From: Donald Robson <Donald.Robson@imgtec.com>
To: "steven.price@arm.com" <steven.price@arm.com>,
"boris.brezillon@collabora.com" <boris.brezillon@collabora.com>
Cc: "neil.armstrong@linaro.org" <neil.armstrong@linaro.org>,
"drinkcat@chromium.org" <drinkcat@chromium.org>,
"kernel@collabora.com" <kernel@collabora.com>,
daniels <daniels@collabora.com>,
"Liviu.Dudau@arm.com" <Liviu.Dudau@arm.com>,
"dri-devel@lists.freedesktop.org"
<dri-devel@lists.freedesktop.org>,
Matt Coster <Matt.Coster@imgtec.com>,
"peron.clem@gmail.com" <peron.clem@gmail.com>,
"grant.likely@linaro.org" <grant.likely@linaro.org>,
"hanetzer@startmail.com" <hanetzer@startmail.com>,
"robin.murphy@arm.com" <robin.murphy@arm.com>,
"faith.ekstrand@collabora.com" <faith.ekstrand@collabora.com>
Subject: Re: [EXTERNAL] Re: [PATCH v3 03/14] drm/panthor: Add the device logical block
Date: Thu, 7 Dec 2023 11:11:15 +0000 [thread overview]
Message-ID: <c3816b4f74108ad7effbf0c9e92b440e34400b87.camel@imgtec.com> (raw)
In-Reply-To: <1b957ca4-71cf-42fd-ac81-1920592b952d@arm.com>
Thanks for the bug report!
Donald
On Thu, 2023-12-07 at 10:23 +0000, Steven Price wrote:
> *** CAUTION: This email originates from a source not known to Imagination Technologies. Think before you click a link or open an attachment ***
>
> On 07/12/2023 08:56, Boris Brezillon wrote:
> > On Thu, 7 Dec 2023 09:12:43 +0100
> > Boris Brezillon <boris.brezillon@collabora.com> wrote:
> >
> > > On Wed, 6 Dec 2023 16:55:42 +0000
> > > Steven Price <steven.price@arm.com> wrote:
> > >
> > > > On 04/12/2023 17:32, Boris Brezillon wrote:
> > > > > The panthor driver is designed in a modular way, where each logical
> > > > > block is dealing with a specific HW-block or software feature. In order
> > > > > for those blocks to communicate with each other, we need a central
> > > > > panthor_device collecting all the blocks, and exposing some common
> > > > > features, like interrupt handling, power management, reset, ...
> > > > >
> > > > > This what this panthor_device logical block is about.
> > > > >
> > > > > v3:
> > > > > - Add acks for the MIT+GPL2 relicensing
> > > > > - Fix 32-bit support
> > > > > - Shorten the sections protected by panthor_device::pm::mmio_lock to fix
> > > > > lock ordering issues.
> > > > > - Rename panthor_device::pm::lock into panthor_device::pm::mmio_lock to
> > > > > better reflect what this lock is protecting
> > > > > - Use dev_err_probe()
> > > > > - Make sure we call drm_dev_exit() when something fails half-way in
> > > > > panthor_device_reset_work()
> > > > > - Replace CSF_GPU_LATEST_FLUSH_ID_DEFAULT with a constant '1' and a
> > > > > comment to explain. Also remove setting the dummy flush ID on suspend.
> > > > > - Remove drm_WARN_ON() in panthor_exception_name()
> > > > > - Check pirq->suspended in panthor_xxx_irq_raw_handler()
> > > > >
> > > > > Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
> > > > > Signed-off-by: Steven Price <steven.price@arm.com>
> > > > > Acked-by: Steven Price <steven.price@arm.com> # MIT+GPL2 relicensing,Arm
> > > > > Acked-by: Grant Likely <grant.likely@linaro.org> # MIT+GPL2 relicensing,Linaro
> > > > > Acked-by: Boris Brezillon <boris.brezillon@collabora.com> # MIT+GPL2 relicensing,Collabora
> > > >
> > > > We still have the "FIXME: this is racy"
> > >
> > > Yeah, I still didn't find a proper solution for that.
> >
> > This [1] should fix the race condition in the unplug path.
> >
> > [1]https://urldefense.com/v3/__https://gitlab.freedesktop.org/panfrost/linux/-/commit/b79b28069e524ae7fea22a9a158b870eab2d5f9a__;!!KCwjcDI!1x9mqPx9K2SprWdgzBBRExLDu8uVajVeJcmlMkMufmIqJi5TYLqiDhhBr1hlnBQQUVgHnJKnWInjn7rWq0H_iLg$
>
> Looks like it should do the job. I'm surprised that we're the only ones
> to face this though.
>
> Looking at the new imagination driver it appears there's a similar problem:
>
> pvr_device_lost() uses a boolean 'lost' to track multiple calls but that
> boolean isn't protected by any specific lock (AFAICT). Indeed
> pvr_device_lost() calls drm_dev_unplug() while in a drm_dev_enter()
> critical section (see pvr_mmu_flush_exec()). If I'm not mistaken that's
> the same problem we discussed and isn't allowed? drm_dev_unplug() will
> synchronise on the SRCU that drm_dev_enter() is holding.
