> v2's not going to make a difference unless you're using uprobes at the > same time.
Not (knowingly) using uprobes. System is installed with a RHEL7 userspace ... but is essentially idle except for my test program. > In the interest of my sanity, can you add something like > BUG_ON(!user_mode_vm(regs)) or the mce_panic equivalent before calling > memory_failure? I don't think that can possibly trip - we can only end up with a recoverable error from a user mode access. But I'll see about adding it anyway > What happens if there's a shared bank but the actual offender has a > higher order than the cpu that finds the error? This test case injects a memory error which is logged in bank1. This bank is shared by the two hyperthreads that are on the same core. The mce_severity() function distinguishes which is the active thread and which the innocent bystander by looking at MCG_STATUS. In the active thread MCG_STATUS.EIPV is 1, in the bystander it is 0. The returned severity is MCE_AR_SEVERITY for the thread that hit the error, MCE_KEEP_SEVERITY for the bystander. So it doesn't matter which thread has the lower order and sees it first. > Is this something I can try under KVM? I don't know if KVM has a way to simulate a machine check event. -Tony
