Intel-GFX Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Suraj Kandpal <suraj.kandpal@intel.com>
To: intel-xe@lists.freedesktop.org, intel-gfx@lists.freedesktop.org
Cc: ankit.k.nautiyal@intel.com, fnu.vishwanatha@intel.com,
	santhosh.reddy.guddati@intel.com,
	Suraj Kandpal <suraj.kandpal@intel.com>
Subject: [PATCH 2/2] drm/i915/hdcp: Drop mgr->base.lock acquisition in intel_conn_to_vcpi()
Date: Thu, 30 Apr 2026 09:02:22 +0530	[thread overview]
Message-ID: <20260430033222.3411174-3-suraj.kandpal@intel.com> (raw)
In-Reply-To: <20260430033222.3411174-1-suraj.kandpal@intel.com>

Now that intel_conn_to_vcpi() reads the MST topology state via
drm_atomic_get_new_mst_topology_state(), the topology state belongs
to this atomic commit and is already serialized through the atomic
state's private object machinery. There is no need to additionally
take mgr->base.lock here.
Taking it from the HDCP enable path in commit_tail with
state->base.acquire_ctx is also unsafe: by this point the
acquire_ctx is no longer in a state where new modeset locks may be
acquired through it, which produces a modeset-lock splat on MST +
HDCP. Drop the drm_modeset_lock() call.

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
---
 drivers/gpu/drm/i915/display/intel_hdcp.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index 91d2d7d823cc..a5d4e77f810f 100644
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -80,9 +80,8 @@ static int intel_conn_to_vcpi(struct intel_atomic_state *state,
 	/* For HDMI this is forced to be 0x0. For DP SST also this is 0x0. */
 	if (!connector->mst.port)
 		return 0;
-	mgr = connector->mst.port->mgr;
 
-	drm_modeset_lock(&mgr->base.lock, state->base.acquire_ctx);
+	mgr = connector->mst.port->mgr;
 	mst_state = drm_atomic_get_new_mst_topology_state(&state->base, mgr);
 	if (!mst_state) {
 		drm_dbg_kms(display->drm, "MST topology still not created\n");
-- 
2.34.1


  parent reply	other threads:[~2026-04-30  3:32 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-30  3:32 [PATCH 0/2] Fix MST VCPI lookup and modeset-lock splat Suraj Kandpal
2026-04-30  3:32 ` [PATCH 1/2] drm/915/hdcp: Use new MST topology state in intel_conn_to_vcpi() Suraj Kandpal
2026-04-30  3:32 ` Suraj Kandpal [this message]
2026-04-30  4:56 ` ✓ i915.CI.BAT: success for Fix MST VCPI lookup and modeset-lock splat Patchwork
2026-04-30 10:50 ` ✗ i915.CI.Full: failure " Patchwork
  -- strict thread matches above, loose matches on Subject: below --
2026-04-30  3:29 Suraj Kandpal
2026-04-30  3:29 ` [PATCH 2/2] drm/i915/hdcp: Drop mgr->base.lock acquisition in intel_conn_to_vcpi() Suraj Kandpal
2026-05-04  9:53   ` Reddy Guddati, Santhosh

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260430033222.3411174-3-suraj.kandpal@intel.com \
    --to=suraj.kandpal@intel.com \
    --cc=ankit.k.nautiyal@intel.com \
    --cc=fnu.vishwanatha@intel.com \
    --cc=intel-gfx@lists.freedesktop.org \
    --cc=intel-xe@lists.freedesktop.org \
    --cc=santhosh.reddy.guddati@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox