[PATCH] ext3/4: fix J_ASSERT(transaction->t_updates > 0) in journal_stop()

A disk generated some I/O error, after it, I hitted
J_ASSERT(transaction->t_updates > 0) in journal_stop().

It seems to happened on ext3_truncate() path from stack trace. Then,
maybe the following case may trigger J_ASSERT(transaction->t_updates > 0).

ext3_truncate()
    -> ext3_free_branches()
        -> ext3_journal_test_restart()
	    -> ext3_journal_restart()
                -> journal_restart()
                transaction->t_updates--;
                /* another process aborted journal */
                    -> start_this_handle()
		    returns -EROFS without transaction->t_updates++;

    -> ext3_journal_stop()
        -> journal_stop()
	J_ASSERT(transaction->t_updates > 0)

If journal was aborted in middle of journal_restart(), ext3_truncate()
may trigger J_ASSERT().

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index e1b3c8a..d5c6304 100644 (file)
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -1314,13 +1314,14 @@ int journal_stop(handle_t *handle)
        int old_handle_count, err;
        pid_t pid;
 
-       J_ASSERT(transaction->t_updates > 0);
        J_ASSERT(journal_current_handle() == handle);
 
        if (is_handle_aborted(handle))
                err = -EIO;
-       else
+       else {
+               J_ASSERT(transaction->t_updates > 0);
                err = 0;
+       }
 
        if (--handle->h_ref > 0) {
                jbd_debug(4, "h_ref %d -> %d\n", handle->h_ref + 1,

diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 149957b..b6cf2be 100644 (file)
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1314,13 +1314,14 @@ int jbd2_journal_stop(handle_t *handle)
        int old_handle_count, err;
        pid_t pid;
 
-       J_ASSERT(transaction->t_updates > 0);
        J_ASSERT(journal_current_handle() == handle);
 
        if (is_handle_aborted(handle))
                err = -EIO;
-       else
+       else {
+               J_ASSERT(transaction->t_updates > 0);
                err = 0;
+       }
 
        if (--handle->h_ref > 0) {
                jbd_debug(4, "h_ref %d -> %d\n", handle->h_ref + 1,