drm/msm: don't tear down KMS twice when KMS init fails

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When priv->kms_init() (mdp4_kms_init() / mdp5_kms_init()) fails partway
through, both display drivers already tear their KMS state down via
mdp4_destroy() / mdp5_kms_destroy() before returning the error. The
common error path in msm_drm_init() then runs msm_drm_uninit() ->
msm_drm_kms_uninit(), which tries to destroy the very same KMS a second
time, which causes a use-after-free crash.

Bring MDP4/MDP5 in line with the DPU driver whose dpu_kms_init() doesn't
perform error cleanup on the failure. Let the common path own the
cleanup, instead of freeing the KMS from their error paths.

The crash trace for the reference:

  __lock_acquire from lock_acquire (kernel/locking/lockdep.c:5906 kernel/locking/lockdep.c:5863)
  lock_acquire from touch_wq_lockdep_map (kernel/workqueue.c:4094 (discriminator 1))
  touch_wq_lockdep_map from __flush_workqueue (kernel/workqueue.c:4136)
  __flush_workqueue from msm_drm_kms_uninit (drivers/gpu/drm/msm/msm_kms.c:243 (discriminator 33))
  msm_drm_kms_uninit from msm_drm_uninit (drivers/gpu/drm/msm/msm_drv.c:93)
  msm_drm_uninit from msm_drm_init (drivers/gpu/drm/msm/msm_drv.c:184)
  msm_drm_init from try_to_bring_up_aggregate_device (drivers/base/component.c:249 drivers/base/component.c:227)
  try_to_bring_up_aggregate_device from __component_add (drivers/base/component.c:269 drivers/base/component.c:748)
  __component_add from dsi_host_attach (drivers/gpu/drm/msm/dsi/dsi_host.c:1739)
  dsi_host_attach from mipi_dsi_attach (drivers/gpu/drm/drm_mipi_dsi.c:383)
  mipi_dsi_attach from sharp_nt_panel_probe (drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c:247)

Fixes: 506efcba31 ("drm/msm: carve out KMS code from msm_drv.c")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/742068/
Link: https://lore.kernel.org/r/20260723-msm-fix-crash-v1-1-78fb4721c2d9@oss.qualcomm.com

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This commit is contained in:

Dmitry Baryshkov 2026-07-23 12:52:12 +03:00

parent 8834f5494a

commit 93c125e4ea

2 changed files with 11 additions and 22 deletions

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22

drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c

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11

drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c

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