On Wed, Mar 14, 2018 at 04:50:42PM +0000, Marc Zyngier wrote: > All our useful entry points into the hypervisor are starting by > saving x0 and x1 on the stack. Let's move those into the vectors > by introducing macros that annotate whether a vector is valid or > not, thus indicating whether we want to stash registers or not. > > The only drawback is that we now also stash registers for el2_error, > but this should never happen, and we pop them back right at the > start of the handling sequence. > > Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> > --- > arch/arm64/kvm/hyp/hyp-entry.S | 56 ++++++++++++++++++++++++------------------ > 1 file changed, 32 insertions(+), 24 deletions(-) > > diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S > index f36464bd57c5..0f62b5f76aa5 100644 > --- a/arch/arm64/kvm/hyp/hyp-entry.S > +++ b/arch/arm64/kvm/hyp/hyp-entry.S > @@ -55,7 +55,6 @@ ENTRY(__vhe_hyp_call) > ENDPROC(__vhe_hyp_call) > > el1_sync: // Guest trapped into EL2 > - stp x0, x1, [sp, #-16]! > > alternative_if_not ARM64_HAS_VIRT_HOST_EXTN > mrs x1, esr_el2 > @@ -137,18 +136,18 @@ alternative_else_nop_endif > b __guest_exit > > el1_irq: > - stp x0, x1, [sp, #-16]! > ldr x1, [sp, #16 + 8] > mov x0, #ARM_EXCEPTION_IRQ > b __guest_exit > > el1_error: > - stp x0, x1, [sp, #-16]! > ldr x1, [sp, #16 + 8] > mov x0, #ARM_EXCEPTION_EL1_SERROR > b __guest_exit > > el2_error: > + ldp x0, x1, [sp], #16 > + Nitpick: you don't need a memory access here, just: add sp, sp, #16 (unless el2_error has changed somewhere before this patch) -- Catalin _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
