On Fri, Feb 09, 2018 at 06:50:14PM +0000, Julien Grall wrote:

Hi Christoffer,

On 01/12/2018 12:07 PM, Christoffer Dall wrote:

quoted

There's a semantic difference between the EL1 registers that control
operation of a kernel running in EL1 and EL1 registers that only control
userspace execution in EL0.  Since we can defer saving/restoring the
latter, move them into their own function.

We also take this chance to rename the function saving/restoring the
remaining system register to make it clear this function deals with
the EL1 system registers.

No functional change.

Reviewed-by: Andrew Jones <redacted>
Signed-off-by: Christoffer Dall <redacted>
---
 arch/arm64/kvm/hyp/sysreg-sr.c | 46 +++++++++++++++++++++++++++++++-----------
 1 file changed, 34 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c
index 848a46eb33bf..99dd50ce483b 100644
--- a/arch/arm64/kvm/hyp/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/sysreg-sr.c

@@ -34,18 +34,27 @@ static void __hyp_text __sysreg_do_nothing(struct kvm_cpu_context *ctxt) { }
 static void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt)
 {
-	ctxt->sys_regs[ACTLR_EL1]	= read_sysreg(actlr_el1);

I am a bit confused, the comment on top of the function says the host must
save ACTLR_EL1 in the VHE case. But AFAICT, after this patch the register
will not get saved in the host context. Did I miss anything?

You're right, there is indeed a functional change here, introduced in
v2.

I have adjusted the commentary and the patch description.

Thanks,
-Christoffer