Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
x86: Ignore NMIs that come in during early boot
Don Zickus reports: A customer generated an external NMI using their iLO to test kdump worked. Unfortunately, the machine hung. Disabling the nmi_watchdog made things work. I speculated the external NMI fired, caused the machine to panic (as expected) and the perf NMI from the watchdog came in and was latched. My guess was this somehow caused the hang. ---- It appears that the latched NMI stays latched until the early page table generation on 64 bits, which causes exceptions to happen which end in IRET, which re-enable NMI. Therefore, ignore NMIs that come in during early execution, until we have proper exception handling. Reported-and-tested-by: Don Zickus <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: H. Peter Anvin <[email protected]> Cc: <[email protected]> # v3.5+, older with some backport effort
- Loading branch information