USB locks up system -- WAS Re: shutdown or acpi problem

[Steve Kargl]

On Sun, Nov 16, 2014 at 08:33:15PM +0100, Hans Petter Selasky wrote:
> 
> thread apply all bt
> 
> That will give you the backtrace of all threads. Grep for usbconfig, and 
> figure out which line is causing the problem in the kernel. Then look at 
> the USB explore threads and see where they are stuck in the detach of umass!
> 

I haven't tried the kgdb approach, yet.  I can say that the
problem is coming from sg device.  If I have 'device sg' in
my config file, the problems occur.  Removing 'device sg'
gives a working kernel.

If I do not start hald in /etc/rc.conf, everything works as 
expected.  Now, if hald was started at boot and I then stop
hald with '/usr/local/etc/rc.d/hald stop' then the one hald
relate process is not stopped. I've wrapped lines to keep this
short.

% ps axl | grep hald
 UID  PID PPID CPU PRI NI   VSZ   RSS MWCHAN   STAT TT  TIME      COMMAND
  0  1058    1 195  20  0 13180  3512      -      I  -  0:00.05
      hald-probe-storage: /dev/sg1 (hald-probe-storage)

Using the procstat as suggested by Adrian, I have

% procstat -ka 
1058 100157 hald-probe-storage hald-probe-stora mi_switch sleepq_switch
     sleepq_catch_signals sleepq_wait_sig _sleep sgread giant_read
     devfs_read_f dofileread kern_readv sys_read syscall Xint0x80_syscall 

-- 
Steve