If multiple VMRUN instructions fail, resulting in calls to dump_vmcb(), the output can become interleaved and it is impossible to identify which line of output belongs to which VMCB. Add a mutex to dump_vmcb() so that the output is serialized. Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx> --- arch/x86/kvm/svm/svm.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 99f2d9de6ce2..5b62ac06a19e 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -29,6 +29,7 @@ #include <linux/cc_platform.h> #include <linux/smp.h> #include <linux/string_choices.h> +#include <linux/mutex.h> #include <asm/apic.h> #include <asm/perf_event.h> @@ -249,6 +250,8 @@ static unsigned long iopm_base; DEFINE_PER_CPU(struct svm_cpu_data, svm_data); +static DEFINE_MUTEX(vmcb_dump_mutex); + /* * Only MSR_TSC_AUX is switched via the user return hook. EFER is switched via * the VMCB, and the SYSCALL/SYSENTER MSRs are handled by VMLOAD/VMSAVE. @@ -3385,6 +3388,8 @@ static void dump_vmcb(struct kvm_vcpu *vcpu) return; } + guard(mutex)(&vmcb_dump_mutex); + vm_type = sev_snp_guest(vcpu->kvm) ? "SEV-SNP" : sev_es_guest(vcpu->kvm) ? "SEV-ES" : sev_guest(vcpu->kvm) ? "SEV" : "SVM"; -- 2.46.2
