From: Roger Pau Monne Date: Mon, 27 Jul 2020 17:05:36 +0000 (+0200) Subject: x86/hvm: don't force vCPU 0 for IRQ 0 when using fixed destination mode X-Git-Tag: 4.15.0-rc1~963 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=ab5bfc049e8e04bca66d591ab439d2341623f83c;p=people%2Fjgross%2Fxen.git x86/hvm: don't force vCPU 0 for IRQ 0 when using fixed destination mode When the IO APIC pin mapped to the ISA IRQ 0 has been configured to use fixed delivery mode, do not forcefully route interrupts to vCPU 0, as the OS might have setup those interrupts to be injected to a different vCPU, and injecting to vCPU 0 can cause the OS to miss such interrupts or errors to happen due to unexpected vectors being injected on vCPU 0. In order to fix remove such handling altogether for fixed destination mode pins and just inject them according to the data setup in the IO-APIC entry. Signed-off-by: Roger Pau Monné Reviewed-by: Jan Beulich --- diff --git a/xen/arch/x86/hvm/vioapic.c b/xen/arch/x86/hvm/vioapic.c index b00037ea87..123191db75 100644 --- a/xen/arch/x86/hvm/vioapic.c +++ b/xen/arch/x86/hvm/vioapic.c @@ -438,26 +438,11 @@ static void vioapic_deliver(struct hvm_vioapic *vioapic, unsigned int pin) } case dest_Fixed: - { -#ifdef IRQ0_SPECIAL_ROUTING - /* Do not deliver timer interrupts to VCPU != 0 */ - if ( (irq == hvm_isa_irq_to_gsi(0)) && pt_active(&d->arch.vpit.pt0) ) - { - if ( (v = d->vcpu ? d->vcpu[0] : NULL) != NULL ) - ioapic_inj_irq(vioapic, vcpu_vlapic(v), vector, - trig_mode, delivery_mode); - } - else -#endif - { - 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, delivery_mode); - } + 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, + delivery_mode); break; - } case dest_NMI: {