Re: [PATCH v4 5/6] dma-buf: Change locking policy for mmap()

From: Dmitry Osipenko
Date: Wed Jun 21 2023 - 14:18:14 EST


On 6/21/23 08:42, Christian König wrote:
> Am 20.06.23 um 17:58 schrieb Dmitry Osipenko:
>> On 5/31/23 22:58, Dmitry Osipenko wrote:
>>> On 5/30/23 01:39, Dmitry Osipenko wrote:
>>>> Change locking policy of mmap() callback, making exporters responsible
>>>> for handling dma-buf reservation locking. Previous locking policy
>>>> stated
>>>> that dma-buf is locked for both importers and exporters by the dma-buf
>>>> core, which caused a deadlock problem for DRM drivers in a case of
>>>> self-imported dma-bufs which required to take the lock from the DRM
>>>> exporter side.
>>>>
>>>> Reviewed-by: Emil Velikov <emil.l.velikov@xxxxxxxxx>
>>>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
>>>> ---
>>>>   drivers/dma-buf/dma-buf.c | 17 +++--------------
>>>>   1 file changed, 3 insertions(+), 14 deletions(-)
>>> Christian, you acked the drm patch of this series sometime ago, perhaps
>>> it also implies implicit ack to this patch, but I'd prefer to have the
>>> explicit ack. I'll apply this series to drm-misc later this week if
>>> you'll approve this dma-buf change. Thanks in advance!
>> I'll merge the patches tomorrow. If there are any additional comments,
>> then please don't hesitate to post them.
>
> Sorry for not responding earlier, I have been moving both my office as
> well as my household and still catching up.
>
> I don't have time for an in-deep review, but my ack stands for the whole
> series.

Thanks! I'll add yours ack and merge patches soon

--
Best regards,
Dmitry