From: "Duane Griffin" Subject: [PATCH] jbd: abort instead of waiting for nonexistent transactions Date: Tue, 5 Aug 2008 00:51:34 +0100 Message-ID: <1217893895-29165-1-git-send-email-duaneg@dghda.com> Cc: akpm@linux-foundation.org, sct@redhat.com, linux-ext4@vger.kernel.org, Sami Liedes , Duane Griffin To: linux-kernel@vger.kernel.org Return-path: Received: from kumera.dghda.com ([80.68.90.171]:2551 "EHLO kumera.dghda.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756364AbYHDXvj (ORCPT ); Mon, 4 Aug 2008 19:51:39 -0400 Sender: linux-ext4-owner@vger.kernel.org List-ID: 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: Duane Griffin Tested-by: Sami Liedes --- diff --git a/fs/jbd/checkpoint.c b/fs/jbd/checkpoint.c index a5432bb..9fac177 100644 --- a/fs/jbd/checkpoint.c +++ b/fs/jbd/checkpoint.c @@ -126,14 +126,29 @@ 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); - log_do_checkpoint(journal); + 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); }