kernel/linux.git/sound/core/init.c, branch v6.12.80

ALSA: core: add isascii() check to card ID generator

2024-10-03T07:16:58+00:00

The card identifier should contain only safe ASCII characters. The isalnum() returns true also for characters for non-ASCII characters. Link: https://gitlab.freedesktop.org/pipewire/pipewire/-/issues/4135 Link: https://lore.kernel.org/linux-sound/yk3WTvKkwheOon_LzZlJ43PPInz6byYfBzpKkbasww1yzuiMRqn7n6Y8vZcXB-xwFCu_vb8hoNjv7DTNwH5TWjpEuiVsyn9HPCEXqwF4120=@protonmail.com/ Cc: stable@vger.kernel.org Reported-by: Barnabás Pőcze Signed-off-by: Jaroslav Kysela Link: https://patch.msgid.link/20241002194649.1944696-1-perex@perex.cz Signed-off-by: Takashi Iwai

ALSA: control: Rename ctl_files_rwlock to controls_rwlock

2024-08-09T12:24:55+00:00

We'll re-use the existing rwlock for the protection of control list lookup, too, and now rename it to a more generic name. This is a preliminary change, only the rename of the struct field here, no functional changes. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20240809104234.8488-2-tiwai@suse.de

ALSA: core: Remove debugfs at disconnection

2024-05-27T07:28:21+00:00

The card-specific debugfs entries are removed at the last stage of card free phase, and it's performed after synchronization of the closes of all opened fds. This works fine for most cases, but it can be potentially problematic for a hotplug device like USB-audio. Due to the nature of snd_card_free_when_closed(), the card free isn't called immediately after the driver removal for a hotplug device, but it's left until the last fd is closed. It implies that the card debugfs entries also remain. Meanwhile, when a new device is inserted before the last close and the very same card slot is assigned, the driver tries to create the card debugfs root again on the very same path. This conflicts with the remaining entry, and results in the kernel warning such as: debugfs: Directory 'card0' with parent 'sound' already present! with the missing debugfs entry afterwards. For avoiding such conflicts, remove debugfs entries at the device disconnection phase instead. The jack kctl debugfs entries get removed in snd_jack_dev_disconnect() instead of each kctl private_free. Fixes: 2d670ea2bd53 ("ALSA: jack: implement software jack injection via debugfs") Link: https://lore.kernel.org/r/20240524151256.32521-1-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: core: Enable proc module when CONFIG_MODULES=y

2024-05-22T08:10:42+00:00

We used '#ifdef MODULE' for judging whether the system supports the sound module or not, and /proc/asound/modules is created only when '#ifdef MODULE' is true. The check is not really appropriate, though, because the flag means only for the sound core and the drivers are still allowed to be built as modules even if 'MODULE' is not set in sound/core/init.c. For fixing the inconsistency, replace those ifdefs with 'ifdef CONFIG_MODULES'. One place for a NULL module check is rewritten with IS_MODULE(CONFIG_SND) to be more intuitive. It can't be changed to CONFIG_MODULES; otherwise it would hit a WARN_ON() incorrectly. This is a slight behavior change; the modules proc entry appears now no matter whether the sound core is built-in or not as long as modules are enabled on the kernel in general. This can't be avoided due to the nature of kernel builds. Link: https://lore.kernel.org/r/20240520170349.2417900-1-xu.yang_2@nxp.com Signed-off-by: Takashi Iwai Tested-by: Xu Yang Link: https://lore.kernel.org/r/20240522070442.17786-2-tiwai@suse.de

