diff options
| author | Jan Kara <[email protected]> | 2017-03-23 01:37:00 +0100 |
|---|---|---|
| committer | Jens Axboe <[email protected]> | 2017-03-22 20:11:33 -0600 |
| commit | f759741d9d913eb57784a94b9bca78b376fc26a9 (patch) | |
| tree | 19832434e2c4c1db34bceee048f422b910300686 /include/linux | |
| parent | b1c51afc00f164457e126dcfc946fdd563948d26 (diff) | |
block: Fix oops in locked_inode_to_wb_and_lock_list()
When block device is closed, we call inode_detach_wb() in __blkdev_put()
which sets inode->i_wb to NULL. That is contrary to expectations that
inode->i_wb stays valid once set during the whole inode's lifetime and
leads to oops in wb_get() in locked_inode_to_wb_and_lock_list() because
inode_to_wb() returned NULL.
The reason why we called inode_detach_wb() is not valid anymore though.
BDI is guaranteed to stay along until we call bdi_put() from
bdev_evict_inode() so we can postpone calling inode_detach_wb() to that
moment.
Also add a warning to catch if someone uses inode_detach_wb() in a
dangerous way.
Reported-by: Thiago Jung Bauermann <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Signed-off-by: Jan Kara <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/writeback.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/writeback.h b/include/linux/writeback.h index a3c0cbd7c888..d5815794416c 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -237,6 +237,7 @@ static inline void inode_attach_wb(struct inode *inode, struct page *page) static inline void inode_detach_wb(struct inode *inode) { if (inode->i_wb) { + WARN_ON_ONCE(!(inode->i_state & I_CLEAR)); wb_put(inode->i_wb); inode->i_wb = NULL; } |