Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit be07c4ed authored by Duane Griffin's avatar Duane Griffin Committed by Linus Torvalds
Browse files

jbd: abort instead of waiting for nonexistent transactions 

The __log_wait_for_space function sits in a loop checkpointing
transactions until there is sufficient space free in the journal.
However, if there are no transactions to be processed (e.g.  because the
free space calculation is wrong due to a corrupted filesystem) it will
never progress.

Check for space being required when no transactions are outstanding and
abort the journal instead of endlessly looping.

This patch fixes the bug reported by Sami Liedes at:
http://bugzilla.kernel.org/show_bug.cgi?id=10976



Signed-off-by: default avatarDuane Griffin <duaneg@dghda.com>
Tested-by: default avatarSami Liedes <sliedes@cc.hut.fi>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 9f818b4a

fs/jbd/checkpoint.c

+17 −2
Original line number Diff line number Diff line
@@ -127,14 +127,29 @@ void __log_wait_for_space(journal_t *journal) 


		/*

		 * Test again, another process may have checkpointed while we

		 * were waiting for the checkpoint lock

		 * were waiting for the checkpoint lock. If there are no

		 * outstanding transactions there is nothing to checkpoint and

		 * we can't make progress. Abort the journal in this case.

		 */

		spin_lock(&journal->j_state_lock);

		spin_lock(&journal->j_list_lock);

		nblocks = jbd_space_needed(journal);

		if (__log_space_left(journal) < nblocks) {

			int chkpt = journal->j_checkpoint_transactions != NULL;



			spin_unlock(&journal->j_list_lock);

			spin_unlock(&journal->j_state_lock);

			if (chkpt) {

				log_do_checkpoint(journal);

			} else {

				printk(KERN_ERR "%s: no transactions\n",

				       __func__);

				journal_abort(journal, 0);

			}



			spin_lock(&journal->j_state_lock);

		} else {

			spin_unlock(&journal->j_list_lock);

		}

		mutex_unlock(&journal->j_checkpoint_mutex);

	}