Commit 21aecdbd authored Jan 21, 2020 by James Morse Committed by Marc Zyngier Jan 23, 2020

KVM: arm: Make inject_abt32() inject an external abort instead



KVM's inject_abt64() injects an external-abort into an aarch64 guest.
The KVM_CAP_ARM_INJECT_EXT_DABT is intended to do exactly this, but
for an aarch32 guest inject_abt32() injects an implementation-defined
exception, 'Lockdown fault'.

Change this to external abort. For non-LPAE we now get the documented:
| Unhandled fault: external abort on non-linefetch (0x008) at 0x9c800f00
and for LPAE:
| Unhandled fault: synchronous external abort (0x210) at 0x9c800f00

Fixes: 74a64a98 ("KVM: arm/arm64: Unify 32bit fault injection")
Reported-by: Beata Michalska <beata.michalska@linaro.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200121123356.203000-3-james.morse@arm.com

parent 018f22f9

virt/kvm/arm/aarch32.c

+7 −3

Original line number	Diff line number	Diff line
		@@ -15,6 +15,10 @@
		#include <asm/kvm_emulate.h>
		#include <asm/kvm_hyp.h>

		#define DFSR_FSC_EXTABT_LPAE 0x10
		#define DFSR_FSC_EXTABT_nLPAE 0x08
		#define DFSR_LPAE BIT(9)

		/*
		* Table taken from ARMv8 ARM DDI0487B-B, table G1-10.
		*/
		@@ -182,10 +186,10 @@ static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt,
		/* Give the guest an IMPLEMENTATION DEFINED exception */
		is_lpae = (vcpu_cp15(vcpu, c2_TTBCR) >> 31);
		if (is_lpae) {
		*fsr = 1 << 9 \| 0x34;
		*fsr = DFSR_LPAE \| DFSR_FSC_EXTABT_LPAE;
		} else {
		/* Surprise! DFSR's FS[4] lives in bit 10 */
		fsr = BIT(10) \| 0x4; / 0x14 */
		/* no need to shuffle FS[4] into DFSR[10] as its 0 */
		*fsr = DFSR_FSC_EXTABT_nLPAE;
		}
		}

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