diff options
| author | Ashok Raj <ashok.raj@intel.com> | 2023-01-09 18:35:50 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-11 18:39:23 +0300 |
| commit | 89e848bb4aa140e701eb0d017736ce5d1ee198da (patch) | |
| tree | 4466e22652cc1bf24bc73ec075496bdb3f84bdb4 | |
| parent | f5e78fa916aafe2dbcb323ee8b436f3e81cf0aec (diff) | |
| download | linux-89e848bb4aa140e701eb0d017736ce5d1ee198da.tar.xz | |
x86/microcode: Add a parameter to microcode_check() to store CPU capabilities
[ Upstream commit ab31c74455c64e69342ddab21fd9426fcbfefde7 ]
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 <ashok.raj@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230109153555.4986-2-ashok.raj@intel.com
Stable-dep-of: c0dd9245aa9e ("x86/microcode: Check CPU capabilities after late microcode update correctly")
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | arch/x86/include/asm/processor.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 21 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/microcode/core.c | 3 |
3 files changed, 16 insertions, 10 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 01bcbf8a25b2..6d40c409ebc1 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -840,7 +840,7 @@ bool xen_set_default_idle(void); #endif void __noreturn stop_this_cpu(void *dummy); -void microcode_check(void); +void microcode_check(struct cpuinfo_x86 *prev_info); enum l1tf_mitigations { L1TF_MITIGATION_OFF, diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 95f52540db37..f724002adbfc 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -2130,30 +2130,35 @@ 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"); diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index 707a385943b4..2c70f3cfae68 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -509,13 +509,14 @@ wait_for_siblings: static int microcode_reload_late(void) { int old = boot_cpu_data.microcode, ret; + struct cpuinfo_x86 prev_info; atomic_set(&late_cpus_in, 0); atomic_set(&late_cpus_out, 0); ret = stop_machine_cpuslocked(__reload_late, NULL, cpu_online_mask); if (ret == 0) - microcode_check(); + microcode_check(&prev_info); pr_info("Reload completed, microcode revision: 0x%x -> 0x%x\n", old, boot_cpu_data.microcode); |