@@ -7081,8 +7081,10 @@ static void kvm_init_msr_list(void)
for (i = 0; i < ARRAY_SIZE(msrs_to_save_base); i++)
kvm_probe_msr_to_save(msrs_to_save_base[i]);
- for (i = 0; i < ARRAY_SIZE(msrs_to_save_pmu); i++)
- kvm_probe_msr_to_save(msrs_to_save_pmu[i]);
+ if (enable_pmu) {
+ for (i = 0; i < ARRAY_SIZE(msrs_to_save_pmu); i++)
+ kvm_probe_msr_to_save(msrs_to_save_pmu[i]);
+ }
for (i = 0; i < ARRAY_SIZE(emulated_msrs_all); i++) {
if (!static_call(kvm_x86_has_emulated_msr)(NULL, emulated_msrs_all[i]))
Omit all PMU MSRs from the "MSRs to save" list if the PMU is disabled so that userspace doesn't waste time saving and restoring dummy values. KVM provides "error" semantics (read zeros, drop writes) for such known-but- unsupported MSRs, i.e. has fudged around this issue for quite some time. Keep the "error" semantics as-is for now, the logic will be cleaned up in a separate patch. Cc: Aaron Lewis <aaronlewis@google.com> Cc: Weijiang Yang <weijiang.yang@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/kvm/x86.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)