[PATCH] drm/ttm: avoid allocation memory while spinlock is held v2

[Jerome Glisse]

On Mon, Feb 4, 2013 at 2:21 PM, Daniel Vetter <daniel at ffwll.ch> wrote:
> On Mon, Feb 4, 2013 at 7:34 PM,  <j.glisse at gmail.com> wrote:
>> From: Jerome Glisse <jglisse at redhat.com>
>>
>> We need to take reference on the sync object while holding the
>> fence spinlock but at the same time we don't want to allocate
>> memory while holding the spinlock. This patch make sure we
>> enforce both of this constraint.
>>
>> v2: actually test build it
>>
>> Fix https://bugzilla.redhat.com/show_bug.cgi?id=906296
>>
>> Signed-off-by: Jerome Glisse <jglisse at redhat.com>
>
> Isn't that just another iteration of
> https://patchwork.kernel.org/patch/1972071/ which somehow never
> reached -fixes?
> -Daniel

Yes but my version doesn't drop the lock before taking the ref, iirc
there might be a race if droping the lock and then taking it again.
Another process might race to unref the sync obj but i haven't
tortured too much my brain on how likely if at all this is possible.

Cheers,
Jerome