>
> +CC: Frank, Donald, Matt from Imagination.
>
> Steve
>
next prev parent reply other threads:[~2023-12-07 11:11 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-04 17:32 [PATCH v3 00/14] drm: Add a driver for CSF-based Mali GPUs Boris Brezillon
2023-12-04 17:32 ` [PATCH v3 01/14] drm/panthor: Add uAPI Boris Brezillon
2023-12-06 16:17 ` Steven Price
2023-12-18 13:20 ` Chris Diamand
2024-01-15 11:18 ` Boris Brezillon
2023-12-04 17:32 ` [PATCH v3 02/14] drm/panthor: Add GPU register definitions Boris Brezillon
2023-12-06 16:23 ` Steven Price
2023-12-04 17:32 ` [PATCH v3 03/14] drm/panthor: Add the device logical block Boris Brezillon
2023-12-06 16:55 ` Steven Price
2023-12-07 8:12 ` Boris Brezillon
2023-12-07 8:56 ` Boris Brezillon
2023-12-07 10:23 ` Steven Price
2023-12-07 10:49 ` Boris Brezillon
2023-12-07 11:11 ` Donald Robson [this message]
2023-12-22 13:26 ` Liviu Dudau
2023-12-22 14:04 ` Boris Brezillon
2023-12-04 17:32 ` [PATCH v3 04/14] drm/panthor: Add the GPU " Boris Brezillon
2023-12-07 16:05 ` Steven Price
2023-12-04 17:32 ` [PATCH v3 05/14] drm/panthor: Add GEM " Boris Brezillon
2023-12-07 16:38 ` Steven Price
2024-01-15 10:29 ` Boris Brezillon
2023-12-04 17:32 ` [PATCH v3 06/14] drm/panthor: Add the devfreq " Boris Brezillon
2023-12-05 9:42 ` Clément Péron
2023-12-04 17:33 ` [PATCH v3 07/14] drm/panthor: Add the MMU/VM " Boris Brezillon
2023-12-08 14:28 ` Steven Price
2024-01-15 11:04 ` Boris Brezillon
2024-01-15 17:31 ` Boris Brezillon
2024-01-15 17:38 ` Boris Brezillon
2024-01-15 17:41 ` Boris Brezillon
2024-01-15 18:09 ` Boris Brezillon
2023-12-04 17:33 ` [PATCH v3 08/14] drm/panthor: Add the FW " Boris Brezillon
2023-12-08 15:39 ` Steven Price
2023-12-18 21:25 ` Chris Diamand
2024-01-15 11:37 ` Boris Brezillon
2024-01-22 16:34 ` Boris Brezillon
2024-01-22 21:14 ` Chris Diamand
2023-12-20 15:12 ` Liviu Dudau
2024-01-15 12:56 ` Boris Brezillon
2023-12-04 17:33 ` [PATCH v3 09/14] drm/panthor: Add the heap " Boris Brezillon
2023-12-08 16:27 ` Steven Price
2024-01-15 11:15 ` Boris Brezillon
2023-12-04 17:33 ` [PATCH v3 10/14] drm/panthor: Add the scheduler " Boris Brezillon
2023-12-11 16:27 ` Steven Price
2024-01-15 13:03 ` Boris Brezillon
2023-12-19 11:50 ` Ketil Johnsen
2024-01-15 13:05 ` Boris Brezillon
2023-12-20 19:59 ` Ketil Johnsen
2024-01-15 13:11 ` Boris Brezillon
2023-12-04 17:33 ` [PATCH v3 11/14] drm/panthor: Add the driver frontend block Boris Brezillon
2023-12-13 11:47 ` Steven Price
2023-12-20 16:24 ` Liviu Dudau
2024-01-15 12:59 ` Boris Brezillon
2023-12-04 17:33 ` [PATCH v3 12/14] drm/panthor: Allow driver compilation Boris Brezillon
2023-12-13 13:18 ` Steven Price
2023-12-04 17:33 ` [PATCH v3 13/14] dt-bindings: gpu: mali-valhall-csf: Add support for Arm Mali CSF GPUs Boris Brezillon
2023-12-04 19:29 ` Rob Herring
2023-12-05 8:46 ` Boris Brezillon
2023-12-05 20:48 ` Rob Herring
2023-12-06 10:59 ` Liviu Dudau
2024-01-22 16:37 ` Boris Brezillon
2023-12-04 17:33 ` [PATCH v3 14/14] drm/panthor: Add an entry to MAINTAINERS Boris Brezillon
2023-12-13 13:51 ` Steven Price
2023-12-04 18:09 ` [PATCH v3 00/14] drm: Add a driver for CSF-based Mali GPUs Clément Péron
2023-12-05 8:04 ` Boris Brezillon
2023-12-05 8:48 ` Boris Brezillon
2023-12-06 15:47 ` Steven Price
2023-12-06 16:28 ` Boris Brezillon
2023-12-10 4:58 ` Tatsuyuki Ishi
2023-12-11 8:52 ` Boris Brezillon
2023-12-11 18:18 ` Faith Ekstrand
2024-01-15 14:18 ` Boris Brezillon
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