From 1f7e378d1235a3cb5c9cdd8c62fe13cb6c3cf157 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 6 Sep 2016 14:02:08 +0100 Subject: arm: KVM: Preserve pending Virtual Abort in world switch The HCR.VA bit is used to signal an Abort to a guest, and has the peculiar feature of getting cleared when the guest has taken the abort (this is the only bit that behaves as such in this register). This means that if we signal such an abort, we must leave it in the guest context until it disappears from HCR, and at which point it must be cleared from the context. Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/hyp/switch.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/arm') diff --git a/arch/arm/kvm/hyp/switch.c b/arch/arm/kvm/hyp/switch.c index 37b336549700..9da16fd1005f 100644 --- a/arch/arm/kvm/hyp/switch.c +++ b/arch/arm/kvm/hyp/switch.c @@ -54,6 +54,15 @@ static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu) { u32 val; + /* + * If we pended a virtual abort, preserve it until it gets + * cleared. See B1.9.9 (Virtual Abort exception) for details, + * but the crucial bit is the zeroing of HCR.VA in the + * pseudocode. + */ + if (vcpu->arch.hcr & HCR_VA) + vcpu->arch.hcr = read_sysreg(HCR); + write_sysreg(0, HCR); write_sysreg(0, HSTR); val = read_sysreg(HDCR); -- cgit