raid5: fix a race of stripe count check
authorShaohua Li <shli@kernel.org>
Tue, 15 Apr 2014 01:12:54 +0000 (09:12 +0800)
committerNeilBrown <neilb@suse.de>
Thu, 17 Apr 2014 07:05:28 +0000 (17:05 +1000)
commitc7a6d35e463caacab08ca0333bdec5b8bdce8bbb
treebf4abac968402f11ba3d26e238ab62173f2bb23a
parente240c1839d11152b0355442f8ac6d2d2d921be36
raid5: fix a race of stripe count check

I hit another BUG_ON with e240c1839d11152b0355442. In __get_priority_stripe(),
stripe count equals to 0 initially. Between atomic_inc and BUG_ON,
get_active_stripe() finds the stripe. So the stripe count isn't 1 any more.

V2: keeps the BUG_ON suggested by Neil.

Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
drivers/md/raid5.c