If we hit any exception whatsoever in the restore path and r1/r2 aren't the host registers, we don't get a working oops. So it's always a good idea to restore them as early as possible. This time, it actually has practical reasons to do so too, since we need to have the host page fault handler fix up our guest instruction read code. And for that to work we need r1/r2 restored. Signed-off-by: Alexander Graf <agraf@xxxxxxx> --- arch/powerpc/kvm/bookehv_interrupts.S | 12 ++++++------ 1 files changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S index 9eaeebd..63023ae 100644 --- a/arch/powerpc/kvm/bookehv_interrupts.S +++ b/arch/powerpc/kvm/bookehv_interrupts.S @@ -67,6 +67,12 @@ * saved in vcpu: cr, ctr, r3-r13 */ .macro kvm_handler_common intno, srr0, flags + /* Restore host stack pointer */ + PPC_STL r1, VCPU_GPR(r1)(r4) + PPC_STL r2, VCPU_GPR(r2)(r4) + PPC_LL r1, VCPU_HOST_STACK(r4) + PPC_LL r2, HOST_R2(r1) + mfspr r10, SPRN_PID lwz r8, VCPU_HOST_PID(r4) PPC_LL r11, VCPU_SHARED(r4) @@ -290,10 +296,8 @@ _GLOBAL(kvmppc_resume_host) /* Save remaining volatile guest register state to vcpu. */ mfspr r3, SPRN_VRSAVE PPC_STL r0, VCPU_GPR(r0)(r4) - PPC_STL r1, VCPU_GPR(r1)(r4) mflr r5 mfspr r6, SPRN_SPRG4 - PPC_STL r2, VCPU_GPR(r2)(r4) PPC_STL r5, VCPU_LR(r4) mfspr r7, SPRN_SPRG5 PPC_STL r3, VCPU_VRSAVE(r4) @@ -334,10 +338,6 @@ _GLOBAL(kvmppc_resume_host) mtspr SPRN_EPCR, r3 isync - /* Restore host stack pointer */ - PPC_LL r1, VCPU_HOST_STACK(r4) - PPC_LL r2, HOST_R2(r1) - /* Switch to kernel stack and jump to handler. */ PPC_LL r3, HOST_RUN(r1) mr r5, r14 /* intno */ -- 1.6.0.2 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
