Re: kern/50491: unkillable wait in usbd_transfer while using usmsc0 on raspberry pi 2

[Nick Hudson <nick.hudson%gmx.co.uk@localhost>]

On 12/3/2015 5:30 AM, Michael Plass wrote:
> The following reply was made to PR kern/50491; it has been noted by GNATS.
>
> From: Michael Plass <mfpnb%plass-family.net@localhost>
> To: gnats-bugs%NetBSD.org@localhost
> Cc: Michael Plass <mfpnb%plass-family.net@localhost>
> Subject: Re: kern/50491: unkillable wait in usbd_transfer while using usmsc0 on raspberry pi 2
> Date: Wed, 2 Dec 2015 21:26:11 -0800
>
>   Nick,
>   
>   I saw one of the 'usbd_do_request: not in process context' messages go by
>   (actually while still coming up to multiuser mode), but apparently DEBUG was
>   not defined, so the ASSERT_SLEEPABLE() was a NOP. I've rebuilt with a call to
>   assert_sleepable() instead, and I'll run with that.
Oops. Any reason to not define DEBUG? assert_sleepable should do, but 
they more checks the better.




>   PID    LID S CPU     FLAGS       STRUCT LWP *               NAME WAIT
>   230      1 3   0         0           bacfab60            cleanup tstile


>   2583     1 3   3         0           ba46a0c0               sshd tstile

>   0       31 3   3       200           bada4880          softclk/3 tstile


>   0        5 3   0       200           baf05340          softclk/0 tstile

>   0        3 3   0       200           baf058c0          softnet/0 tstile


Backtraces from these might help, but see below...

>   db{0}> bt/t 0t230
>   trace: pid 230 lid 1 at 0xbaccdd4c
>   0xbaccdd4c: netbsd:mi_switch+0x10
>   0xbaccdd7c: netbsd:sleepq_block+0xb4
>   0xbaccddbc: netbsd:turnstile_block+0x3e8
>   0xbaccde1c: netbsd:mutex_enter+0x220
>   0xbaccde3c: netbsd:sosetlock+0x58
>   0xbaccde6c: netbsd:tcp_attach_wrapper+0x30
>   0xbaccde9c: netbsd:socreate+0x158
>   0xbaccdee4: netbsd:fsocreate+0xac
>   0xbaccdf0c: netbsd:sys___socket30+0x30
>   0xbaccdf7c: netbsd:syscall+0x88
>   0xbaccdfac: netbsd:swi_handler+0x98

Blocked on softnet_lock in sosetlock

x/x softnet_lock should tell us who owns it. Get a backtrace from the 
offending lwp.

Nick