Re: WARNING ... drivers/gpu/drm/ttm/ttm_bo_vm.c...

[Thomas Hellstrom <thellstrom@vmware.com>]

Hi, David!

Thanks for the reply.

Actually I just got CC'd on the Fedora Bug. I haven't seen this either,
so I can't provide more info...

What I was thinking was that maybe after a fork, vma->vm_file->f_mapping
of the child process wasn't set to the same value as the
parent...

/Thomas



On 04/09/2014 08:54 PM, David Herrmann wrote:
> Hi Thomas
>
> On Tue, Apr 8, 2014 at 7:11 AM, Thomas Hellstrom <thellstrom@vmware.com> wrote:
>> Hi, David,
>>
>> Are there any dev_mapping changes in 3.15 that could cause this?
>> Do we know what happens to vma->vm_file->f_mapping during fork?
> Sorry, I was traveling. Yes, there have been changes, but I converted
> all drivers properly. We now set file->f_mapping in drm_fops.c to
> dev->anon_inode->i_mapping during open(). All the ttm stuff now sets
> ttm->dev_mapping to the same during ttm init so I have no idea why
> that assertion fails. The vmwgfx driver sets it correctly in
> vmw_driver_load() and I cannot find any code changing it.
>
> I also cannot reproduce it. Can you provide some more information?
> Like what is vma->vm_file set to? What is ttm->dev_mapping? What is
> drm_device->anon_inode->i_mapping? What is
> &drm_device->anon_inode->i_data? All these should _always_ be the
> same.
>
> Btw., grep'ping for '_mapping' usually shows all related code, which I
> reviewed and all looks good.
>
> Thanks
> David