The driver may sleep under a read rcu lock, and function call path is:
xfs_iget (acquire the lock by rcu_read_lock)
  "goto out_error_or_again" after xfs_iget_cache_hit
    delay
      schedule_timeout_uninterruptible --> may sleep
Meanwhile, the rcu_read_lock will be called twice in this situation.

To fix it, the lock is released before "goto".

Signed-off-by: Jia-Ju Bai <baijiaju1...@163.com>
---
 fs/xfs/xfs_icache.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index f61c84f8..c2a4722 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -600,8 +600,10 @@ struct xfs_inode *
 
        if (ip) {
                error = xfs_iget_cache_hit(pag, ip, ino, flags, lock_flags);
-               if (error)
+               if (error) {
+                       rcu_read_unlock();
                        goto out_error_or_again;
+               }
        } else {
                rcu_read_unlock();
                XFS_STATS_INC(mp, xs_ig_missed);
-- 
1.7.9.5


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