Hello Daniel,
On 2/24/22 13:59, Daniel Vetter wrote:
Some things changed, and add two useful links.
Cc: Javier Martinez Canillas javierm@redhat.com Cc: Pekka Paalanen ppaalanen@gmail.com Cc: gpiccoli@igalia.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com
Documentation/gpu/todo.rst | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-)
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index 7bf7f2111696..283d35a500bd 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -475,8 +475,12 @@ This is a really varied tasks with lots of little bits and pieces: achieved by using an IPI to the local processor.
- There's a massive confusion of different panic handlers. DRM fbdev emulation
- helpers have one, but on top of that the fbcon code itself also has one. We
- need to make sure that they stop fighting over each another.
- helpers had their own (long removed), but on top of that the fbcon code itself
- also has one. We need to make sure that they stop fighting over each another.
The "over each another" sounds a little bit off, shouldn't be "over each other" ?
- This is worked around by checking ``oops_in_progress`` at various entry points
- into the DRM fbdev emulation helpers. A much cleaner approach here would be to
- switch fbcon to the `threaded printk support
- https://lwn.net/Articles/800946/`_.
- ``drm_can_sleep()`` is a mess. It hides real bugs in normal operations and isn't a full solution for panic paths. We need to make sure that it only
@@ -488,16 +492,9 @@ This is a really varied tasks with lots of little bits and pieces: even spinlocks (because NMI and hardirq can panic too). We need to either make sure to not call such paths, or trylock everything. Really tricky.
-* For the above locking troubles reasons it's pretty much impossible to
- attempt a synchronous modeset from panic handlers. The only thing we could
- try to achive is an atomic ``set_base`` of the primary plane, and hope that
- it shows up. Everything else probably needs to be delayed to some worker or
- something else which happens later on. Otherwise it just kills the box
- harder, prevent the panic from going out on e.g. netconsole.
-* There's also proposal for a simplied DRM console instead of the full-blown
- fbcon and DRM fbdev emulation. Any kind of panic handling tricks should
- obviously work for both console, in case we ever get kmslog merged.
+* A clean solution would be an entirely separate panic output support in KMS,
- bypassing the current fbcon support. See `[PATCH v2 0/3] drm: Add panic handling
- https://lore.kernel.org/dri-devel/20190311174218.51899-1-noralf@tronnes.org/`_.
Having these two links in the docs is very useful. Thanks a lot for adding that.
Reviewed-by: Javier Martinez Canillas javierm@redhat.com
Best regards,