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| author | Ming Lei <ming.lei@canonical.com> | 2016-03-12 09:29:40 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-12 07:33:39 -0700 |
| commit | bdb486fac4c1cc167fe9017e3fd3bc5b88090d6e (patch) | |
| tree | 0471a9d51bcbf40466db502b916ca64858f4cf3c | |
| parent | ea43a45d9885879257d985ff139cbb999ff3e830 (diff) | |
| download | lwn-bdb486fac4c1cc167fe9017e3fd3bc5b88090d6e.tar.gz lwn-bdb486fac4c1cc167fe9017e3fd3bc5b88090d6e.zip | |
md: multipath: don't hardcopy bio in .make_request path
commit fafcde3ac1a418688a734365203a12483b83907a upstream.
Inside multipath_make_request(), multipath maps the incoming
bio into low level device's bio, but it is totally wrong to
copy the bio into mapped bio via '*mapped_bio = *bio'. For
example, .__bi_remaining is kept in the copy, especially if
the incoming bio is chained to via bio splitting, so .bi_end_io
can't be called for the mapped bio at all in the completing path
in this kind of situation.
This patch fixes the issue by using clone style.
Reported-and-tested-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/md/multipath.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c index 0a72ab6e6c20..dd483bb2e111 100644 --- a/drivers/md/multipath.c +++ b/drivers/md/multipath.c @@ -129,7 +129,9 @@ static void multipath_make_request(struct mddev *mddev, struct bio * bio) } multipath = conf->multipaths + mp_bh->path; - mp_bh->bio = *bio; + bio_init(&mp_bh->bio); + __bio_clone_fast(&mp_bh->bio, bio); + mp_bh->bio.bi_iter.bi_sector += multipath->rdev->data_offset; mp_bh->bio.bi_bdev = multipath->rdev->bdev; mp_bh->bio.bi_rw |= REQ_FAILFAST_TRANSPORT; |