Message ID | 69b79ab2-0acc-5980-9a79-8c477aa33868@suse.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | x86/HVM: don't mark external IRQs as pending when vLAPIC is disabled | expand |
On 21/11/2022 12:13, Jan Beulich wrote: > In software-disabled state an LAPIC does not accept any interrupt > requests and hence no IRR bit would newly become set while in this > state. As a result it is also wrong for us to mark IO-APIC or MSI > originating vectors as having a pending request when the vLAPIC is in > this state. Such interrupts are simply lost. > > Introduce (IO-APIC) or re-use (MSI) a local variable to help > readability. > > Fixes: 4fe21ad3712e ("This patch add virtual IOAPIC support for VMX guest") > Fixes: 85715f4bc7c9 ("MSI 5/6: add MSI support to passthrough HVM domain") > Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
--- a/xen/arch/x86/hvm/vioapic.c +++ b/xen/arch/x86/hvm/vioapic.c @@ -460,9 +460,14 @@ static void vioapic_deliver(struct hvm_v case dest_Fixed: for_each_vcpu ( d, v ) - if ( vlapic_match_dest(vcpu_vlapic(v), NULL, 0, dest, dest_mode) ) - ioapic_inj_irq(vioapic, vcpu_vlapic(v), vector, trig_mode, + { + struct vlapic *vlapic = vcpu_vlapic(v); + + if ( vlapic_enabled(vlapic) && + vlapic_match_dest(vlapic, NULL, 0, dest, dest_mode) ) + ioapic_inj_irq(vioapic, vlapic, vector, trig_mode, delivery_mode); + } break; case dest_NMI: --- a/xen/arch/x86/hvm/vmsi.c +++ b/xen/arch/x86/hvm/vmsi.c @@ -87,10 +87,12 @@ int vmsi_deliver( case dest_Fixed: for_each_vcpu ( d, v ) - if ( vlapic_match_dest(vcpu_vlapic(v), NULL, - 0, dest, dest_mode) ) - vmsi_inj_irq(vcpu_vlapic(v), vector, - trig_mode, delivery_mode); + { + target = vcpu_vlapic(v); + if ( vlapic_enabled(target) && + vlapic_match_dest(target, NULL, 0, dest, dest_mode) ) + vmsi_inj_irq(target, vector, trig_mode, delivery_mode); + } break; default:
In software-disabled state an LAPIC does not accept any interrupt requests and hence no IRR bit would newly become set while in this state. As a result it is also wrong for us to mark IO-APIC or MSI originating vectors as having a pending request when the vLAPIC is in this state. Such interrupts are simply lost. Introduce (IO-APIC) or re-use (MSI) a local variable to help readability. Fixes: 4fe21ad3712e ("This patch add virtual IOAPIC support for VMX guest") Fixes: 85715f4bc7c9 ("MSI 5/6: add MSI support to passthrough HVM domain") Signed-off-by: Jan Beulich <jbeulich@suse.com>