From 0f42b790c9ba5ec2f25b7da8b0b6d361082d67b0 Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Mon, 4 Feb 2019 14:23:29 -0800 Subject: x86/cpufeature: Add facility to check for min microcode revisions For bug workarounds or checks, it is useful to check for specific microcode revisions. Add a new generic function to match the CPU with stepping. Add the other function to check the min microcode revisions for the matched CPU. A new table format is introduced to facilitate the quirk to fill the related information. This does not change the existing x86_cpu_id because it's an ABI shared with modules, and also has quite different requirements, as in no wildcards, but everything has to be matched exactly. Originally-by: Andi Kleen Suggested-by: Thomas Gleixner Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Acked-by: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: eranian@google.com Link: https://lkml.kernel.org/r/1549319013-4522-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/cpu_device_id.h | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/cpu_device_id.h b/arch/x86/include/asm/cpu_device_id.h index baeba05671268..3417110574c12 100644 --- a/arch/x86/include/asm/cpu_device_id.h +++ b/arch/x86/include/asm/cpu_device_id.h @@ -11,4 +11,32 @@ extern const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match); +/* + * Match specific microcode revisions. + * + * vendor/family/model/stepping must be all set. + * + * Only checks against the boot CPU. When mixed-stepping configs are + * valid for a CPU model, add a quirk for every valid stepping and + * do the fine-tuning in the quirk handler. + */ + +struct x86_cpu_desc { + __u8 x86_family; + __u8 x86_vendor; + __u8 x86_model; + __u8 x86_stepping; + __u32 x86_microcode_rev; +}; + +#define INTEL_CPU_DESC(mod, step, rev) { \ + .x86_family = 6, \ + .x86_vendor = X86_VENDOR_INTEL, \ + .x86_model = mod, \ + .x86_stepping = step, \ + .x86_microcode_rev = rev, \ +} + +extern bool x86_cpu_has_min_microcode_rev(const struct x86_cpu_desc *table); + #endif -- cgit v1.2.3