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LU-8685 kernel: jbd2: fix incorrect unlock on j_list_lock
[fs/lustre-release.git] / lustre / kernel_patches / patches / jbd2-fix-j_list_lock-unlock-3.10-rhel7.patch
diff --git a/lustre/kernel_patches/patches/jbd2-fix-j_list_lock-unlock-3.10-rhel7.patch b/lustre/kernel_patches/patches/jbd2-fix-j_list_lock-unlock-3.10-rhel7.patch
new file mode 100644 (file)
index 0000000..8a0a422
--- /dev/null
@@ -0,0 +1,37 @@
+jbd2: fix incorrect unlock on j_list_lock
+
+When 'jh->b_transaction == transaction' (asserted by below)
+
+  J_ASSERT_JH(jh, (jh->b_transaction == transaction || ...
+
+'journal->j_list_lock' will be incorrectly unlocked, since
+the the lock is aquired only at the end of if / else-if
+statements (missing the else case).
+
+This bug has been introduced by an earlier change named
+"jbd2: minimize region locked by j_list_lock in journal_get_create_access()".
+
+Signed-off-by: Taesoo Kim <tsgatesv@gmail.com>
+
+Index: linux-3.10.0-327.36.1.el7/fs/jbd2/transaction.c
+===================================================================
+--- linux-3.10.0-327.36.1.el7.orig/fs/jbd2/transaction.c
++++ linux-3.10.0-327.36.1.el7/fs/jbd2/transaction.c
+@@ -1091,6 +1091,7 @@
+               JBUFFER_TRACE(jh, "file as BJ_Reserved");
+               spin_lock(&journal->j_list_lock);
+               __jbd2_journal_file_buffer(jh, transaction, BJ_Reserved);
++              spin_unlock(&journal->j_list_lock);
+       } else if (jh->b_transaction == journal->j_committing_transaction) {
+               /* first access by this transaction */
+               jh->b_modified = 0;
+@@ -1098,8 +1099,8 @@
+               JBUFFER_TRACE(jh, "set next transaction");
+               spin_lock(&journal->j_list_lock);
+               jh->b_next_transaction = transaction;
++              spin_unlock(&journal->j_list_lock);
+       }
+-      spin_unlock(&journal->j_list_lock);
+       jbd_unlock_bh_state(bh);
+       /*