| Message ID | 20230408160427.10672-6-maz@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: Synchronise speculative page table walks on translation regime change | expand |
On Sat, Apr 08, 2023 at 05:04:27PM +0100, Marc Zyngier wrote: > __kvm_vcpu_run_vhe() end on VHE with an isb(). However, this > function is only reachable via kvm_call_hyp_ret(), which already > contains an isb() in order to mimick the behaviour of nVHE and > provide a context synchronisation event. > > We thus have two isb()s back to back, which is one too many. > Drop the first one and solely rely on the one in the helper. > > Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index cd3f3117bf16..3d868e84c7a0 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -227,11 +227,10 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu) /* * When we exit from the guest we change a number of CPU configuration - * parameters, such as traps. Make sure these changes take effect - * before running the host or additional guests. + * parameters, such as traps. We rely on the isb() in kvm_call_hyp*() + * to make sure these changes take effect before running the host or + * additional guests. */ - isb(); - return ret; }
__kvm_vcpu_run_vhe() end on VHE with an isb(). However, this function is only reachable via kvm_call_hyp_ret(), which already contains an isb() in order to mimick the behaviour of nVHE and provide a context synchronisation event. We thus have two isb()s back to back, which is one too many. Drop the first one and solely rely on the one in the helper. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/kvm/hyp/vhe/switch.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)