From c0fe7b099931c6c05c98a05c277185ee25254f35 Mon Sep 17 00:00:00 2001 From: Bharat Bhushan Date: Mon, 5 Mar 2012 01:34:08 +0000 Subject: Restore guest CR after exit timing calculation No instruction which can change Condition Register (CR) should be executed after Guest CR is loaded. So the guest CR is restored after the Exit Timing in lightweight_exit executes cmpw, which can clobber CR. Signed-off-by: Bharat Bhushan Signed-off-by: Alexander Graf Signed-off-by: Avi Kivity diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S index 57e2fa4..909e96e 100644 --- a/arch/powerpc/kvm/bookehv_interrupts.S +++ b/arch/powerpc/kvm/bookehv_interrupts.S @@ -580,7 +580,6 @@ lightweight_exit: mtlr r3 mtxer r5 mtctr r6 - mtcr r7 mtsrr0 r8 mtsrr1 r9 @@ -588,14 +587,20 @@ lightweight_exit: /* save enter time */ 1: mfspr r6, SPRN_TBRU - mfspr r7, SPRN_TBRL + mfspr r9, SPRN_TBRL mfspr r8, SPRN_TBRU cmpw r8, r6 - PPC_STL r7, VCPU_TIMING_LAST_ENTER_TBL(r4) + PPC_STL r9, VCPU_TIMING_LAST_ENTER_TBL(r4) bne 1b PPC_STL r8, VCPU_TIMING_LAST_ENTER_TBU(r4) #endif + /* + * Don't execute any instruction which can change CR after + * below instruction. + */ + mtcr r7 + /* Finish loading guest volatiles and jump to guest. */ PPC_LL r5, VCPU_GPR(r5)(r4) PPC_LL r6, VCPU_GPR(r6)(r4) -- cgit v0.10.2