Commit ac255752 authored Jun 25, 2005 by Shaohua Li Committed by Linus Torvalds Jun 25, 2005

[PATCH] CPU hotplug printk fix

In the cpu hotplug case, per-cpu data possibly isn't initialized even the
system state is 'running'. As the comments say in the original code, some
console drivers assume per-cpu resources have been allocated. radeon fb is
one such driver, which uses kmalloc. After a CPU is down, the per-cpu data
of slab is freed, so the system crashed when printing some info.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 8d783b3e

kernel/printk.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -588,8 +588,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
		log_level_unknown = 1;
		}

		if (!cpu_online(smp_processor_id()) &&
		system_state != SYSTEM_RUNNING) {
		if (!cpu_online(smp_processor_id())) {
		/*
		* Some console drivers may assume that per-cpu resources have
		* been allocated. So don't allow them to be called by this