diff options
| author | Sean Christopherson <seanjc@google.com> | 2022-02-25 21:22:45 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-03-01 16:58:25 +0300 |
| commit | 527d5cd7eece9f9f5e9c5b6692cd6814a46df6fe (patch) | |
| tree | b61e88761f379f2842fed1fd46a83538c05b7381 /arch/x86/kvm/x86.c | |
| parent | 2f6f66ccd21e854cd3743bc8def68f8b4e7d91fc (diff) | |
| download | linux-527d5cd7eece9f9f5e9c5b6692cd6814a46df6fe.tar.xz | |
KVM: x86/mmu: Zap only obsolete roots if a root shadow page is zapped
Zap only obsolete roots when responding to zapping a single root shadow
page. Because KVM keeps root_count elevated when stuffing a previous
root into its PGD cache, shadowing a 64-bit guest means that zapping any
root causes all vCPUs to reload all roots, even if their current root is
not affected by the zap.
For many kernels, zapping a single root is a frequent operation, e.g. in
Linux it happens whenever an mm is dropped, e.g. process exits, etc...
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Message-Id: <20220225182248.3812651-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/x86.c')
| -rw-r--r-- | arch/x86/kvm/x86.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 18977693517a..cf17af4d6904 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9866,8 +9866,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) goto out; } } - if (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu)) - kvm_mmu_unload(vcpu); + if (kvm_check_request(KVM_REQ_MMU_FREE_OBSOLETE_ROOTS, vcpu)) + kvm_mmu_free_obsolete_roots(vcpu); if (kvm_check_request(KVM_REQ_MIGRATE_TIMER, vcpu)) __kvm_migrate_timers(vcpu); if (kvm_check_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu)) |