The OSS emulation in synth-emux helper has a potential AB/BA deadlock
at the simultaneous closing and opening:
close ->
snd_seq_release() ->
sne_seq_free_client() ->
snd_seq_delete_all_ports(): takes client->ports_mutex ->
port_delete() ->
snd_emux_unuse(): takes emux->register_mutex
open ->
snd_seq_oss_open() ->
snd_emux_open_seq_oss(): takes emux->register_mutex ->
snd_seq_event_port_attach() ->
snd_seq_create_port(): takes client->ports_mutex
This patch addresses the deadlock by reducing the rance taking
emux->register_mutex in snd_emux_open_seq_oss(). The lock is needed
for the refcount handling, so move it locally. The calls in
emux_seq.c are already with the mutex, thus they are replaced with the
version without mutex lock/unlock.
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The emux-synth driver has a possible AB/BA mutex deadlock at unloading
the emu10k1 driver:
snd_emux_free() ->
snd_emux_detach_seq(): mutex_lock(&emu->register_mutex) ->
snd_seq_delete_kernel_client() ->
snd_seq_free_client(): mutex_lock(®ister_mutex)
snd_seq_release() ->
snd_seq_free_client(): mutex_lock(®ister_mutex) ->
snd_seq_delete_all_ports() ->
snd_emux_unuse(): mutex_lock(&emu->register_mutex)
Basically snd_emux_detach_seq() doesn't need a protection of
emu->register_mutex as it's already being unregistered. So, we can
get rid of this for avoiding the deadlock.
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Lots of sound drivers were getting module.h via the implicit presence
of it in <linux/device.h> but we are going to clean that up. So
fix up those users now.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Kill snd_assert() in other places, either removed or replaced with
if () with snd_BUG_ON().
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Add four new information flags SNDRV_SEQ_PORT_TYPE_HARDWARE, _SOFTWARE,
_SYNTHESIZER, _PORT for sequencer ports. This makes it easier for apps
like Rosegarden to make policy decisions based on the port type.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Fix the port information about non-MIDI messages that had wrong values
for some OPL3 and EmuX ports.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
All users of snd_seq_create_kernel_client() have to set the client name
anyway, so we can just pass the name as parameter. This relieves us
from having to muck around with a struct snd_seq_client_info in these
cases.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
The fields of struct snd_seq_client_callback either aren't used or are
always set to the same value, so we can get rid of it altogether.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Takashi Iwai