diff options
| author | Takashi Iwai <tiwai@suse.de> | 2017-11-06 20:16:50 +0100 |
|---|---|---|
| committer | Sasha Levin <alexander.levin@verizon.com> | 2017-12-06 21:20:01 -0500 |
| commit | 1437d2f78eb1aac418b549915fa39adb065ba10b (patch) | |
| tree | bc8ed6f728a0df970dadc3ef709507fab0e62fc5 /include | |
| parent | b975b771930e4931a11f9d6fe7d9d54fd884c8ea (diff) | |
ALSA: seq: Avoid invalid lockdep class warning
[ Upstream commit 3510c7aa069aa83a2de6dab2b41401a198317bdc ]
The recent fix for adding rwsem nesting annotation was using the given
"hop" argument as the lock subclass key. Although the idea itself
works, it may trigger a kernel warning like:
BUG: looking up invalid subclass: 8
....
since the lockdep has a smaller number of subclasses (8) than we
currently allow for the hops there (10).
The current definition is merely a sanity check for avoiding the too
deep delivery paths, and the 8 hops are already enough. So, as a
quick fix, just follow the max hops as same as the max lockdep
subclasses.
Fixes: 1f20f9ff57ca ("ALSA: seq: Fix nested rwsem annotation for lockdep splat")
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/sound/seq_kernel.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/include/sound/seq_kernel.h b/include/sound/seq_kernel.h index feb58d455560..4b9ee3009aa0 100644 --- a/include/sound/seq_kernel.h +++ b/include/sound/seq_kernel.h @@ -49,7 +49,8 @@ typedef union snd_seq_timestamp snd_seq_timestamp_t; #define SNDRV_SEQ_DEFAULT_CLIENT_EVENTS 200 /* max delivery path length */ -#define SNDRV_SEQ_MAX_HOPS 10 +/* NOTE: this shouldn't be greater than MAX_LOCKDEP_SUBCLASSES */ +#define SNDRV_SEQ_MAX_HOPS 8 /* max size of event size */ #define SNDRV_SEQ_MAX_EVENT_LEN 0x3fffffff |