Re: 2.6.36: Sound stop working

[Takashi Iwai <tiwai@suse.de>]

At Thu, 12 Aug 2010 23:24:43 +0200,
Jiri Slaby wrote:
> 
> On 08/12/2010 11:18 PM, Linus Torvalds wrote:
> > On Thu, Aug 12, 2010 at 2:01 PM, Jiri Slaby <jirislaby@gmail.com> wrote:
> >> Probably I got into this problem yesterday. Found out that PA fails to
> >> open /dev/snd/pcmC0D0p _second_ time. It opens it, then closes, then
> >> opens it again and gets EBUSY. aplay is OK.
> 
> Perfectly reproducible in qemu-kvm with ac97 soundhw, i.e. intel8x0
> driver. Just in case you want to debug that easily.

And the below is a minimal test case to simulate the situation
PulseAudio does.


Takashi

===

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/inotify.h>
#include <unistd.h>

int main()
{
	int fd;

	inotify_add_watch(inotify_init(), "/dev/snd", IN_CLOSE_WRITE);

	fd = open("/dev/snd/pcmC0D0p", O_RDWR | O_NONBLOCK);
	if (fd < 0)
		perror("open1");
	else
		close(fd);
	fd = open("/dev/snd/pcmC0D0p", O_RDWR | O_NONBLOCK);
	if (fd < 0)
		perror("open2");
	else
		close(fd);
	return 0;
}