From ab31c74455c64e69342ddab21fd9426fcbfefde7 Mon Sep 17 00:00:00 2001 From: Ashok Raj Date: Mon, 9 Jan 2023 07:35:50 -0800 Subject: x86/microcode: Add a parameter to microcode_check() to store CPU capabilities Add a parameter to store CPU capabilities before performing a microcode update so that CPU capabilities can be compared before and after update. [ bp: Massage. ] Signed-off-by: Ashok Raj Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/20230109153555.4986-2-ashok.raj@intel.com --- arch/x86/kernel/cpu/common.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'arch/x86/kernel/cpu/common.c') diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 9cfca3d7d0e2..0f5a173d0871 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -2297,30 +2297,35 @@ void cpu_init_secondary(void) #endif #ifdef CONFIG_MICROCODE_LATE_LOADING -/* +/** + * microcode_check() - Check if any CPU capabilities changed after an update. + * @prev_info: CPU capabilities stored before an update. + * * The microcode loader calls this upon late microcode load to recheck features, * only when microcode has been updated. Caller holds microcode_mutex and CPU * hotplug lock. + * + * Return: None */ -void microcode_check(void) +void microcode_check(struct cpuinfo_x86 *prev_info) { - struct cpuinfo_x86 info; - perf_check_microcode(); /* Reload CPUID max function as it might've changed. */ - info.cpuid_level = cpuid_eax(0); + prev_info->cpuid_level = cpuid_eax(0); /* * Copy all capability leafs to pick up the synthetic ones so that * memcmp() below doesn't fail on that. The ones coming from CPUID will * get overwritten in get_cpu_cap(). */ - memcpy(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability)); + memcpy(&prev_info->x86_capability, &boot_cpu_data.x86_capability, + sizeof(prev_info->x86_capability)); - get_cpu_cap(&info); + get_cpu_cap(prev_info); - if (!memcmp(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability))) + if (!memcmp(&prev_info->x86_capability, &boot_cpu_data.x86_capability, + sizeof(prev_info->x86_capability))) return; pr_warn("x86/CPU: CPU features have changed after loading microcode, but might not take effect.\n"); -- cgit v1.2.3