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  1. 16 2月, 2023 1 次提交
  3. 09 2月, 2023 8 次提交
  5. 02 2月, 2023 1 次提交
  7. 27 1月, 2023 1 次提交
  9. 26 1月, 2023 3 次提交
  11. 19 1月, 2023 5 次提交
  13. 05 1月, 2023 1 次提交
  15. 23 12月, 2022 1 次提交
  17. 14 12月, 2022 1 次提交
  19. 02 12月, 2022 2 次提交
  21. 30 11月, 2022 2 次提交
  23. 23 11月, 2022 3 次提交
  25. 22 11月, 2022 4 次提交
  27. 17 11月, 2022 3 次提交
    • L
      drm/amdgpu/dm/dp_mst: Don't grab mst_mgr->lock when computing DSC state · 14b651b2
      由 Lyude Paul 提交于 
      Now that we've fixed the issue with using the incorrect topology manager,
we're actually grabbing the topology manager's lock - and consequently
deadlocking. Luckily for us though, there's actually nothing in AMD's DSC
state computation code that really should need this lock. The one exception
is the mutex_lock() in dm_dp_mst_is_port_support_mode(), however we grab no
locks beneath &mgr->lock there so that should be fine to leave be.

Gitlab issue: https://gitlab.freedesktop.org/drm/amd/-/issues/2171Signed-off-by: NLyude Paul <lyude@redhat.com>
Fixes: 8c20a1ed ("drm/amd/display: MST DSC compute fair share")
Cc: <stable@vger.kernel.org> # v5.6+
Reviewed-by: NWayne Lin <Wayne.Lin@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
      14b651b2
    • L
      drm/amdgpu/dm/mst: Use the correct topology mgr pointer in amdgpu_dm_connector · d3e2c664
      由 Lyude Paul 提交于 
      This bug hurt me. Basically, it appears that we've been grabbing the
entirely wrong mutex in the MST DSC computation code for amdgpu! While
we've been grabbing:

  amdgpu_dm_connector->mst_mgr

That's zero-initialized memory, because the only connectors we'll ever
actually be doing DSC computations for are MST ports. Which have mst_mgr
zero-initialized, and instead have the correct topology mgr pointer located
at:

  amdgpu_dm_connector->mst_port->mgr;

I'm a bit impressed that until now, this code has managed not to crash
anyone's systems! It does seem to cause a warning in LOCKDEP though:

  [   66.637670] DEBUG_LOCKS_WARN_ON(lock->magic != lock)

This was causing the problems that appeared to have been introduced by:

  commit 4d07b0bc ("drm/display/dp_mst: Move all payload info into the atomic state")

This wasn't actually where they came from though. Presumably, before the
only thing we were doing with the topology mgr pointer was attempting to
grab mst_mgr->lock. Since the above commit however, we grab much more
information from mst_mgr including the atomic MST state and respective
modesetting locks.

This patch also implies that up until now, it's quite likely we could be
susceptible to race conditions when going through the MST topology state
for DSC computations since we technically will not have grabbed any lock
when going through it.

So, let's fix this by adjusting all the respective code paths to look at
the right pointer and skip things that aren't actual MST connectors from a
topology.

Gitlab issue: https://gitlab.freedesktop.org/drm/amd/-/issues/2171Signed-off-by: NLyude Paul <lyude@redhat.com>
Fixes: 8c20a1ed ("drm/amd/display: MST DSC compute fair share")
Cc: <stable@vger.kernel.org> # v5.6+
Reviewed-by: NWayne Lin <Wayne.Lin@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
      d3e2c664
    • L
      drm/amdgpu/mst: Stop ignoring error codes and deadlocking · 7cce4cd6
      由 Lyude Paul 提交于 
      It appears that amdgpu makes the mistake of completely ignoring the return
values from the DP MST helpers, and instead just returns a simple
true/false. In this case, it seems to have come back to bite us because as
a result of simply returning false from
compute_mst_dsc_configs_for_state(), amdgpu had no way of telling when a
deadlock happened from these helpers. This could definitely result in some
kernel splats.

V2:
* Address Wayne's comments (fix another bunch of spots where we weren't
  passing down return codes)
Signed-off-by: NLyude Paul <lyude@redhat.com>
Fixes: 8c20a1ed ("drm/amd/display: MST DSC compute fair share")
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: <stable@vger.kernel.org> # v5.6+
Reviewed-by: NWayne Lin <Wayne.Lin@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
      7cce4cd6
  29. 16 11月, 2022 4 次提交