If calling into the AT code from guest EL1, there is no need
to consider any context switch, as we are guaranteed to be
in the correct context.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/kvm/at.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c
index 76745e81bd9c8..6e767ae3c495a 100644
--- a/arch/arm64/kvm/at.c
+++ b/arch/arm64/kvm/at.c
@@ -1294,7 +1294,7 @@ static u64 __kvm_at_s1e01_fast(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
{
struct mmu_config config;
struct kvm_s2_mmu *mmu;
- bool fail;
+ bool fail, mmu_cs;
u64 par;
par = SYS_PAR_EL1_F;
@@ -1310,8 +1310,13 @@ static u64 __kvm_at_s1e01_fast(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
* If HCR_EL2.{E2H,TGE} == {1,1}, the MMU context is already
* the right one (as we trapped from vEL2). If not, save the
* full MMU context.
+ *
+ * We are also guaranteed to be in the correct context if
+ * we're not in a nested VM.
*/
- if (vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu))
+ mmu_cs = (vcpu_has_nv(vcpu) &&
+ !(vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)));
+ if (!mmu_cs)
goto skip_mmu_switch;
/*
@@ -1379,7 +1384,7 @@ static u64 __kvm_at_s1e01_fast(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
write_sysreg_hcr(HCR_HOST_VHE_FLAGS);
- if (!(vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)))
+ if (mmu_cs)
__mmu_config_restore(&config);
return par;
--
2.39.2
