mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-16 16:54:20 +08:00
7c5c92ed56
I have a busy ppc64le KVM box where guests sometimes hit the infamous "kernel BUG at kernel/smpboot.c:134!" issue during boot: BUG_ON(td->cpu != smp_processor_id()); Basically a per CPU hotplug thread scheduled on the wrong CPU. The oops output confirms it: CPU: 0 Comm: watchdog/130 The problem is that we aren't ensuring the CPU active and online bits are set before allowing the master to continue on. The master unparks the secondary CPUs kthreads and the scheduler looks for a CPU to run on. It calls select_task_rq and realises the suggested CPU is not in the cpus_allowed mask. It then ends up in select_fallback_rq, and since the active and online bits aren't set we choose some other CPU to run on. Cc: stable@vger.kernel.org Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> |
||
|---|---|---|
| .. | ||
| boot | ||
| configs | ||
| crypto | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| perf | ||
| platforms | ||
| sysdev | ||
| xmon | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| relocs_check.pl | ||