mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-02 07:04:24 +00:00
5dad4ba68a
It is possible for all CPUs to miss the pending cpumask becoming clear, and then nobody resetting it, which will cause the lockup detector to stop working. It will eventually expire, but watchdog_smp_panic will avoid doing anything if the pending mask is clear and it will never be reset. Order the cpumask clear vs the subsequent test to close this race. Add an extra check for an empty pending mask when the watchdog fires and finds its bit still clear, to try to catch any other possible races or bugs here and keep the watchdog working. The extra test in arch_touch_nmi_watchdog is required to prevent the new warning from firing off. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Debugged-by: Laurent Dufour <ldufour@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211110025056.2084347-2-npiggin@gmail.com |
||
|---|---|---|
| .. | ||
| alpha | ||
| arc | ||
| arm | ||
| arm64 | ||
| csky | ||
| h8300 | ||
| hexagon | ||
| ia64 | ||
| m68k | ||
| microblaze | ||
| mips | ||
| nds32 | ||
| nios2 | ||
| openrisc | ||
| parisc | ||
| powerpc | ||
| riscv | ||
| s390 | ||
| sh | ||
| sparc | ||
| um | ||
| x86 | ||
| xtensa | ||
| .gitignore | ||
| Kconfig | ||