From aec5e9c3a94cf8b7920f59bef69a6f426092c4a0 Mon Sep 17 00:00:00 2001 From: Bandan Das Date: Sun, 25 Nov 2018 23:17:28 -0500 Subject: [PATCH 1/2] kvm: Use KVM_GET_MSR_INDEX_LIST for MSR_IA32_ARCH_CAPABILITIES support When writing to guest's MSR_IA32_ARCH_CAPABILITIES, check whether it's supported in the guest using the KVM_GET_MSR_INDEX_LIST ioctl. Fixes: d86f963694df27f11b3681ffd225c9362de1b634 Suggested-by: Eduardo Habkost Tested-by: balducci@units.it Signed-off-by: Bandan Das Message-Id: Signed-off-by: Eduardo Habkost --- target/i386/kvm.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/target/i386/kvm.c b/target/i386/kvm.c index f524e7d929..3d6739a2b2 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -95,6 +95,7 @@ static bool has_msr_xss; static bool has_msr_spec_ctrl; static bool has_msr_virt_ssbd; static bool has_msr_smi_count; +static bool has_msr_arch_capabs; static uint32_t has_architectural_pmu_version; static uint32_t num_architectural_pmu_gp_counters; @@ -1481,6 +1482,9 @@ static int kvm_get_supported_msrs(KVMState *s) case MSR_VIRT_SSBD: has_msr_virt_ssbd = true; break; + case MSR_IA32_ARCH_CAPABILITIES: + has_msr_arch_capabs = true; + break; } } } @@ -2002,14 +2006,9 @@ static int kvm_put_msrs(X86CPU *cpu, int level) #endif /* If host supports feature MSR, write down. */ - if (kvm_feature_msrs) { - int i; - for (i = 0; i < kvm_feature_msrs->nmsrs; i++) - if (kvm_feature_msrs->indices[i] == MSR_IA32_ARCH_CAPABILITIES) { - kvm_msr_entry_add(cpu, MSR_IA32_ARCH_CAPABILITIES, - env->features[FEAT_ARCH_CAPABILITIES]); - break; - } + if (has_msr_arch_capabs) { + kvm_msr_entry_add(cpu, MSR_IA32_ARCH_CAPABILITIES, + env->features[FEAT_ARCH_CAPABILITIES]); } /* From 30a759b61a9247378a9cb84fbe4e437ae66e0461 Mon Sep 17 00:00:00 2001 From: Roman Kagan Date: Mon, 26 Nov 2018 15:28:44 +0000 Subject: [PATCH 2/2] hw/hyperv: fix NULL dereference with pure-kvm SynIC MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When started in compat configuration of SynIC, e.g. qemu-system-x86_64 -machine pc-i440fx-2.10,accel=kvm \ -cpu host,-vmx,hv-relaxed,hv_spinlocks=0x1fff,hv-vpindex,hv-synic or explicitly qemu-system-x86_64 -enable-kvm -cpu host,hv-synic,x-hv-synic-kvm-only=on QEMU crashes in hyperv_synic_reset() trying to access the non-present qobject for SynIC. Add the missing check for NULL. Reported-by: Vitaly Kuznetsov Reported-by: Igor Mammedov Fixes: 9b4cf107b09d18ac30f46fd1c4de8585ccba030c Fixes: 4a93722f9c279184e95b1e1ad775c01deec05065 Signed-off-by: Roman Kagan Message-Id: <20181126152836.25379-1-rkagan@virtuozzo.com> Reviewed-by: Philippe Mathieu-Daudé Tested-by: Philippe Mathieu-Daudé Signed-off-by: Eduardo Habkost --- hw/hyperv/hyperv.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/hw/hyperv/hyperv.c b/hw/hyperv/hyperv.c index a28e7249d8..8758635227 100644 --- a/hw/hyperv/hyperv.c +++ b/hw/hyperv/hyperv.c @@ -136,7 +136,11 @@ void hyperv_synic_add(CPUState *cs) void hyperv_synic_reset(CPUState *cs) { - device_reset(DEVICE(get_synic(cs))); + SynICState *synic = get_synic(cs); + + if (synic) { + device_reset(DEVICE(synic)); + } } static const TypeInfo synic_type_info = {