From 47c89922d3af8dc01ad77e34a61e5ceae2d7a11c Mon Sep 17 00:00:00 2001 From: Marcin Jurkowski Date: Sat, 2 Mar 2013 14:50:15 +0100 Subject: w1: fix oops when w1_search is called from netlink connector commit 9d1817cab2f030f6af360e961cc69bb1da8ad765 upstream. On Sat, Mar 02, 2013 at 10:45:10AM +0100, Sven Geggus wrote: > This is the bad commit I found doing git bisect: > 04f482faf50535229a5a5c8d629cf963899f857c is the first bad commit > commit 04f482faf50535229a5a5c8d629cf963899f857c > Author: Patrick McHardy > Date: Mon Mar 28 08:39:36 2011 +0000 Good job. I was too lazy to bisect for bad commit;) Reading the code I found problematic kthread_should_stop call from netlink connector which causes the oops. After applying a patch, I've been testing owfs+w1 setup for nearly two days and it seems to work very reliable (no hangs, no memleaks etc). More detailed description and possible fix is given below: Function w1_search can be called from either kthread or netlink callback. While the former works fine, the latter causes oops due to kthread_should_stop invocation. This patch adds a check if w1_search is serving netlink command, skipping kthread_should_stop invocation if so. Signed-off-by: Marcin Jurkowski Acked-by: Evgeniy Polyakov Cc: Josh Boyer Tested-by: Sven Geggus Signed-off-by: Greg Kroah-Hartman --- drivers/w1/w1.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/w1') diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 10606c8..cbff966 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -918,7 +918,8 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb tmp64 = (triplet_ret >> 2); rn |= (tmp64 << i); - if (kthread_should_stop()) { + /* ensure we're called from kthread and not by netlink callback */ + if (!dev->priv && kthread_should_stop()) { dev_dbg(&dev->dev, "Abort w1_search\n"); return; } -- cgit v1.1