[PATCH 2/4] jbd: relocate assert after state lock in journal_commit_transaction()

From: Paul Gortmaker
Date: Thu Aug 01 2013 - 15:02:26 EST


Backport of jbd2 commit 3ca841c106fd6cd2c942985977a5d126434a8dd6
("jbd2: relocate assert after state lock in journal_commit_transaction()")

Quoting that commit:
---------------
The state lock is taken after we are doing an assert on the state
value, not before. So we might in fact be doing an assert on a
transient value. Ensure the state check is within the scope of
the state lock being taken.
---------------

Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
fs/jbd/commit.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c
index 11bb11f..bb217dc 100644
--- a/fs/jbd/commit.c
+++ b/fs/jbd/commit.c
@@ -340,13 +340,13 @@ void journal_commit_transaction(journal_t *journal)
J_ASSERT(journal->j_committing_transaction == NULL);

commit_transaction = journal->j_running_transaction;
- J_ASSERT(commit_transaction->t_state == T_RUNNING);

trace_jbd_start_commit(journal, commit_transaction);
jbd_debug(1, "JBD: starting commit of transaction %d\n",
commit_transaction->t_tid);

spin_lock(&journal->j_state_lock);
+ J_ASSERT(commit_transaction->t_state == T_RUNNING);
commit_transaction->t_state = T_LOCKED;

trace_jbd_commit_locking(journal, commit_transaction);
--
1.8.1.2

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