From: Marc Zyngier <marc.zyngier@xxxxxxx>
This patch has been added to the 4.1 stable tree. If you have any
objections, please let us know.
===============
[ Upstream commit acfb3b883f6d6a4b5d27ad7fdded11f6a09ae6dd ]
KVM doesn't follow the SMCCC when it comes to unimplemented calls,
and inject an UNDEF instead of returning an error. Since firmware
calls are now used for security mitigation, they are becoming more
common, and the undef is counter productive.
Instead, let's follow the SMCCC which states that -1 must be returned
to the caller when getting an unknown function number.
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
arch/arm64/kvm/handle_exit.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 524fa25671fc..2d357aed5e66 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -42,7 +42,7 @@ static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run)
ret = kvm_psci_call(vcpu);
if (ret < 0) {
- kvm_inject_undefined(vcpu);
+ vcpu_set_reg(vcpu, 0, ~0UL);
return 1;
}
@@ -51,7 +51,7 @@ static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run)
static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
- kvm_inject_undefined(vcpu);
+ vcpu_set_reg(vcpu, 0, ~0UL);
return 1;
}
--
2.14.1