Commit cd95ef00 authored by Wayne Lin's avatar Wayne Lin Committed by Alex Deucher
Browse files

drm/amd/display: Fix secure display lock problems 



[Why]
Find out few locks problems while doing secure display. They are
following few parts:

1. crc_rd_work_lock in amdgpu_dm_crtc_handle_crc_window_irq() should
also use spin_lock_irqsave instead of spin_lock_irq.

2. In crc_win_update_set(), crc_rd_work_lock should be grabbed after
obtaining lock event_lock. Otherwise, will cause deadlock by conflicting
the lock order in amdgpu_dm_crtc_handle_crc_window_irq()

3. flush_work() in crc_win_update_set() is no need and will cause
deadlock since amdgpu_dm_crtc_notify_ta_to_read() also tries to grab
lock crc_rd_work_lock.

[How]
Fix above problems.

Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarWayne Lin <Wayne.Lin@amd.com>
Reviewed-by: default avatarSolomon Chiu <Solomon.Chiu@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 4870bd88

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c

+5 −5
Original line number Diff line number Diff line
@@ -433,7 +433,7 @@ void amdgpu_dm_crtc_handle_crc_window_irq(struct drm_crtc *crtc) 
	struct amdgpu_device *adev = NULL;

	struct crc_rd_work *crc_rd_wrk = NULL;

	struct crc_params *crc_window = NULL, tmp_window;

	unsigned long flags;

	unsigned long flags1, flags2;

	struct crtc_position position;

	uint32_t v_blank;

	uint32_t v_back_porch;
@@ -447,7 +447,7 @@ void amdgpu_dm_crtc_handle_crc_window_irq(struct drm_crtc *crtc) 
	adev = drm_to_adev(crtc->dev);

	drm_dev = crtc->dev;



	spin_lock_irqsave(&drm_dev->event_lock, flags);

	spin_lock_irqsave(&drm_dev->event_lock, flags1);

	stream_state = acrtc->dm_irq_params.stream;

	cur_crc_src = acrtc->dm_irq_params.crc_src;

	timing_out = &stream_state->timing;
@@ -508,10 +508,10 @@ void amdgpu_dm_crtc_handle_crc_window_irq(struct drm_crtc *crtc) 
				if (acrtc->dm_irq_params.crc_window.skip_frame_cnt == 0) {

					if (adev->dm.crc_rd_wrk) {

						crc_rd_wrk = adev->dm.crc_rd_wrk;

						spin_lock_irq(&crc_rd_wrk->crc_rd_work_lock);

						spin_lock_irqsave(&crc_rd_wrk->crc_rd_work_lock, flags2);

						crc_rd_wrk->phy_inst =

							stream_state->link->link_enc_hw_inst;

						spin_unlock_irq(&crc_rd_wrk->crc_rd_work_lock);

						spin_unlock_irqrestore(&crc_rd_wrk->crc_rd_work_lock, flags2);

						schedule_work(&crc_rd_wrk->notify_ta_work);

					}

				} else {
@@ -522,7 +522,7 @@ void amdgpu_dm_crtc_handle_crc_window_irq(struct drm_crtc *crtc) 
	}



cleanup:

	spin_unlock_irqrestore(&drm_dev->event_lock, flags);

	spin_unlock_irqrestore(&drm_dev->event_lock, flags1);

}



void amdgpu_dm_crtc_secure_display_resume(struct amdgpu_device *adev)

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c

+2 −4
Original line number Diff line number Diff line
@@ -2695,14 +2695,12 @@ static int crc_win_update_set(void *data, u64 val) 
	struct crc_rd_work *crc_rd_wrk = adev->dm.crc_rd_wrk;



	if (val) {

		spin_lock_irq(&crc_rd_wrk->crc_rd_work_lock);

		spin_lock_irq(&adev_to_drm(adev)->event_lock);

		spin_lock_irq(&crc_rd_wrk->crc_rd_work_lock);

		if (crc_rd_wrk && crc_rd_wrk->crtc) {

			old_crtc = crc_rd_wrk->crtc;

			old_acrtc = to_amdgpu_crtc(old_crtc);

			flush_work(&adev->dm.crc_rd_wrk->notify_ta_work);

		}



		new_acrtc = to_amdgpu_crtc(new_crtc);



		if (old_crtc && old_crtc != new_crtc) {
@@ -2720,8 +2718,8 @@ static int crc_win_update_set(void *data, u64 val) 
			new_acrtc->dm_irq_params.crc_window.skip_frame_cnt = 0;

			crc_rd_wrk->crtc = new_crtc;

		}

		spin_unlock_irq(&adev_to_drm(adev)->event_lock);

		spin_unlock_irq(&crc_rd_wrk->crc_rd_work_lock);

		spin_unlock_irq(&adev_to_drm(adev)->event_lock);

	}



	return 0;