kernel/linux.git/drivers/gpu/drm/amd/display/amdgpu_dm, branch v6.18.48

drm/amd/display: Fix NULL pointer dereference in amdgpu_dm_crtc_set_vblank()

2026-08-23T12:27:00+00:00

commit f2a1c4c6fe0a6fcde02e59dde546dba28d283635 upstream. amdgpu_dm_crtc_set_vblank() dereferences acrtc_state->stream when vblank is enabled/queried from DRM_IOCTL_MODE_CRTC_GET_SEQUENCE before a stream is attached to it. BUG: kernel NULL pointer dereference, address: 0000000000000008 RIP: amdgpu_dm_crtc_set_vblank+0x6b/0x4d0 [amdgpu] Call Trace: drm_vblank_enable drm_vblank_get drm_crtc_get_sequence_ioctl drm_ioctl_kernel drm_ioctl Reproduced by running VKCTS with WSI tests enabled on RADV. Guard the enable path on acrtc_state->stream being non-NULL, matching the existing checks in this function. Fixes: 34d66bc7ff10 ("drm/amd/display: Fix Xorg desktop unresponsive on Replay panel") Reviewed-by: Melissa Wen Signed-off-by: Samuel Pitoiset Signed-off-by: Alex Deucher (cherry picked from commit 7b1b31bf6942e6f43509b48da23f8e27269aac39) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

Revert "drm/amd/display: Fix backlight max_brightness to match exported range"

2026-08-19T16:18:06+00:00

This reverts commit 490ceacd2162de919a142bcb4eff363bb493b1de. This patch is apparently missing a dependency from 7.2 as users have not reported any regressions with 7.2-rc, but there are regressions on 6.18. The regression manifests as inconsistent lower brightness at the top end (e.g., around 98%). Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/5562 Signed-off-by: Alex Deucher Cc: Thorsten Leemhuis Cc: Sergio Callegari Cc: Mario Limonciello Signed-off-by: Sasha Levin

drm/amd/display: Exit idle optimizations before programming

2026-08-09T18:25:28+00:00

[ Upstream commit 8419331e64d92a8de5fc4feef0e305f201fb8b33 ] [Why] We need to exit PSR/IPS before programming. Before calling DC for programming in amdgpu_dm_commit_planes(), there's a vblank_control_workqueue flush. This waits for IPS and PSR exit. (See drm_vblank_on/off() > amdgpu_dm_crtc_set_vblank() --queue_work()-> amdgpu_dm_crtc_vblank_control_worker()) Prior to the tagged "Fixes:" change, drm_vblank_get() was called before the workqueue flush. This ordering ensures that PSR exit occurred before programming. After the "Fixes:" change, drm_vblank_get() is called after the workqueue flush, leading to programming while idle optimizations are still active. This can lead to incorrect flip_pending detection used by vblank event delivery. [How] Split the vblank_get() component of `dm_arm_vblank_event()` into `dm_arm_vblank_event_pre_programming()`, which is called before programming. Call it before the vblank_control_workqueue flush. Includes a drive-by cleanup of prepare_flip_isr(): the only caller is dm_arm_vblank_event() and it's simple enough to roll-in. v2: Fix checkpatch formatting warning on drm_arm_vblank_event_pre_programming() arg alignment. Fixes: 48ab86360af1 ("drm/amd/display: check GRPH_FLIP status before sending event") Cc: stable@vger.kernel.org Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/4141#note_3583205 Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/5527 Assisted-by: Codex:gpt-5.6-sol Assisted-by: Claude:opus-5 Suggested-by: David Weber Signed-off-by: Leo Li Reviewed-by: Mario Limonciello (AMD) Signed-off-by: Alex Deucher (cherry picked from commit 05984e29520a28c27f5a2388742c957a6a87ee7a) (cherry picked from commit 8419331e64d92a8de5fc4feef0e305f201fb8b33) Signed-off-by: Sasha Levin

