lkml.org 
[lkml]   [2018]   [Apr]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: INFO: rcu detected stall in io_playback_transfer
From
Date
Dmitry Vyukov wrote:
> Takashi has already fixed this. See this thread:
> https://groups.google.com/forum/#!searchin/syzkaller-bugs/%22INFO$3A$20rcu$20detected$20stall$20in$20snd_pcm_oss_write3$20(2)%22%7Csort:date/syzkaller-bugs/D2xWV7WTRDk/sCw_gImmCAAJ

Yes, I noticed it just before I post this. But the reason I posted this anyway
is that I feel that there is some other bug revealed by this reproducer.
How can Takashi' patch explain my observation (with linux-next-20180406) ?

/* Hits the stall */
int main(int argc, char *argv[])
{
const int fd = open("/dev/dsp1", O_RDWR);
int frag = (0 << 16) | 0;
char buf[48] = { };
unshare(CLONE_NEWNS);
ioctl(fd, SNDCTL_DSP_SETFRAGMENT, &frag);
write(fd, buf, sizeof(buf));
return 0;
}

/* Does not hit the stall */
int main(int argc, char *argv[])
{
const int fd = open("/dev/dsp1", O_RDWR);
int frag = (0 << 16) | 0;
char buf[48] = { };
ioctl(fd, SNDCTL_DSP_SETFRAGMENT, &frag);
write(fd, buf, sizeof(buf));
return 0;
}

/* Does not hit the stall */
int main(int argc, char *argv[])
{
const int fd = open("/dev/dsp1", O_RDWR);
int frag = (0 << 16) | 0;
char buf[48] = { };
unshare(CLONE_NEWNS);
ioctl(fd, SNDCTL_DSP_SETFRAGMENT, &frag);
write(fd, buf, sizeof(buf));
close(fd);
return 0;
}

\
 
 \ /
  Last update: 2018-04-08 15:29    [W:0.037 / U:0.104 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site