On 21/03/17 19:20, Marc Zyngier wrote: > At the moment, we only save/restore lr if on VHE, as we rely only > the EL1 code to have preserved it in the non-VHE case. > > As we're about to get rid of the latter, let's move the save/restore > code to the do_el2_call macro, unifying both code paths. > > Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> > --- > arch/arm64/kvm/hyp/hyp-entry.S | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S > index 5e9052f087f2..d8ef788646c6 100644 > --- a/arch/arm64/kvm/hyp/hyp-entry.S > +++ b/arch/arm64/kvm/hyp/hyp-entry.S > @@ -32,17 +32,17 @@ > * Shuffle the parameters before calling the function > * pointed to in x0. Assumes parameters in x[1,2,3]. > */ > + str lr, [sp, #-16]! > mov lr, x0 > mov x0, x1 > mov x1, x2 > mov x2, x3 > blr lr > + ldr lr, [sp], #16 > .endm > > ENTRY(__vhe_hyp_call) > - str lr, [sp, #-16]! > do_el2_call > - ldr lr, [sp], #16 > /* > * We used to rely on having an exception return to get > * an implicit isb. In the E2H case, we don't have it anymore. > As a follow-up on this patch, here's a nit I missed where we were still saving lr in the EL2 entry code. Doesn't affect functionality, but might as well clean that one up (and kill an obscure comment): diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index 09391cf0c93c..952f6cb9cf72 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -38,13 +38,10 @@ * A function pointer with a value less than 0xfff has a special meaning, * and is used to implement hyp stubs in the same way as in * arch/arm64/kernel/hyp_stub.S. - * HVC behaves as a 'bl' call and will clobber lr. */ ENTRY(__kvm_call_hyp) alternative_if_not ARM64_HAS_VIRT_HOST_EXTN - str lr, [sp, #-16]! hvc #0 - ldr lr, [sp], #16 ret alternative_else_nop_endif b __vhe_hyp_call I'll squash it locally. Thanks, M. -- Jazz is not dead. It just smells funny...
