[PATCH v1 2/2] KVM: arm64: nv: update CPU register PAR_EL1 after 'at s*'

[Volodymyr Babchuk]

Previously this code update only vCPU's in-memory value, which is good,
but not enough, as there will be no context switch after exiting
exception handler, so in-memory value will not get into actual
register.

It worked good enough for VHE guests because KVM code tried fast path,
which of course updated real PAR_EL1.

Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk at epam.com>
---
 arch/arm64/kvm/sys_regs.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 7b8a0a6f26468..ab2b5e261d312 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -3463,6 +3463,9 @@ static bool handle_at_s1e2(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 
 	__kvm_at_s1e2(vcpu, op, p->regval);
 
+	/* No context switch happened, so we need to update PAR_EL1 manually */
+	write_sysreg(vcpu_read_sys_reg(vcpu, PAR_EL1), par_el1);
+
 	return true;
 }
 
@@ -3473,6 +3476,9 @@ static bool handle_at_s12(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 
 	__kvm_at_s12(vcpu, op, p->regval);
 
+	/* No context switch happened, so we need to update PAR_EL1 manually */
+	write_sysreg(vcpu_read_sys_reg(vcpu, PAR_EL1), par_el1);
+
 	return true;
 }
 
-- 
2.50.1