From 098416e6986127f7e4c8ce4fd6bbbd80e55b0386 Mon Sep 17 00:00:00 2001 From: Tony Luck Date: Tue, 10 Nov 2020 16:39:54 -0800 Subject: [PATCH] x86/mce: Use "safe" MSR functions when enabling additional error logging Booting as a guest under KVM results in error messages about unchecked MSR access: unchecked MSR access error: RDMSR from 0x17f at rIP: 0xffffffff84483f16 (mce_intel_feature_init+0x156/0x270) because KVM doesn't provide emulation for random model specific registers. Switch to using rdmsrl_safe()/wrmsrl_safe() to avoid the message. Fixes: 68299a42f842 ("x86/mce: Enable additional error logging on certain Intel CPUs") Reported-by: Qian Cai Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20201111003954.GA11878@agluck-desk2.amr.corp.intel.com --- arch/x86/kernel/cpu/mce/intel.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/mce/intel.c b/arch/x86/kernel/cpu/mce/intel.c index b47883e3..c2476fe 100644 --- a/arch/x86/kernel/cpu/mce/intel.c +++ b/arch/x86/kernel/cpu/mce/intel.c @@ -521,9 +521,10 @@ static void intel_imc_init(struct cpuinfo_x86 *c) case INTEL_FAM6_SANDYBRIDGE_X: case INTEL_FAM6_IVYBRIDGE_X: case INTEL_FAM6_HASWELL_X: - rdmsrl(MSR_ERROR_CONTROL, error_control); + if (rdmsrl_safe(MSR_ERROR_CONTROL, &error_control)) + return; error_control |= 2; - wrmsrl(MSR_ERROR_CONTROL, error_control); + wrmsrl_safe(MSR_ERROR_CONTROL, error_control); break; } } -- 2.7.4