mirror of
https://github.com/torvalds/linux.git
synced 2024-12-28 22:02:28 +00:00
1e850beea2
The standard programming model of a PCM sound driver is to process snd_pcm_period_elapsed() from an interrupt handler. When a running stream is stopped, PCM core calls the trigger-STOP PCM ops, sets the stream state to SETUP, and moves on to the next step. This is performed in an atomic manner -- this could be called from the interrupt context, after all. The problem is that, if the stream goes further and reaches to the CLOSE state immediately, the stream might be still being processed in snd_pcm_period_elapsed() in the interrupt context, and hits a NULL dereference. Such a crash happens because of the atomic operation, and we can't wait until the stream-stop finishes. For addressing such a problem, this commit adds a new PCM ops, sync_stop. This gets called at the appropriate places that need a sync with the stream-stop, i.e. at hw_params, prepare and hw_free. Some drivers already have a similar mechanism implemented locally, and we'll refactor the code later. Link: https://lore.kernel.org/r/20191117085308.23915-7-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de> |
||
|---|---|---|
| .. | ||
| ac97 | ||
| aoa | ||
| arm | ||
| atmel | ||
| core | ||
| drivers | ||
| firewire | ||
| hda | ||
| i2c | ||
| isa | ||
| mips | ||
| oss | ||
| parisc | ||
| pci | ||
| pcmcia | ||
| ppc | ||
| sh | ||
| soc | ||
| sparc | ||
| spi | ||
| synth | ||
| usb | ||
| x86 | ||
| xen | ||
| ac97_bus.c | ||
| Kconfig | ||
| last.c | ||
| Makefile | ||
| sound_core.c | ||