diff options
| author | Takashi Iwai <tiwai@suse.de> | 2022-10-11 10:01:46 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-10-26 14:25:06 +0300 |
| commit | ef1658bc482c4ea8d5c55735fd8f4558d2bb5948 (patch) | |
| tree | bf20b70f67cec4ce9467b1944838566e13f71288 /sound/core | |
| parent | 026fcb6336d6e2917ec375964a36c72183d8fd21 (diff) | |
| download | linux-ef1658bc482c4ea8d5c55735fd8f4558d2bb5948.tar.xz | |
ALSA: rawmidi: Drop register_mutex in snd_rawmidi_free()
commit a70aef7982b012e86dfd39fbb235e76a21ae778a upstream.
The register_mutex taken around the dev_unregister callback call in
snd_rawmidi_free() may potentially lead to a mutex deadlock, when OSS
emulation and a hot unplug are involved.
Since the mutex doesn't protect the actual race (as the registration
itself is already protected by another means), let's drop it.
Link: https://lore.kernel.org/r/CAB7eexJP7w1B0mVgDF0dQ+gWor7UdkiwPczmL7pn91xx8xpzOA@mail.gmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20221011070147.7611-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'sound/core')
| -rw-r--r-- | sound/core/rawmidi.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c index 257ad5206240..0d91143eb464 100644 --- a/sound/core/rawmidi.c +++ b/sound/core/rawmidi.c @@ -1736,10 +1736,8 @@ static int snd_rawmidi_free(struct snd_rawmidi *rmidi) snd_info_free_entry(rmidi->proc_entry); rmidi->proc_entry = NULL; - mutex_lock(®ister_mutex); if (rmidi->ops && rmidi->ops->dev_unregister) rmidi->ops->dev_unregister(rmidi); - mutex_unlock(®ister_mutex); snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]); snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]); |