From: Rik van Riel <riel@xxxxxxxxxxx> In addition, the CPU advertises the maximum number of pages that can be shot down with one INVLPGB instruction in CPUID. Save that information for later use. [ bp: use cpu_has(), typos, massage. ] Signed-off-by: Rik van Riel <riel@xxxxxxxxxxx> Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Link: https://lore.kernel.org/r/20250226030129.530345-3-riel@xxxxxxxxxxx --- arch/x86/Kconfig.cpu | 4 ++++ arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/include/asm/disabled-features.h | 8 +++++++- arch/x86/include/asm/tlbflush.h | 3 +++ arch/x86/kernel/cpu/amd.c | 6 ++++++ 5 files changed, 21 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu index 2a7279d80460..25c55cc17c5e 100644 --- a/arch/x86/Kconfig.cpu +++ b/arch/x86/Kconfig.cpu @@ -401,6 +401,10 @@ menuconfig PROCESSOR_SELECT This lets you choose what x86 vendor support code your kernel will include. +config BROADCAST_TLB_FLUSH + def_bool y + depends on CPU_SUP_AMD && 64BIT + config CPU_SUP_INTEL default y bool "Support Intel processors" if PROCESSOR_SELECT diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 508c0dad116b..8770dc185fe9 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -338,6 +338,7 @@ #define X86_FEATURE_CLZERO (13*32+ 0) /* "clzero" CLZERO instruction */ #define X86_FEATURE_IRPERF (13*32+ 1) /* "irperf" Instructions Retired Count */ #define X86_FEATURE_XSAVEERPTR (13*32+ 2) /* "xsaveerptr" Always save/restore FP error pointers */ +#define X86_FEATURE_INVLPGB (13*32+ 3) /* INVLPGB and TLBSYNC instructions supported */ #define X86_FEATURE_RDPRU (13*32+ 4) /* "rdpru" Read processor register at user level */ #define X86_FEATURE_WBNOINVD (13*32+ 9) /* "wbnoinvd" WBNOINVD instruction */ #define X86_FEATURE_AMD_IBPB (13*32+12) /* Indirect Branch Prediction Barrier */ diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h index c492bdc97b05..625a89259968 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -129,6 +129,12 @@ #define DISABLE_SEV_SNP (1 << (X86_FEATURE_SEV_SNP & 31)) #endif +#ifdef CONFIG_X86_BROADCAST_TLB_FLUSH +#define DISABLE_INVLPGB 0 +#else +#define DISABLE_INVLPGB (1 << (X86_FEATURE_INVLPGB & 31)) +#endif + /* * Make sure to add features to the correct mask */ @@ -146,7 +152,7 @@ #define DISABLED_MASK11 (DISABLE_RETPOLINE|DISABLE_RETHUNK|DISABLE_UNRET| \ DISABLE_CALL_DEPTH_TRACKING|DISABLE_USER_SHSTK) #define DISABLED_MASK12 (DISABLE_FRED|DISABLE_LAM) -#define DISABLED_MASK13 0 +#define DISABLED_MASK13 (DISABLE_INVLPGB) #define DISABLED_MASK14 0 #define DISABLED_MASK15 0 #define DISABLED_MASK16 (DISABLE_PKU|DISABLE_OSPKE|DISABLE_LA57|DISABLE_UMIP| \ diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 3da645139748..855c13da2045 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -183,6 +183,9 @@ static inline void cr4_init_shadow(void) extern unsigned long mmu_cr4_features; extern u32 *trampoline_cr4_features; +/* How many pages can be invalidated with one INVLPGB. */ +extern u16 invlpgb_count_max; + extern void initialize_tlbstate_and_flush(void); /* diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 54194f5995de..7a72ef47a983 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -29,6 +29,8 @@ #include "cpu.h" +u16 invlpgb_count_max __ro_after_init; + static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p) { u32 gprs[8] = { 0 }; @@ -1139,6 +1141,10 @@ static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c) tlb_lli_2m[ENTRIES] = eax & mask; tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1; + + /* Max number of pages INVLPGB can invalidate in one shot */ + if (cpu_has(c, X86_FEATURE_INVLPGB)) + invlpgb_count_max = (cpuid_edx(0x80000008) & 0xffff) + 1; } static const struct cpu_dev amd_cpu_dev = { -- 2.43.0
