diff --git a/arch/powerpc/kernel/mce_power.c b/arch/powerpc/kernel/mce_power.c index b76ca198e09c..f523125b9d34 100644 --- a/arch/powerpc/kernel/mce_power.c +++ b/arch/powerpc/kernel/mce_power.c @@ -624,5 +624,18 @@ long __machine_check_early_realmode_p8(struct pt_regs *regs) long __machine_check_early_realmode_p9(struct pt_regs *regs) { + /* + * On POWER9 DD2.1 and below, it's possible to get a machine check + * caused by a paste instruction where only DSISR bit 30 is set. This + * will result in the MCE handler seeing an unknown event and the kernel + * crashing. An MCE that occurs like this is spurious, so we don't need + * to do anything in terms of servicing it. If there is something that + * needs to be serviced, the CPU will raise the MCE again with the + * correct DSISR so that it can be serviced properly. So detect this + * case and mark it as handled. + */ + if (SRR1_MC_LOADSTORE(regs->msr) && regs->dsisr == 0x40000000) + return 1; + return mce_handle_error(regs, mce_p9_derror_table, mce_p9_ierror_table); }