[PULL 26/50] arm: KVM: Preserve pending Virtual Abort in world switch

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Marc Zyngier <marc.zyngier@xxxxxxx>

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@xxxxxxx>
Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
---
 arch/arm/kvm/hyp/switch.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/arm/kvm/hyp/switch.c b/arch/arm/kvm/hyp/switch.c
index 37b3365..9da16fd 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);
-- 
2.9.0

--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux