Re: autofs4 hang in 2.6.37-rc1

[Avi Kivity <avi@redhat.com>]

On 11/14/2010 05:15 PM, Arnd Bergmann wrote:
> On Sunday 14 November 2010 14:51:04 Avi Kivity wrote:
> >  automount     S ffff88012a28a680     0   399      1 0x00000000
> >    ffff88012a07bd08 0000000000000082 0000000000000000 0000000000000000
> >    ffff88012a07a010 ffff88012a07bfd8 0000000000011800 ffff88012693c260
> >    ffff88012693c5d0 ffff88012693c5c8 0000000000011800 0000000000011800
> >  Call Trace:
> >    [<ffffffff81056197>] ? prepare_to_wait+0x67/0x74
> >    [<ffffffff811b23eb>] autofs4_wait+0x5a4/0x6d5
> >    [<ffffffff81055f25>] ? autoremove_wake_function+0x0/0x34
> >    [<ffffffff811b2ba5>] autofs4_do_expire_multi+0x5b/0xa3
> >    [<ffffffff811b2c39>] autofs4_expire_multi+0x4c/0x54
> >    [<ffffffff811b1750>] autofs4_root_ioctl_unlocked+0x23e/0x252
> >    [<ffffffff811b1808>] autofs4_root_ioctl+0x39/0x53
> >    [<ffffffff810f5e5c>] do_vfs_ioctl+0x557/0x5bb
> >    [<ffffffff810ca644>] ? remove_vma+0x6e/0x76
> >    [<ffffffff810cb6a2>] ? do_munmap+0x31c/0x33e
> >    [<ffffffff810f5f02>] sys_ioctl+0x42/0x65
> >    [<ffffffff81002b42>] system_call_fastpath+0x16/0x1b
> >
> >
> >  Shouldn't we drop autofs4_ioctl_mutex while we wait?
>
> If the ioctl can sleep for multiple seconds, the mutex should
> indeed be dropped, and that would be safe because we used to
> do the same with the BKL.
>
> The question is why this would sleep for more than 120 seconds.
>

Let's fix first and ask questions later.

-- 
error compiling committee.c: too many arguments to function