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[10/19] arm: KVM: Preserve pending Virtual Abort in world switch

Message ID 1473166937-15271-11-git-send-email-marc.zyngier@arm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Marc Zyngier Sept. 6, 2016, 1:02 p.m. UTC
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 <marc.zyngier@arm.com>
---
 arch/arm/kvm/hyp/switch.c | 9 +++++++++
 1 file changed, 9 insertions(+)
diff mbox

Patch

diff --git a/arch/arm/kvm/hyp/switch.c b/arch/arm/kvm/hyp/switch.c
index b13caa9..8cda887 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);