Commit 2f6a49bb authored by Will Deacon's avatar Will Deacon
Browse files

KVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support 



If a vCPU is caught running 32-bit code on a system with mismatched
support at EL0, then we should kill it.

Acked-by: default avatarMarc Zyngier <maz@kernel.org>
Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210608180313.11502-4-will@kernel.org


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 2122a833

arch/arm64/kvm/arm.c

+10 −1
Original line number Diff line number Diff line
@@ -692,6 +692,15 @@ static void check_vcpu_requests(struct kvm_vcpu *vcpu) 
	}

}



static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)

{

	if (likely(!vcpu_mode_is_32bit(vcpu)))

		return false;



	return !system_supports_32bit_el0() ||

		static_branch_unlikely(&arm64_mismatched_32bit_el0);

}



/**

 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code

 * @vcpu:	The VCPU pointer
@@ -875,7 +884,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 
		 * with the asymmetric AArch32 case), return to userspace with

		 * a fatal error.

		 */

		if (!system_supports_32bit_el0() && vcpu_mode_is_32bit(vcpu)) {

		if (vcpu_mode_is_bad_32bit(vcpu)) {

			/*

			 * As we have caught the guest red-handed, decide that

			 * it isn't fit for purpose anymore by making the vcpu