diff options
Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
| -rw-r--r-- | arch/x86/kernel/cpu/amd.c | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index a5ece6ebe8a7..5398db4dedb4 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -546,6 +546,23 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c) u64 msr; /* + * Mark using WBINVD is needed during kexec on processors that + * support SME. This provides support for performing a successful + * kexec when going from SME inactive to SME active (or vice-versa). + * + * The cache must be cleared so that if there are entries with the + * same physical address, both with and without the encryption bit, + * they don't race each other when flushed and potentially end up + * with the wrong entry being committed to memory. + * + * Test the CPUID bit directly because with mem_encrypt=off the + * BSP will clear the X86_FEATURE_SME bit and the APs will not + * see it set after that. + */ + if (c->extended_cpuid_level >= 0x8000001f && (cpuid_eax(0x8000001f) & BIT(0))) + __this_cpu_write(cache_state_incoherent, true); + + /* * BIOS support is required for SME and SEV. * For SME: If BIOS has enabled SME then adjust x86_phys_bits by * the SME physical address space reduction value. @@ -1326,8 +1343,8 @@ static const char * const s5_reset_reason_txt[] = { static __init int print_s5_reset_status_mmio(void) { - unsigned long value; void __iomem *addr; + u32 value; int i; if (!cpu_feature_enabled(X86_FEATURE_ZEN)) @@ -1340,12 +1357,16 @@ static __init int print_s5_reset_status_mmio(void) value = ioread32(addr); iounmap(addr); + /* Value with "all bits set" is an error response and should be ignored. */ + if (value == U32_MAX) + return 0; + for (i = 0; i < ARRAY_SIZE(s5_reset_reason_txt); i++) { if (!(value & BIT(i))) continue; if (s5_reset_reason_txt[i]) { - pr_info("x86/amd: Previous system reset reason [0x%08lx]: %s\n", + pr_info("x86/amd: Previous system reset reason [0x%08x]: %s\n", value, s5_reset_reason_txt[i]); } } |