Re: Assertion failure in journal_flush()

Stephen C. Tweedie
2002-01-07T19:39:34Z

Hi,

On Mon, Jan 07, 2002 at 05:24:36PM +0100, Carsten Otte
wrote:
>
> We encountered a reproduceable problem with ext3:
> When issuing a FIBMAP ioctl for a block written right before while
> the FS is under high load (RH build universe), the assertion
> !journal->j_running_transaction fails at the bottom of journal_flush()
> in fs/jbd/journal.c.
> We encountered this problem with the arch=s390x (64 bit big endian)
> bootloader zipl, I'll try to reproduce it with 2.4.latest on arch=i386.
> I'll try
> to create a stack backtrace as well by inserting a BUG();.

Does the patch below fix it?  There was one path through the
transaction startup code where we could drop the journal lock without
retesting the barrier which protects that FIBMAP special case.

Cheers,
 Stephen

Index: fs/jbd/transaction.c
==================================================================RCS file:
/cvsroot/gkernel/ext3/fs/jbd/transaction.c,v
retrieving revision 1.64.2.5
retrieving revision 1.64.2.6
diff -c -r1.64.2.5 -r1.64.2.6
*** fs/jbd/transaction.c	2001/11/18 03:46:45	1.64.2.5
--- fs/jbd/transaction.c	2002/01/07 19:33:24	1.64.2.6
***************
*** 97,102 ****
--- 97,104 ----

  	lock_journal(journal);

+ repeat_locked:
+
  	if (is_journal_aborted(journal) ||
  	    (journal->j_errno != 0 && !(journal->j_flags &
JFS_ACK_ERR))) {
  		unlock_journal(journal);
***************
*** 110,116 ****
  		goto repeat;
  	}

- repeat_locked:
  	if (!journal->j_running_transaction)
  		get_transaction(journal, 0);
  	/* @@@ Error? */
--- 112,117 ----