| Message ID | 20201109213023.15092-4-will@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | An alternative series for asymmetric AArch32 systems | expand |
On 2020-11-09 21:30, Will Deacon wrote: > If a vCPU tries to run 32-bit code on a system with mismatched support nit: s/tries to run/is caught running/ > at EL0, then we should kill it. > > Signed-off-by: Will Deacon <will@kernel.org> > --- > arch/arm64/kvm/arm.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index 5750ec34960e..d322ac0f4a8e 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -633,6 +633,15 @@ 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 > @@ -816,7 +825,7 @@ 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 Acked-by: Marc Zyngier <maz@kernel.org> M.
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 5750ec34960e..d322ac0f4a8e 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -633,6 +633,15 @@ 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 @@ -816,7 +825,7 @@ 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
If a vCPU tries to run 32-bit code on a system with mismatched support at EL0, then we should kill it. Signed-off-by: Will Deacon <will@kernel.org> --- arch/arm64/kvm/arm.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)