| Message ID | 20211220094950.288692-1-pbonzini@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [for-stable] KVM: VMX: clear vmx_x86_ops.sync_pir_to_irr if APICv is disabled | expand |
On Mon, Dec 20, 2021 at 10:49:50AM +0100, Paolo Bonzini wrote: > commit e90e51d5f01d2baae5dcce280866bbb96816e978 upstream. > > There is nothing to synchronize if APICv is disabled, since neither > other vCPUs nor assigned devices can set PIR.ON. > > After the patch was committed to Linus's tree, it was observed that > this fixes an issue with commit 7e1901f6c86c ("KVM: VMX: prepare > sync_pir_to_irr for running with APICv disabled", backported to stable > as e.g. commit 70a37e04c08a for the 5.15 tree). Without this patch, > vmx_sync_pir_to_irr can be reached with enable_apicv == false, triggering > > if (KVM_BUG_ON(!enable_apicv, vcpu->kvm)) > > Fixes: 7e1901f6c86c ("KVM: VMX: prepare sync_pir_to_irr for running with APICv disabled") > Cc: stable@vger.kernel.org > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > --- > arch/x86/kvm/vmx/vmx.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) Looks like it is already queued up, thanks. greg k-h
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index dacdf2395f01..4e212f04268b 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7776,10 +7776,10 @@ static __init int hardware_setup(void) ple_window_shrink = 0; } - if (!cpu_has_vmx_apicv()) { + if (!cpu_has_vmx_apicv()) enable_apicv = 0; + if (!enable_apicv) vmx_x86_ops.sync_pir_to_irr = NULL; - } if (cpu_has_vmx_tsc_scaling()) { kvm_has_tsc_control = true;
commit e90e51d5f01d2baae5dcce280866bbb96816e978 upstream. There is nothing to synchronize if APICv is disabled, since neither other vCPUs nor assigned devices can set PIR.ON. After the patch was committed to Linus's tree, it was observed that this fixes an issue with commit 7e1901f6c86c ("KVM: VMX: prepare sync_pir_to_irr for running with APICv disabled", backported to stable as e.g. commit 70a37e04c08a for the 5.15 tree). Without this patch, vmx_sync_pir_to_irr can be reached with enable_apicv == false, triggering if (KVM_BUG_ON(!enable_apicv, vcpu->kvm)) Fixes: 7e1901f6c86c ("KVM: VMX: prepare sync_pir_to_irr for running with APICv disabled") Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- arch/x86/kvm/vmx/vmx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)