lkml.org 
[lkml]   [2014]   [Jan]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 05/14] locks: eliminate BUG() call when there's an unexpected lock on file close
Date
A leftover lock on the list is surely a sign of a problem of some sort,
but it's not necessarily a reason to panic the box. Instead, just log a
warning with some info about the lock, and then delete it like we would
any other lock.

In the event that the filesystem declares a ->lock f_op, we may end up
leaking something, but that's generally preferable to an immediate
panic.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
---
fs/locks.c | 24 ++++++++++++++++++------
1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index 6084f5a..dd30933 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -2281,16 +2281,28 @@ void locks_remove_flock(struct file *filp)

while ((fl = *before) != NULL) {
if (fl->fl_file == filp) {
- if (IS_FLOCK(fl)) {
- locks_delete_lock(before);
- continue;
- }
if (IS_LEASE(fl)) {
lease_modify(before, F_UNLCK);
continue;
}
- /* What? */
- BUG();
+
+ /*
+ * There's a leftover lock on the list of a type that
+ * we didn't expect to see. Most likely a classic
+ * POSIX lock that ended up not getting released
+ * properly, or that raced onto the list somehow. Log
+ * some info about it and then just remove it from
+ * the list.
+ */
+ WARN(!IS_FLOCK(fl),
+ "leftover lock: dev=%u:%u ino=%lu type=%hhd flags=0x%x start=%lld end=%lld\n",
+ MAJOR(inode->i_sb->s_dev),
+ MINOR(inode->i_sb->s_dev), inode->i_ino,
+ fl->fl_type, fl->fl_flags,
+ fl->fl_start, fl->fl_end);
+
+ locks_delete_lock(before);
+ continue;
}
before = &fl->fl_next;
}
--
1.8.4.2


\
 
 \ /
  Last update: 2014-01-09 16:01    [W:0.109 / U:0.140 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site