If, due to bugs elsewhere, we get into unregister_cpu_online() with a CPU that isn't marked hotpluggable, we can emit a warning and return an appropriate error instead of crashing.
Signed-off-by: Nathan Lynch <nath...@linux.ibm.com> Reviewed-by: Daniel Henrique Barboza <danielhb...@gmail.com> --- arch/powerpc/kernel/sysfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c index defecb3b1b15..08d8072d6e7a 100644 --- a/arch/powerpc/kernel/sysfs.c +++ b/arch/powerpc/kernel/sysfs.c @@ -928,7 +928,8 @@ static int unregister_cpu_online(unsigned int cpu) struct device_attribute *attrs, *pmc_attrs; int i, nattrs; - BUG_ON(!c->hotpluggable); + if (WARN_RATELIMIT(!c->hotpluggable, "cpu %d can't be offlined\n", cpu)) + return -EBUSY; #ifdef CONFIG_PPC64 if (cpu_has_feature(CPU_FTR_SMT)) -- 2.31.1