From 27d7b085f2f568050d638b694ed2f51495db718c Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 17 Feb 2020 16:23:15 +0000 Subject: [PATCH 5/9] target/i386: check for availability of MSR_IA32_UCODE_REV as an emulated MSR MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Paolo Bonzini Message-id: <20200217162316.2464-6-pbonzini@redhat.com> Patchwork-id: 93898 O-Subject: [RHEL-AV-8.2.0 qemu-kvm PATCH 5/6] target/i386: check for availability of MSR_IA32_UCODE_REV as an emulated MSR Bugzilla: 1791648 RH-Acked-by: Philippe Mathieu-Daudé RH-Acked-by: Maxim Levitsky RH-Acked-by: Dr. David Alan Gilbert Even though MSR_IA32_UCODE_REV has been available long before Linux 5.6, which added it to the emulated MSR list, a bug caused the microcode version to revert to 0x100000000 on INIT. As a result, processors other than the bootstrap processor would not see the host microcode revision; some Windows version complain loudly about this and crash with a fairly explicit MICROCODE REVISION MISMATCH error. [If running 5.6 prereleases, the kernel fix "KVM: x86: do not reset microcode version on INIT or RESET" should also be applied.] Reported-by: Alex Williamson Message-id: <20200211175516.10716-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini (cherry picked from commit 6702514814c7e7b4cbf179624539b5f38c72740b) Signed-off-by: Danilo C. L. de Paula --- target/i386/kvm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/target/i386/kvm.c b/target/i386/kvm.c index 6c61aef..99840ca 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -105,6 +105,7 @@ static bool has_msr_smi_count; static bool has_msr_arch_capabs; static bool has_msr_core_capabs; static bool has_msr_vmx_vmfunc; +static bool has_msr_ucode_rev; static uint32_t has_architectural_pmu_version; static uint32_t num_architectural_pmu_gp_counters; @@ -2056,6 +2057,9 @@ static int kvm_get_supported_msrs(KVMState *s) case MSR_IA32_VMX_VMFUNC: has_msr_vmx_vmfunc = true; break; + case MSR_IA32_UCODE_REV: + has_msr_ucode_rev = true; + break; } } } @@ -2696,8 +2700,7 @@ static void kvm_init_msrs(X86CPU *cpu) env->features[FEAT_CORE_CAPABILITY]); } - if (kvm_arch_get_supported_msr_feature(kvm_state, - MSR_IA32_UCODE_REV)) { + if (has_msr_ucode_rev) { kvm_msr_entry_add(cpu, MSR_IA32_UCODE_REV, cpu->ucode_rev); } -- 1.8.3.1