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| author | Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> | 2021-11-09 13:47:22 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-11-09 22:41:12 +0300 |
| commit | 7607c44c157d343223510c8ffdf7206fdd2a6213 (patch) | |
| tree | 5d583e2d24b462f62bad819bd52c45f50d6d16d9 /block | |
| parent | cb690f5238d71f543f4ce874aa59237cf53a877c (diff) | |
| download | linux-7607c44c157d343223510c8ffdf7206fdd2a6213.tar.xz | |
block: Hold invalidate_lock in BLKDISCARD ioctl
When BLKDISCARD ioctl and data read race, the data read leaves stale
page cache. To avoid the stale page cache, hold invalidate_lock of the
block device file mapping. The stale page cache is observed when
blktests test case block/009 is repeated hundreds of times.
This patch can be applied back to the stable kernel version v5.15.y
with slight patch edit. Rework is required for older stable kernels.
Fixes: 351499a172c0 ("block: Invalidate cache on discard v2")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org # v5.15
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211109104723.835533-2-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/ioctl.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/block/ioctl.c b/block/ioctl.c index d6af0ac97e57..9fa87f64f703 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -113,6 +113,7 @@ static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, uint64_t range[2]; uint64_t start, len; struct request_queue *q = bdev_get_queue(bdev); + struct inode *inode = bdev->bd_inode; int err; if (!(mode & FMODE_WRITE)) @@ -135,12 +136,17 @@ static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, if (start + len > bdev_nr_bytes(bdev)) return -EINVAL; + filemap_invalidate_lock(inode->i_mapping); err = truncate_bdev_range(bdev, mode, start, start + len - 1); if (err) - return err; + goto fail; + + err = blkdev_issue_discard(bdev, start >> 9, len >> 9, + GFP_KERNEL, flags); - return blkdev_issue_discard(bdev, start >> 9, len >> 9, - GFP_KERNEL, flags); +fail: + filemap_invalidate_unlock(inode->i_mapping); + return err; } static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode, |