panic, seems related to r234386

[Sergey Kandaurov]

On 8 May 2012 05:14, Doug Barton <dougb at freebsd.org> wrote:
> On 05/07/2012 13:11, Mateusz Guzik wrote:
>> On Mon, May 07, 2012 at 12:28:41PM -0700, Doug Barton wrote:
>>> On 05/06/2012 15:19, Sergey Kandaurov wrote:
>>>> On 7 May 2012 01:54, Doug Barton <dougb at freebsd.org> wrote:
>>>>> I got this with today's current, previous (working) kernel is r232719.
>>>>>
>>>>> panic: _mtx_lock_sleep: recursed on non-recursive mutex struct mount mtx
>>>>> @ /frontier/svn/head/sys/kern/vfs_subr.c:4595
>>>
>>> ...
>>>
>>>> Please try this patch.
>
> Ok, so far so good. Again, thanks for the quick response. I'm
> stress-testing my ext2fs partitions a bit atm, and everything seems Ok.
> I'll let you know if I run into any problems.
>
> So my next question is, does removing those locks present any risks?
> Should they be replaced by different locks, or were they just safety
> belts to start with?

Unlike in the previously used macro MNT_VNODE_FOREACH_ABORT_ILOCKED(),
the currently used macro MNT_VNODE_FOREACH_ALL_ABORT() manages
mount mutexes itself so you don't need to mess with them. The locking is there,
it's just hidden behind macros.

>
> Finally, should my next step be to advance to the latest current + your
> patch and see how I go from there?

Yep, so that patches will be tested before they go to head.

-- 
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