[PATCH] arm64: KVM: VHE: save and restore some PSTATE bits

when exit from guest, some host PSTATE bits may be lost, such as
PSTATE.PAN or PSTATE.UAO. It is because host and hypervisor all run
in the EL2, host PSTATE value cannot be saved and restored via
SPSR_EL2. So if guest has changed the PSTATE, host continues with
a wrong value guest has set.

Signed-off-by: Dongjiu Geng <redacted>
Signed-off-by: Haibin Zhang <redacted>
---
 arch/arm64/include/asm/kvm_host.h |  8 +++++++
 arch/arm64/include/asm/kvm_hyp.h  |  2 ++
 arch/arm64/include/asm/sysreg.h   | 23 +++++++++++++++++++
 arch/arm64/kvm/hyp/entry.S        |  2 --
 arch/arm64/kvm/hyp/switch.c       | 24 ++++++++++++++++++--
 arch/arm64/kvm/hyp/sysreg-sr.c    | 48 ++++++++++++++++++++++++++++++++++++---
 6 files changed, 100 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index e923b58..cba7d3e 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h

@@ -193,6 +193,12 @@ struct kvm_cpu_context {
 	};
 };
 
+struct kvm_cpu_host_pstate {
+	u64 daif;
+	u64 uao;
+	u64 pan;
+};