Commit 18b48d58 authored Sep 17, 2012 by Wen Congyang Committed by Linus Torvalds Sep 17, 2012

memory hotplug: reset pgdat->kswapd to NULL if creating kernel thread fails



If kthread_run() fails, pgdat->kswapd contains errno.  When we stop this
thread, we only check whether pgdat->kswapd is NULL and access it.  If
it contains errno, it will cause page fault.  Reset pgdat->kswapd to
NULL when creating kernel thread fails can avoid this problem.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 6bf61045

mm/vmscan.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -3102,6 +3102,7 @@ int kswapd_run(int nid)
		/* failure at boot is fatal */
		BUG_ON(system_state == SYSTEM_BOOTING);
		printk("Failed to start kswapd on node %d\n",nid);
		pgdat->kswapd = NULL;
		ret = -1;
		}
		return ret;