From: Bharat Bhushan <r65777@xxxxxxxxxxxxx> 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 <bharat.bhushan@xxxxxxxxxxxxx> Signed-off-by: Alexander Graf <agraf@xxxxxxx> --- arch/powerpc/kvm/bookehv_interrupts.S | 11 ++++++++--- 1 files changed, 8 insertions(+), 3 deletions(-) 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) -- 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
