From af723545ed34851ad500b4e92395dc7b2c58b8fd Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Tue, 16 Aug 2022 19:25:54 +0000 Subject: [PATCH] UPSTREAM: KVM: arm64: Reject 32bit user PSTATE on asymmetric systems 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. Bug: 254441685 Fixes: 2122a833316f ("arm64: Allow mismatched 32-bit EL0 support") Signed-off-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220816192554.1455559-3-oliver.upton@linux.dev (cherry picked from commit b10d86fb8e46cc812171728bcd326df2f34e9ed5) Signed-off-by: Lee Jones Change-Id: I73b63bf79bfbade51dc417fe2c76fd0057eb21b8 --- 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 c763808cacdf..27b783a711bb 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -225,7 +225,7 @@ 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: