4.2-stable review patch. If anyone has any objections, please let me know.
------------------ From: Ryan Ding <[email protected]> commit aa1057b3dec478b20c77bad07442318ae36d893c upstream. ocfs2_file_write_iter() is usng the wrong return value ('written'). This will cause ocfs2_rw_unlock() be called both in write_iter & end_io, triggering a BUG_ON. This issue was introduced by commit 7da839c47589 ("ocfs2: use __generic_file_write_iter()"). Orabug: 21612107 Fixes: 7da839c47589 ("ocfs2: use __generic_file_write_iter()") Signed-off-by: Ryan Ding <[email protected]> Reviewed-by: Junxiao Bi <[email protected]> Cc: Al Viro <[email protected]> Cc: Mark Fasheh <[email protected]> Cc: Joel Becker <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/ocfs2/file.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2372,6 +2372,20 @@ relock: /* buffered aio wouldn't have proper lock coverage today */ BUG_ON(written == -EIOCBQUEUED && !(iocb->ki_flags & IOCB_DIRECT)); + /* + * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io + * function pointer which is called when o_direct io completes so that + * it can unlock our rw lock. + * Unfortunately there are error cases which call end_io and others + * that don't. so we don't have to unlock the rw_lock if either an + * async dio is going to do it in the future or an end_io after an + * error has already done it. + */ + if ((written == -EIOCBQUEUED) || (!ocfs2_iocb_is_rw_locked(iocb))) { + rw_level = -1; + unaligned_dio = 0; + } + if (unlikely(written <= 0)) goto no_sync; @@ -2396,20 +2410,6 @@ relock: } no_sync: - /* - * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io - * function pointer which is called when o_direct io completes so that - * it can unlock our rw lock. - * Unfortunately there are error cases which call end_io and others - * that don't. so we don't have to unlock the rw_lock if either an - * async dio is going to do it in the future or an end_io after an - * error has already done it. - */ - if ((ret == -EIOCBQUEUED) || (!ocfs2_iocb_is_rw_locked(iocb))) { - rw_level = -1; - unaligned_dio = 0; - } - if (unaligned_dio) { ocfs2_iocb_clear_unaligned_aio(iocb); mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
