diffstat (limited to 'arch/x86/include/asm/nospec-branch.h')
| -rw-r--r-- | arch/x86/include/asm/nospec-branch.h | 49 |
1 files changed, 29 insertions, 20 deletions
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index aee26bb8230f..20d754b98f3f 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -12,7 +12,6 @@ #include <asm/msr-index.h> #include <asm/unwind_hints.h> #include <asm/percpu.h> -#include <asm/current.h> /* * Call depth tracking for Intel SKL CPUs to address the RSB underflow @@ -78,21 +77,21 @@ #include <asm/asm-offsets.h> #define CREDIT_CALL_DEPTH \ - movq $-1, PER_CPU_VAR(pcpu_hot + X86_call_depth); + movq $-1, PER_CPU_VAR(__x86_call_depth); #define RESET_CALL_DEPTH \ xor %eax, %eax; \ bts $63, %rax; \ - movq %rax, PER_CPU_VAR(pcpu_hot + X86_call_depth); + movq %rax, PER_CPU_VAR(__x86_call_depth); #define RESET_CALL_DEPTH_FROM_CALL \ movb $0xfc, %al; \ shl $56, %rax; \ - movq %rax, PER_CPU_VAR(pcpu_hot + X86_call_depth); \ + movq %rax, PER_CPU_VAR(__x86_call_depth); \ CALL_THUNKS_DEBUG_INC_CALLS #define INCREMENT_CALL_DEPTH \ - sarq $5, PER_CPU_VAR(pcpu_hot + X86_call_depth); \ + sarq $5, PER_CPU_VAR(__x86_call_depth); \ CALL_THUNKS_DEBUG_INC_CALLS #else @@ -177,7 +176,7 @@ add $(BITS_PER_LONG/8), %_ASM_SP; \ lfence; -#ifdef __ASSEMBLY__ +#ifdef __ASSEMBLER__ /* * (ab)use RETPOLINE_SAFE on RET to annotate away 'bare' RET instructions @@ -270,7 +269,7 @@ * typically has NO_MELTDOWN). * * While retbleed_untrain_ret() doesn't clobber anything but requires stack, - * entry_ibpb() will clobber AX, CX, DX. + * write_ibpb() will clobber AX, CX, DX. * * As such, this must be placed after every *SWITCH_TO_KERNEL_CR3 at a point * where we have a stack but before any RET instruction. @@ -280,7 +279,7 @@ VALIDATE_UNRET_END CALL_UNTRAIN_RET ALTERNATIVE_2 "", \ - "call entry_ibpb", \ibpb_feature, \ + "call write_ibpb", \ibpb_feature, \ __stringify(\call_depth_insns), X86_FEATURE_CALL_DEPTH #endif .endm @@ -328,19 +327,23 @@ .endm .macro CLEAR_BRANCH_HISTORY_VMEXIT - ALTERNATIVE "", "call clear_bhb_loop", X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT + ALTERNATIVE "", "call clear_bhb_loop", X86_FEATURE_CLEAR_BHB_VMEXIT .endm #else #define CLEAR_BRANCH_HISTORY #define CLEAR_BRANCH_HISTORY_VMEXIT #endif -#else /* __ASSEMBLY__ */ +#else /* __ASSEMBLER__ */ + +#define ITS_THUNK_SIZE 64 typedef u8 retpoline_thunk_t[RETPOLINE_THUNK_SIZE]; +typedef u8 its_thunk_t[ITS_THUNK_SIZE]; extern retpoline_thunk_t __x86_indirect_thunk_array[]; extern retpoline_thunk_t __x86_indirect_call_thunk_array[]; extern retpoline_thunk_t __x86_indirect_jump_thunk_array[]; +extern its_thunk_t __x86_indirect_its_thunk_array[]; #ifdef CONFIG_MITIGATION_RETHUNK extern void __x86_return_thunk(void); @@ -364,12 +367,18 @@ static inline void srso_return_thunk(void) {} static inline void srso_alias_return_thunk(void) {} #endif +#ifdef CONFIG_MITIGATION_ITS +extern void its_return_thunk(void); +#else +static inline void its_return_thunk(void) {} +#endif + extern void retbleed_return_thunk(void); extern void srso_return_thunk(void); extern void srso_alias_return_thunk(void); extern void entry_untrain_ret(void); -extern void entry_ibpb(void); +extern void write_ibpb(void); #ifdef CONFIG_X86_64 extern void clear_bhb_loop(void); @@ -387,6 +396,8 @@ extern void call_depth_return_thunk(void); __stringify(INCREMENT_CALL_DEPTH), \ X86_FEATURE_CALL_DEPTH) +DECLARE_PER_CPU_CACHE_HOT(u64, __x86_call_depth); + #ifdef CONFIG_CALL_THUNKS_DEBUG DECLARE_PER_CPU(u64, __x86_call_count); DECLARE_PER_CPU(u64, __x86_ret_count); @@ -434,12 +445,8 @@ static inline void call_depth_return_thunk(void) {} * Inline asm uses the %V modifier which is only in newer GCC * which is ensured when CONFIG_MITIGATION_RETPOLINE is defined. */ -#ifdef CONFIG_MITIGATION_RETPOLINE #define CALL_NOSPEC __CS_PREFIX("%V[thunk_target]") \ "call __x86_indirect_thunk_%V[thunk_target]\n" -#else -#define CALL_NOSPEC "call *%[thunk_target]\n" -#endif # define THUNK_TARGET(addr) [thunk_target] "r" (addr) @@ -517,11 +524,11 @@ void alternative_msr_write(unsigned int msr, u64 val, unsigned int feature) : "memory"); } -extern u64 x86_pred_cmd; - static inline void indirect_branch_prediction_barrier(void) { - alternative_msr_write(MSR_IA32_PRED_CMD, x86_pred_cmd, X86_FEATURE_USE_IBPB); + asm_inline volatile(ALTERNATIVE("", "call write_ibpb", X86_FEATURE_IBPB) + : ASM_CALL_CONSTRAINT + :: "rax", "rcx", "rdx", "memory"); } /* The Intel SPEC CTRL MSR base value cache */ @@ -558,11 +565,13 @@ DECLARE_STATIC_KEY_FALSE(switch_to_cond_stibp); DECLARE_STATIC_KEY_FALSE(switch_mm_cond_ibpb); DECLARE_STATIC_KEY_FALSE(switch_mm_always_ibpb); +DECLARE_STATIC_KEY_FALSE(switch_vcpu_ibpb); + DECLARE_STATIC_KEY_FALSE(mds_idle_clear); DECLARE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush); -DECLARE_STATIC_KEY_FALSE(mmio_stale_data_clear); +DECLARE_STATIC_KEY_FALSE(cpu_buf_vm_clear); extern u16 mds_verw_sel; @@ -602,6 +611,6 @@ static __always_inline void mds_idle_clear_cpu_buffers(void) mds_clear_cpu_buffers(); } -#endif /* __ASSEMBLY__ */ +#endif /* __ASSEMBLER__ */ #endif /* _ASM_X86_NOSPEC_BRANCH_H_ */ |