| Message ID | 1544623390-18710-5-git-send-email-diana.craciun@nxp.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 98518c4d8728656db349f875fcbbc7c126d4c973 |
| Headers | show |
| Series | powerpc/fsl: NXP PowerPC Spectre variant 2 workarounds | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | next/apply_patch Successfully applied |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 11 lines checked |
diff --git a/arch/powerpc/kvm/e500_emulate.c b/arch/powerpc/kvm/e500_emulate.c index 3f8189e..d0eb670 100644 --- a/arch/powerpc/kvm/e500_emulate.c +++ b/arch/powerpc/kvm/e500_emulate.c @@ -276,6 +276,11 @@ int kvmppc_core_emulate_mtspr_e500(struct kvm_vcpu *vcpu, int sprn, ulong spr_va */ vcpu->arch.pwrmgtcr0 = spr_val; break; + /* if we are here, it means that we have already flushed the + * branch predictor, so just return to guest + */ + case SPRN_BUCSR: + break; /* extra exceptions */ #ifdef CONFIG_SPE_POSSIBLE
In order to flush the branch predictor the guest kernel performs writes to the BUCSR register which is hypervisor privilleged. However, the branch predictor is flushed at each KVM entry, so the branch predictor has been already flushed, so just return as soon as possible to guest. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> --- arch/powerpc/kvm/e500_emulate.c | 5 +++++ 1 file changed, 5 insertions(+)