Re: [PATCH 00/11] ALSA: Make control API taking controls_rwsem consistently

[Takashi Iwai <tiwai@suse.de>]

On Tue, 18 Jul 2023 16:12:53 +0200,
Takashi Iwai wrote:
> 
> A few ALSA control API helpers like snd_ctl_rename(), snd_ctl_remove()
> and snd_ctl_find_*() suppose the callers taking card->controls_rwsem.
> But it's error-prone and fragile.  This patch set tries to change
> those API functions to take the card->controls>rwsem internally by
> themselves, so that the drivers don't need to take care of lockings.
> 
> After applying this patch set, only a couple of places still touch
> card->controls_rwsem (which are OK-ish as they need for traversing the
> control linked list).
> 
> 
> Takashi
> 
> ===
> 
> Takashi Iwai (11):
>   ALSA: control: Take card->controls_rwsem in snd_ctl_rename()
>   staging: greybus: audio_helper: Use snd_ctl_remove_id()
>   ASoC: atmel: mchp-pdmc: Use snd_ctl_remove_id()
>   ALSA: control: Take controls_rwsem lock in snd_ctl_remove()
>   ALSA: control: Add lockdep warning to internal functions
>   ASoC: sigmadsp: Simplify with snd_ctl_activate_id()
>   staging: greybus: Avoid abusing controls_rwsem
>   ALSA: control: Make snd_ctl_find_id() argument const
>   ALSA: control: Introduce unlocked version for snd_ctl_find_*() helpers
>   ALSA: control: Take lock in snd_ctl_find_id() and snd_ctl_find_numid()
>   ALSA: emu10k1: Go back and simplify with snd_ctl_find_id()

Now all merged.  The branch is based on 6.5-rc2, and tagged as
ctl-lock-fixes-6.6 so that other branch can merge this if needed.


Takashi