[PATCH v6 04/64] KVM: arm64: nv: Allow userspace to set PSR_MODE_EL2x

Marc Zyngier
2022-01-28T12:19:35Z

From: Christoffer Dall <christoffer.dall@linaro.org>

We were not allowing userspace to set a more privileged mode for the VCPU
than EL1, but we should allow this when nested virtualization is enabled
for the VCPU.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/guest.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index e116c7767730..db6209622be9 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -24,6 +24,7 @@
#include <asm/fpsimd.h>
#include <asm/kvm.h>
#include <asm/kvm_emulate.h>
+#include <asm/kvm_nested.h>
#include <asm/sigcontext.h>

#include "trace.h"
@@ -259,6 +260,11 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
if (vcpu_el1_is_32bit(vcpu))
return -EINVAL;
break;
+ case PSR_MODE_EL2h:
+ case PSR_MODE_EL2t:
+ if (vcpu_el1_is_32bit(vcpu) || !vcpu_has_nv(vcpu))
+ return -EINVAL;
+ break;
default:
err = -EINVAL;
goto out;