ALSA: core: Fix NULL module pointer assignment at card init

2024-05-22T08:10:39+00:00

The commit 81033c6b584b ("ALSA: core: Warn on empty module") introduced a WARN_ON() for a NULL module pointer passed at snd_card object creation, and it also wraps the code around it with '#ifdef MODULE'. This works in most cases, but the devils are always in details. "MODULE" is defined when the target code (i.e. the sound core) is built as a module; but this doesn't mean that the caller is also built-in or not. Namely, when only the sound core is built-in (CONFIG_SND=y) while the driver is a module (CONFIG_SND_USB_AUDIO=m), the passed module pointer is ignored even if it's non-NULL, and card->module remains as NULL. This would result in the missing module reference up/down at the device open/close, leading to a race with the code execution after the module removal. For addressing the bug, move the assignment of card->module again out of ifdef. The WARN_ON() is still wrapped with ifdef because the module can be really NULL when all sound drivers are built-in. Note that we keep 'ifdef MODULE' for WARN_ON(), otherwise it would lead to a false-positive NULL module check. Admittedly it won't catch perfectly, i.e. no check is performed when CONFIG_SND=y. But, it's no real problem as it's only for debugging, and the condition is pretty rare. Fixes: 81033c6b584b ("ALSA: core: Warn on empty module") Reported-by: Xu Yang Closes: https://lore.kernel.org/r/20240520170349.2417900-1-xu.yang_2@nxp.com Cc: Signed-off-by: Takashi Iwai Tested-by: Xu Yang Link: https://lore.kernel.org/r/20240522070442.17786-1-tiwai@suse.de

ALSA: core: Remove superfluous CONFIG_PM

2024-05-10T13:30:45+00:00

Since the recent code change, the conditional build with CONFIG_PM is calling only snd_power_sync_ref(). As a dummy function is provided for this function, we can get rid of CONFIG_PM gracefully now. Link: https://lore.kernel.org/r/20240510125128.6058-1-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: Fix deadlocks with kctl removals at disconnection

2024-05-10T12:49:32+00:00

In snd_card_disconnect(), we set card->shutdown flag at the beginning, call callbacks and do sync for card->power_ref_sleep waiters at the end. The callback may delete a kctl element, and this can lead to a deadlock when the device was in the suspended state. Namely: * A process waits for the power up at snd_power_ref_and_wait() in snd_ctl_info() or read/write() inside card->controls_rwsem. * The system gets disconnected meanwhile, and the driver tries to delete a kctl via snd_ctl_remove*(); it tries to take card->controls_rwsem again, but this is already locked by the above. Since the sleeper isn't woken up, this deadlocks. An easy fix is to wake up sleepers before processing the driver disconnect callbacks but right after setting the card->shutdown flag. Then all sleepers will abort immediately, and the code flows again. So, basically this patch moves the wait_event() call at the right timing. While we're at it, just to be sure, call wait_event_all() instead of wait_event(), although we don't use exclusive events on this queue for now. Link: https://bugzilla.kernel.org/show_bug.cgi?id=218816 Cc: Reviewed-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20240510101424.6279-1-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: core: Use guard() for locking

2024-02-28T14:01:21+00:00

We can simplify the code gracefully with new guard() macro and co for automatic cleanup of locks. Only the code refactoring, and no functional changes. Signed-off-by: Takashi Iwai Link: https://lore.kernel.org/r/20240227085306.9764-12-tiwai@suse.de

ALSA: core: Use dev_name of card_dev as debugfs directory name

2023-09-12T13:30:37+00:00

There is no need to use temporary string for the debugfs directory name as we can use the device name of the card. This change will also fixes the following compiler warning/error (W=1): sound/core/init.c: In function ‘snd_card_init’: sound/core/init.c:367:28: error: ‘%d’ directive writing between 1 and 10 bytes into a region of size 4 [-Werror=format-overflow=] 367 | sprintf(name, "card%d", idx); | ^~ sound/core/init.c:367:23: note: directive argument in the range [0, 2147483646] 367 | sprintf(name, "card%d", idx); | ^~~~~~~~ sound/core/init.c:367:9: note: ‘sprintf’ output between 6 and 15 bytes into a destination of size 8 367 | sprintf(name, "card%d", idx); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors The idx is guarantied to be less than SNDRV_CARDS (max 256 or 8) by the code in snd_card_init(), however the compiler does not see that. The warnings got brought to light by a recent patch upstream: commit 6d4ab2e97dcf ("extrawarn: enable format and stringop overflow warnings in W=1") Suggested-by: Arnd Bergmann Suggested-by: Takashi Iwai Signed-off-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20230912110113.3166-1-peter.ujfalusi@linux.intel.com Signed-off-by: Takashi Iwai

ALSA: core: Drop snd_device_initialize()

2023-08-17T07:24:33+00:00

Now all users of snd_device_intialize() are gone, let's drop it. Reviewed-by: Jaroslav Kysela Signed-off-by: Curtis Malainey Tested-by: Curtis Malainey Link: https://lore.kernel.org/r/20230816160252.23396-10-tiwai@suse.de Signed-off-by: Takashi Iwai