Reproducable Infiniband panic

[Julian Stecklina]

On 06/07/2013 06:06 PM, John Baldwin wrote:
> On Friday, June 07, 2013 5:07:34 am Julian Stecklina wrote:
>> On 06/06/2013 08:57 PM, John Baldwin wrote:
>>> On Thursday, June 06, 2013 9:54:35 am Andriy Gapon wrote:
>> [...]
>>>> The problem seems to be in incorrect interaction between devfs_close_f 
> and
>>>> linux_file_dtor.  The latter expects curthread->td_fpop to have a valid 
> reasonable
>>>> value.  But the former sets curthread->td_fpop to fp only around 
> vnops.fo_close()
>>>> call and then restores it back to some (what?) previous value before 
> calling
>>>> devfs_fpdrop->devfs_destroy_cdevpriv.  In this case the previous value is 
> NULL.
>>>
>>> It is normally NULL in this case.  Why does linux_file_dtor even look at
>>> td_fpop?
>>>
>>> Ah.  I think it should not do that and make the data it uses in the dtor 
> more
>>> self-contained:
[...]

Seems to fix my panic. Thanks!

Julian