linux.git/sound/synth, branch v6.8

ALSA: emu10k1: fix synthesizer pitch for E-MU cards at 44.1 kHz

2023-06-13T05:42:08+00:00

This is only a very partial fix - the frequency-dependent envelope & LFO
register values aren't adjusted.

But I'm not sure they were even correct at 48 kHz to start with, as most
of them are precalculated by common code which assumes an EMU8K-specific
44.1 kHz word clock, and it seems somewhat unlikely that the hardware's
register interpretation was adjusted to compensate for the different
word clock.

In any case I'm not going to spend time on fixing that, as this code is
unlikely to be actually used by anyone today.

Signed-off-by: Oswald Buddenhagen 
Link: https://lore.kernel.org/r/20230612191325.1315854-6-oswald.buddenhagen@gmx.de
Signed-off-by: Takashi Iwai

ALSA: emux: Avoid potential array out-of-bound in snd_emux_xg_control()

2023-02-07T13:32:33+00:00

snd_emux_xg_control() can be called with an argument 'param' greater
than size of 'control' array. It may lead to accessing 'control'
array at a wrong index.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Artemii Karasev 
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: 
Link: https://lore.kernel.org/r/20230207132026.2870-1-karasev@ispras.ru
Signed-off-by: Takashi Iwai

treewide: Convert del_timer() to timer_shutdown()

2022-12-25T21:38:09+00:00

Due to several bugs caused by timers being re-armed after they are
shutdown and just before they are freed, a new state of timers was added
called "shutdown".  After a timer is set to this state, then it can no
longer be re-armed.

The following script was run to find all the trivial locations where
del_timer() or del_timer_sync() is called in the same function that the
object holding the timer is freed.  It also ignores any locations where
the timer->function is modified between the del_timer*() and the free(),
as that is not considered a "trivial" case.

This was created by using a coccinelle script and the following
commands:

    $ cat timer.cocci
    @@
    expression ptr, slab;
    identifier timer, rfield;
    @@
    (
    -       del_timer(&ptr->timer);
    +       timer_shutdown(&ptr->timer);
    |
    -       del_timer_sync(&ptr->timer);
    +       timer_shutdown_sync(&ptr->timer);
    )
      ... when strict
          when != ptr->timer
    (
            kfree_rcu(ptr, rfield);
    |
            kmem_cache_free(slab, ptr);
    |
            kfree(ptr);
    )

    $ spatch timer.cocci . > /tmp/t.patch
    $ patch -p1 < /tmp/t.patch

Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/
Signed-off-by: Steven Rostedt (Google) 
Acked-by: Pavel Machek  [ LED ]
Acked-by: Kalle Valo  [ wireless ]
Acked-by: Paolo Abeni  [ networking ]
Signed-off-by: Linus Torvalds

ALSA: Use del_timer_sync() before freeing timer

2022-10-27T06:42:08+00:00

The current code for freeing the emux timer is extremely dangerous:

  CPU0				CPU1
  ----				----
snd_emux_timer_callback()
			    snd_emux_free()
			      spin_lock(&emu->voice_lock)
			      del_timer(&emu->tlist); <-- returns immediately
			      spin_unlock(&emu->voice_lock);
			      [..]
			      kfree(emu);

  spin_lock(&emu->voice_lock);

 [BOOM!]

Instead just use del_timer_sync() which will wait for the timer to finish
before continuing. No need to check if the timer is active or not when
doing so.

This doesn't fix the race of a possible re-arming of the timer, but at
least it won't use the data that has just been freed.

[ Fixed unused variable warning by tiwai ]

Cc: stable@vger.kernel.org
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Steven Rostedt (Google) 
Reviewed-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20221026231236.6834b551@gandalf.local.home
Signed-off-by: Takashi Iwai

ALSA: synth: missing check for possible NULL after the call to kstrdup

2021-11-09T06:18:50+00:00

If kcalloc() return NULL due to memory starvation, it is possible for
kstrdup() to return NULL in similar case. So add null check after the call
to kstrdup() is made.

[ minor coding-style fix by tiwai ]

Signed-off-by: Austin Kim 
Cc: 
Link: https://lore.kernel.org/r/20211109003742.GA5423@raspberrypi
Signed-off-by: Takashi Iwai

ALSA: emux: fix spelling mistakes

2021-07-05T17:34:22+00:00

Fix some spelling mistakes as follows:
sensitivies ==> sensitivities
pararameters ==> parameters
approxmimation ==> approximation
silet ==> silent

Signed-off-by: gushengxian 
Link: https://lore.kernel.org/r/20210705125001.665734-1-gushengxian507419@gmail.com
Signed-off-by: Takashi Iwai

ALSA: synth: Fix assignment in if condition

2021-06-09T15:30:35+00:00

EMUx synth driver code contains lots of assignments in if condition,
which is a bad coding style that may confuse readers and occasionally
lead to bugs.

This patch is merely for coding-style fixes, no functional changes.

Link: https://lore.kernel.org/r/20210608140540.17885-64-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: emux: More constifications

2020-01-05T15:14:46+00:00

Apply const prefix to each possible place: the MIDI data definitions,
the static tables for volume parameters, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-22-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: oss: Constify snd_seq_oss_callback definitions

2020-01-03T08:24:41+00:00

The snd_seq_oss_callback items are just copied to another struct
as-is, hence they can be declared as const.

There should be no functional changes by this patch.

Link: https://lore.kernel.org/r/20200103081714.9560-53-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: seq: Constify struct snd_midi_op

2020-01-03T08:24:19+00:00

Change the argument of snd_midi_process_event() to receive a const
snd_midi_op pointer and its callers respectively.  This allows further
optimizations.

There should be no functional changes by this patch.

Link: https://lore.kernel.org/r/20200103081714.9560-30-tiwai@suse.de
Signed-off-by: Takashi Iwai