From 53692908b0f594285aba18ab848318262332ed25 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 18 Apr 2018 10:39:04 +0100 Subject: KVM: arm/arm64: vgic: Fix source vcpu issues for GICv2 SGI Now that we make sure we don't inject multiple instances of the same GICv2 SGI at the same time, we've made another bug more obvious: If we exit with an active SGI, we completely lose track of which vcpu it came from. On the next entry, we restore it with 0 as a source, and if that wasn't the right one, too bad. While this doesn't seem to trouble GIC-400, the architectural model gets offended and doesn't deactivate the interrupt on EOI. Another connected issue is that we will happilly make pending an interrupt from another vcpu, overriding the above zero with something that is just as inconsistent. Don't do that. The final issue is that we signal a maintenance interrupt when no pending interrupts are present in the LR. Assuming we've fixed the two issues above, we end-up in a situation where we keep exiting as soon as we've reached the active state, and not be able to inject the following pending. The fix comes in 3 parts: - GICv2 SGIs have their source vcpu saved if they are active on exit, and restored on entry - Multi-SGIs cannot go via the Pending+Active state, as this would corrupt the source field - Multi-SGIs are converted to using MI on EOI instead of NPIE Fixes: 16ca6a607d84bef0 ("KVM: arm/arm64: vgic: Don't populate multiple LRs with the same vintid") Reported-by: Mark Rutland Tested-by: Mark Rutland Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- include/kvm/arm_vgic.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 24f03941ada8..e7efe12a81bd 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -131,6 +131,7 @@ struct vgic_irq { u32 mpidr; /* GICv3 target VCPU */ }; u8 source; /* GICv2 SGIs only */ + u8 active_source; /* GICv2 SGIs only */ u8 priority; enum vgic_irq_config config; /* Level or edge */ -- cgit v1.2.3