The machine_check_handle_early hypervisor guest test is skipped if !HVMODE or MSR[HV]=0, which is wrong for PR or nested hypervisors that could be running a guest in this state.
Test HSTATE_IN_GUEST up front and use that to branch out to the KVM handler, then MSR[PR] alone can test for this kernel's userspace. This matches all other interrupt handling. Signed-off-by: Nicholas Piggin <npig...@gmail.com> --- arch/powerpc/kernel/exceptions-64s.S | 33 +++++++++++----------------- 1 file changed, 13 insertions(+), 20 deletions(-) diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index e8734a1dfdb9..5789a00691f9 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -1108,11 +1108,8 @@ EXC_COMMON_BEGIN(machine_check_handle_early) bl machine_check_early std r3,RESULT(r1) /* Save result */ ld r12,_MSR(r1) -BEGIN_FTR_SECTION - b 4f -END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE) -#ifdef CONFIG_PPC_P7_NAP +#ifdef CONFIG_PPC_P7_NAP /* * Check if thread was in power saving mode. We come here when any * of the following is true: @@ -1128,30 +1125,26 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206) #endif - /* - * Check if we are coming from hypervisor userspace. If yes then we - * continue in host kernel in V mode to deliver the MC event. - */ - rldicl. r11,r12,4,63 /* See if MC hit while in HV mode. */ - beq 5f -4: andi. r11,r12,MSR_PR /* See if coming from user. */ - bne 9f /* continue in V mode if we are. */ - -5: #ifdef CONFIG_KVM_BOOK3S_64_HANDLER -BEGIN_FTR_SECTION /* - * We are coming from kernel context. Check if we are coming from - * guest. if yes, then we can continue. We will fall through - * do_kvm_200->kvmppc_interrupt to deliver the MC event to guest. + * Check if we are coming from guest. If yes, then run the normal + * exception handler which will take the do_kvm_200->kvmppc_interrupt + * branch to deliver the MC event to guest. */ lbz r11,HSTATE_IN_GUEST(r13) cmpwi r11,0 /* Check if coming from guest */ bne 9f /* continue if we are. */ -END_FTR_SECTION_IFSET(CPU_FTR_HVMODE) #endif + + /* + * Check if we are coming from userspace. If yes, then run the normal + * exception handler which will deliver the MC event to this kernel. + */ + andi. r11,r12,MSR_PR /* See if coming from user. */ + bne 9f /* continue in V mode if we are. */ + /* - * At this point we are not sure about what context we come from. + * At this point we are coming from kernel context. * Queue up the MCE event and return from the interrupt. * But before that, check if this is an un-recoverable exception. * If yes, then stay on emergency stack and panic. -- 2.20.1