From: Oliver Upton oliver.upton@linux.dev
[ Upstream commit b10d86fb8e46cc812171728bcd326df2f34e9ed5 ]
KVM does not support AArch32 EL0 on asymmetric systems. To that end, prevent userspace from configuring a vCPU in such a state through setting PSTATE.
It is already ABI that KVM rejects such a write on a system where AArch32 EL0 is unsupported. Though the kernel's definition of a 32bit system changed in commit 2122a833316f ("arm64: Allow mismatched 32-bit EL0 support"), KVM's did not.
Fixes: 2122a833316f ("arm64: Allow mismatched 32-bit EL0 support") Signed-off-by: Oliver Upton oliver.upton@linux.dev Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20220816192554.1455559-3-oliver.upton@linux.dev Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm64/kvm/guest.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 8c607199cad1..f802a3b3f8db 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -242,7 +242,7 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) u64 mode = (*(u64 *)valp) & PSR_AA32_MODE_MASK; switch (mode) { case PSR_AA32_MODE_USR: - if (!system_supports_32bit_el0()) + if (!kvm_supports_32bit_el0()) return -EINVAL; break; case PSR_AA32_MODE_FIQ: