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* Fix MST VCPI lookup and modeset-lock splat
@ 2026-04-30  3:29 Suraj Kandpal
  2026-04-30  3:29 ` [PATCH 1/2] drm/915/hdcp: Use new MST topology state in intel_conn_to_vcpi() Suraj Kandpal
                   ` (4 more replies)
  0 siblings, 5 replies; 9+ messages in thread
From: Suraj Kandpal @ 2026-04-30  3:29 UTC (permalink / raw)
  To: intel-xe, intel-gfx
  Cc: ankit.k.nautiyal, fnu.vishwanatha, santhosh.reddy.guddati,
	Suraj Kandpal

intel_conn_to_vcpi() is called from the HDCP enable path in commit_tail
to look
up the VCPI of the MST stream that HDCP is being enabled on. Today it
reads the
topology state directly from mgr->base.state and takes mgr->base.lock
with the
in-flight state->base.acquire_ctx.

This breaks in two ways on MST + HDCP, especially when an
ALLOCATE_PAYLOAD
transaction is being driven on the mgr just before HDCP enable runs:

- mgr->base.state's payload list is being mutated in place by the MST
  payload code, so drm_atomic_get_mst_payload_state() can fail to find
  the entry for this connector's port. That trips drm_WARN_ON(!payload)
  and HDCP ends up programmed with VCPI 0.

- By the time we reach commit_tail/encoder enable,
  state->base.acquire_ctx
  is no longer valid for acquiring new modeset locks. Taking
  mgr->base.lock here produces a modeset-lock splat.

This series fixes both.

Suraj Kandpal (2):
  drm/915/hdcp: Use new MST topology state in intel_conn_to_vcpi()
  drm/i915/hdcp: Drop mgr->base.lock acquisition in intel_conn_to_vcpi()

 drivers/gpu/drm/i915/display/intel_hdcp.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

-- 
2.34.1


^ permalink raw reply	[flat|nested] 9+ messages in thread
* [PATCH 0/2] Fix MST VCPI lookup and modeset-lock splat
@ 2026-04-30  3:32 Suraj Kandpal
  2026-04-30  3:32 ` [PATCH 2/2] drm/i915/hdcp: Drop mgr->base.lock acquisition in intel_conn_to_vcpi() Suraj Kandpal
  0 siblings, 1 reply; 9+ messages in thread
From: Suraj Kandpal @ 2026-04-30  3:32 UTC (permalink / raw)
  To: intel-xe, intel-gfx
  Cc: ankit.k.nautiyal, fnu.vishwanatha, santhosh.reddy.guddati,
	Suraj Kandpal

intel_conn_to_vcpi() is called from the HDCP enable path in commit_tail
to look
up the VCPI of the MST stream that HDCP is being enabled on. Today it
reads the
topology state directly from mgr->base.state and takes mgr->base.lock
with the
in-flight state->base.acquire_ctx.

This breaks in two ways on MST + HDCP, especially when an
ALLOCATE_PAYLOAD
transaction is being driven on the mgr just before HDCP enable runs:

- mgr->base.state's payload list is being mutated in place by the MST
  payload code, so drm_atomic_get_mst_payload_state() can fail to find
  the entry for this connector's port. That trips drm_WARN_ON(!payload)
  and HDCP ends up programmed with VCPI 0.

- By the time we reach commit_tail/encoder enable,
  state->base.acquire_ctx
  is no longer valid for acquiring new modeset locks. Taking
  mgr->base.lock here produces a modeset-lock splat.

This series fixes both.

Suraj Kandpal (2):
  drm/915/hdcp: Use new MST topology state in intel_conn_to_vcpi()
  drm/i915/hdcp: Drop mgr->base.lock acquisition in intel_conn_to_vcpi()

 drivers/gpu/drm/i915/display/intel_hdcp.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

-- 
2.34.1


^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2026-05-04  9:53 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-04-30  3:29 Fix MST VCPI lookup and modeset-lock splat Suraj Kandpal
2026-04-30  3:29 ` [PATCH 1/2] drm/915/hdcp: Use new MST topology state in intel_conn_to_vcpi() Suraj Kandpal
2026-05-04  6:20   ` Reddy Guddati, Santhosh
2026-04-30  3:29 ` [PATCH 2/2] drm/i915/hdcp: Drop mgr->base.lock acquisition " Suraj Kandpal
2026-05-04  9:53   ` Reddy Guddati, Santhosh
2026-04-30  3:36 ` ✓ CI.KUnit: success for series starting with [1/2] drm/915/hdcp: Use new MST topology state " Patchwork
2026-04-30  4:25 ` ✓ Xe.CI.BAT: " Patchwork
2026-04-30 14:44 ` ✗ Xe.CI.FULL: failure " Patchwork
  -- strict thread matches above, loose matches on Subject: below --
2026-04-30  3:32 [PATCH 0/2] Fix MST VCPI lookup and modeset-lock splat Suraj Kandpal
2026-04-30  3:32 ` [PATCH 2/2] drm/i915/hdcp: Drop mgr->base.lock acquisition in intel_conn_to_vcpi() Suraj Kandpal

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