diff options
| author | Shaohua Li <shaohua.li@intel.com> | 2011-06-27 09:03:47 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-07-08 23:15:24 -0700 |
| commit | 3ad80528ba9a8d2e69aba2e110dc875765196bac (patch) | |
| tree | b839f681ae570d593735e38b83f5145b3421245f | |
| parent | b1ad9117b692986f2fc0d2d1b3f6f56b696d38cc (diff) | |
cfq-iosched: fix a rcu warning
commit 3181faa85bda3dc3f5e630a1846526c9caaa38e3 upstream.
I got a rcu warnning at boot. the ioc->ioc_data is rcu_deferenced, but
doesn't hold rcu_read_lock.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | block/cfq-iosched.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index d31adc2c9513..c382d7268c3e 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -2704,11 +2704,14 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd, smp_wmb(); cic->key = cfqd_dead_key(cfqd); + rcu_read_lock(); if (rcu_dereference(ioc->ioc_data) == cic) { + rcu_read_unlock(); spin_lock(&ioc->lock); rcu_assign_pointer(ioc->ioc_data, NULL); spin_unlock(&ioc->lock); - } + } else + rcu_read_unlock(); if (cic->cfqq[BLK_RW_ASYNC]) { cfq_exit_cfqq(cfqd, cic->cfqq[BLK_RW_ASYNC]); |