[issue1942] non-zero exclusive count(Re: locking against myself in getcacheblk()?)

[YONETANI Tomokazu]

On Tue, Dec 28, 2010 at 12:37:23AM +0000, Peter Avalos (via DragonFly issue tracker) wrote:
> 
> Peter Avalos <peter at theshell.com> added the comment:
> 
> I just got one of these non-zero exclusive count panics while doing a 'git 
> grep' in /usr/pkgsrc/.   Uptime for the machine was less than 2 days, so I'm 
> going to try to comment out TDF_DEADLKTREAT and see if I can duplicate it over 
> the next few days.  I'm uploading the vmcore to 
> http://www.theshell.com/~pavalos/crash1.tar.xz.

My vmcore.21 was also from the panic triggered by `git grep' and
that was why I tried `grep -r --mmap'.

However, even with buf01.patch applied and with the line setting
TDF_DEADLKTREAT removed, the following command can still panic
the system (you may have to run this command a few times, and/or
in a few different repositories depending on the size of the RAM
on the machine).  The patches are applied over 1a92ebbba.

$ cd /usr/src
$ PAGER='dd of=/dev/null bs=4m' git grep LK_

This PC is running a 32-bit kernel and it has 2G bytes of RAM.