On Tue, 13 Aug 2013 17:50:51 +0400, Vyacheslav Dubeyko wrote: > From: Vyacheslav Dubeyko <[email protected]> > Subject: [PATCH v3 2/2] nilfs2: fix issue with counting number of bio > requests for BIO_EOPNOTSUPP error detection > > This patch fixes the issue with improper counting number of > flying bio requests for BIO_EOPNOTSUPP error detection case. > > The sb_nbio must be incremented exactly the same number of times as > complete() function was called (or will be called) because > nilfs_segbuf_wait() will call wail_for_completion() for the number of > times set to sb_nbio: > > do { > wait_for_completion(&segbuf->sb_bio_event); > } while (--segbuf->sb_nbio > 0); > > Two functions complete() and wait_for_completion() must be called the > same number of times for the same sb_bio_event. Otherwise, > wait_for_completion() will hang or leak. > > Signed-off-by: Vyacheslav Dubeyko <[email protected]> > CC: Ryusuke Konishi <[email protected]>
Acked-by: Ryusuke Konishi <[email protected]> Tested-by: Ryusuke Konishi <[email protected]> I confirmed that this fixes the leak of wait_for_completion() for the BIO_EOPNOTSUPP error detection case. Andrew, please send this upstream along with the companion patch titled "nilfs2: remove double bio_put() in nilfs_end_bio_write() for BIO_EOPNOTSUPP error". Thanks, Ryusuke Konishi > CC: Dan Carpenter <[email protected]> > --- > fs/nilfs2/segbuf.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c > index 5bacf46..2d8be51 100644 > --- a/fs/nilfs2/segbuf.c > +++ b/fs/nilfs2/segbuf.c > @@ -376,12 +376,12 @@ static int nilfs_segbuf_submit_bio(struct > nilfs_segment_buffer *segbuf, > bio->bi_private = segbuf; > bio_get(bio); > submit_bio(mode, bio); > + segbuf->sb_nbio++; > if (bio_flagged(bio, BIO_EOPNOTSUPP)) { > bio_put(bio); > err = -EOPNOTSUPP; > goto failed; > } > - segbuf->sb_nbio++; > bio_put(bio); > > wi->bio = NULL; > -- > 1.7.9.5 > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
