KVM: arm64: nv: Allow userspace to set PSR_MODE_EL2x

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>
Link: https://lore.kernel.org/r/20230209175820.1939006-6-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 5626ddb..63643c9 100644 (file)
--- 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"
@@ -253,6 +254,11 @@ 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_has_nv(vcpu))
+                               return -EINVAL;
+                       fallthrough;
                case PSR_MODE_EL0t:
                case PSR_MODE_EL1t:
                case PSR_MODE_EL1h: