diff options
Diffstat (limited to 'arch/x86/kernel/cpu/microcode/amd.c')
| -rw-r--r-- | arch/x86/kernel/cpu/microcode/amd.c | 38 |
1 files changed, 33 insertions, 5 deletions
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index 2d630138bf3e..da922d1e2f71 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -178,6 +178,16 @@ static unsigned int verify_patch_size(u8 family, u32 patch_size, } /* + * Those patch levels cannot be updated to newer ones and thus should be final. + */ +static u32 final_levels[] = { + 0x01000098, + 0x0100009f, + 0x010000af, + 0, /* T-101 terminator */ +}; + +/* * Check the current patch level on this CPU. * * @rev: Use it to return the patch level. It is set to 0 in the case of @@ -187,13 +197,31 @@ static unsigned int verify_patch_size(u8 family, u32 patch_size, * - true: if update should stop * - false: otherwise */ -bool check_current_patch_level(u32 *rev) +bool check_current_patch_level(u32 *rev, bool early) { - u32 dummy; + u32 lvl, dummy, i; + bool ret = false; + u32 *levels; + + native_rdmsr(MSR_AMD64_PATCH_LEVEL, lvl, dummy); + + if (IS_ENABLED(CONFIG_X86_32) && early) + levels = (u32 *)__pa_nodebug(&final_levels); + else + levels = final_levels; + + for (i = 0; levels[i]; i++) { + if (lvl == levels[i]) { + lvl = 0; + ret = true; + break; + } + } - native_rdmsr(MSR_AMD64_PATCH_LEVEL, *rev, dummy); + if (rev) + *rev = lvl; - return false; + return ret; } int __apply_microcode_amd(struct microcode_amd *mc_amd) @@ -229,7 +257,7 @@ int apply_microcode_amd(int cpu) mc_amd = p->data; uci->mc = p->data; - if (check_current_patch_level(&rev)) + if (check_current_patch_level(&rev, false)) return -1; /* need to apply patch? */ |