6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Luigi Lauro [ Upstream commit b456f591f925fbd6b33770d0eec1b51c2f9d41c1 ] amdgpu_dm_commit_streams() takes a runtime PM reference for every active CRTC that needs a modeset and has a new stream, but amdgpu_dm_atomic_commit_tail() drops one only for each CRTC that goes from active to inactive. A modeset of a CRTC that is already active (a mode change, or anything else that needs a full modeset) therefore leaks one reference. Once that has happened, the usage count no longer returns to zero with every CRTC off, and the device cannot runtime suspend again until reboot. The two also disagree the other way when a CRTC turns on without a stream ("Failed to create new stream"): no reference is taken, but one is dropped when it turns off. Take the reference in the loop that counts the disabled CRTCs, on the mirror condition: when the CRTC goes from inactive to active, which is what the commit that added it intended ("every time we enable a previously disabled CRTC"). Each active CRTC then holds exactly one reference. Tested on an RX 9070 XT (Navi 48) over OCuLink, with the change backported to 7.2.9: an unplugged connector forced on, then mode A on a CRTC, mode B on the same active CRTC, and the CRTC off, three rounds in a row. The usage count rose by 3 with the stock module, by 0 with this patch, and by 3 again after reloading the stock module. Fixes: 97028037a38a ("drm/amdgpu: Grab/put runtime PM references in atomic_commit_tail()") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/5951 Assisted-by: Claude:claude-opus-5-5 Reviewed-by: Alex Deucher Signed-off-by: Luigi Lauro Signed-off-by: Alex Deucher (cherry picked from commit 59ef9a435499777b8e1c4e0eff52f813c64fb920) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index bb1fae39cd395..a77b55ff9321f 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -10550,8 +10550,6 @@ static void amdgpu_dm_commit_streams(struct drm_atomic_state *state, if (dm_old_crtc_state->stream) remove_stream(adev, acrtc, dm_old_crtc_state->stream); - pm_runtime_get_noresume(dev->dev); - acrtc->enabled = true; acrtc->hw_mode = new_crtc_state->mode; crtc->hwmode = new_crtc_state->mode; @@ -11024,8 +11022,13 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state) #ifdef CONFIG_DEBUG_FS enum amdgpu_dm_pipe_crc_source cur_crc_src; #endif - /* Count number of newly disabled CRTCs for dropping PM refs later. */ - if (old_crtc_state->active && !new_crtc_state->active) + /* + * One runtime PM reference per active CRTC: take it when the + * CRTC turns on, count it when it turns off for dropping later. + */ + if (!old_crtc_state->active && new_crtc_state->active) + pm_runtime_get_noresume(dev->dev); + else if (old_crtc_state->active && !new_crtc_state->active) crtc_disable_count++; dm_new_crtc_state = to_dm_crtc_state(new_crtc_state); -- 2.53.0