drm/amd/display: check GRPH_FLIP status before sending event

2026-08-09T18:25:28+00:00

[ Upstream commit 48ab86360af117123eb1b15e38f068acf3826400 ] [Why] After unifying DCN interrupt sources under VUPDATE_NO_LOCK, we have two remaining issues to clean up: 1. On DCN, flip completion is now delivered from VUPDATE_NO_LOCK (dm_crtc_high_irq_handler) instead of GRPH_PFLIP. But VUPDATE_NO_LOCK fires every frame, regardless of whether a flip has latched. 2. There is a window during commit where a flip is armed (pflip_status = SUBMITTED) but not yet programmed into HW. If the VUPDATE_NO_LOCK fires in that window, its handler would deliver a flip event to userspace before HW has latched to it. If userspace then renders to what it believes is now the back buffer (but HW is still latched to it!), it will cause display corruption. This issue seemed to have been introduced by: commit 1159898a88db ("drm/amd/display: Handle commit plane with no FB.") Enabling replay or psr extended the duration of this window, and hence made corruption more likely to be observed. [How] * Move acrtc->event/pflip_status arming to after update_planes_and_stream_adapter() has programmed the flip into HW. This closes the window where pflip_status is SUBMITTED but the flip is not yet programmed. * Add dc_get_flip_pending_on_otg(), which reads the HUBP flip-pending status straight from HW for the pipe(s) bound to an OTG instance. It is keyed only by otg_inst and does not take or mutate a dc_plane_state, so it is safe to call from the OTG interrupt handler without racing a concurrent commit that may be modifying plane state. * Optimistically query for flip-pending after programming, in the event that HW latched to the new fb between programming start and arming event. If it latched, send the vblank event immediately, rather than wait for the next vblank IRQ. * In the VUPDATE_NO_LOCK handler, only deliver flip completion once dc_get_flip_pending_on_otg() reports the flip is no longer pending. Otherwise leave the flip armed and retry on the next vupdate. * For DCE, maintain the existing behavior of arming flips before programming, and relying on GRPH_FLIP to fire at HW latch. v2: * Drop flip_programmed completion object, instead move event/pflip_status arming after programming. * For DCN, optimistically query for flip pending immediately after programming, and if it latched, send event right away. v3: * Fix event timestamps on optimistic flip latch detection, where it's possible for it to run *before* the vupdate IRQ updates the timestamp. * Add more docstrings for DCN vblank handling. * Clean up if conditions in dm_arm_vblank_event(). * Code style cleanup on braces surrounding multi-line statements. Fixes: 9b47278cec98 ("drm/amd/display: temp w/a for dGPU to enter idle optimizations") Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/3787 Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/4141 Assisted-by: Copilot:claude-opus-4.8 Tested-by: Mario Limonciello (AMD) Reviewed-by: Mario Limonciello (AMD) Signed-off-by: Leo Li Signed-off-by: Alex Deucher (cherry picked from commit f64a9be5653689ff43e148cd8a6483077488c8e5) Cc: stable@vger.kernel.org # 8382cd234981: drm/amd/display: consolidate DCN vblank/flip handling onto vupdate_no_lock Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin

drm/amd/display: Fix missing DCE check in dm_gpureset_toggle_interrupts()

2026-08-03T09:21:53+00:00

commit fbbaca9e208733652828ea98d00f09f260a7770e upstream. This line was lost when cping from amd-staging-drm-next to drm-fixes. So add it back. Cc: stable@vger.kernel.org Fixes: 8382cd234981 ("drm/amd/display: consolidate DCN vblank/flip handling onto vupdate_no_lock") Reported-by: Lu Yao Signed-off-by: Leo Li Reviewed-by: Mario Limonciello (AMD) Link: https://patch.msgid.link/20260723134450.13838-1-sunpeng.li@amd.com Signed-off-by: Mario Limonciello Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Fix flip-done timeouts on mode1 reset

2026-08-03T09:21:53+00:00

commit 82730dba0cf9d9524af0ceeb7eb6b5c3ab1bdb87 upstream. The vblank on/off callbacks mixed use of amdgpu_irq_get/put() and amdgpu_dm_crtc_set_vupdate_irq() to enable and disable IRQs. With get/put, base driver will callback into DC to disable IRQs when refcount == 0. With set_vupdate_irq(), DC is called directly to disable IRQs, bypassing base driver's refcount tracking. During gpu reset, base driver can restore IRQs via amdgpu_irq_gpu_reset_resume_helper() > amdgpu_irq_update(). So if get/put() is not used (i.e. refcount == 0), then vupdate_irq will be disabled. This is problematic if DRM requests vblank on before amdgpu_irq_update() is called: drm_vblank_on() > set_vupdate_irq() enables vupdate_irq, but the refcount is still 0. gpu_reset_resume_helper() > irq_update() then immediately disables it, thus leading to flip done timeouts. This is made worse on DCN since VUPDATE_NO_LOCK is the only IRQ enabled. Prior to 8382cd234981, a combination of GRPH_FLIP and VSTARTUP IRQs were used, and they used get/put(). This explains why 8382cd234981 exposed this issue. Fix by using get/put() instead of set_vupdate_irq(). DCE is unchanged, since it relies on unbalanced enable/disable calls based on VRR status, and hence requires direct set_vupdate_irq(). Plus, it also uses GRPH_FLIP and VLINE IRQs, which are properly tracked by get/put(). Cc: stable@vger.kernel.org Fixes: 8382cd234981 ("drm/amd/display: consolidate DCN vblank/flip handling onto vupdate_no_lock") Signed-off-by: Leo Li Reviewed-by: Mario Limonciello (AMD) Link: https://patch.msgid.link/20260723180159.52121-1-sunpeng.li@amd.com Signed-off-by: Mario Limonciello Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Fix backlight max_brightness to match exported range

2026-08-03T09:21:52+00:00

commit f1b5d8f9cc54ae8a2567ac126867ae488e1bf625 upstream. [Why] FWTS autobrightness fails on eDP panels because actual_brightness can read higher than the advertised max_brightness (e.g. 63576 vs 62451). The conversion helpers expose the firmware PWM range to userspace as [0..max]. But max_brightness is advertised as (max - min), which is smaller. So reading the level can return a value above max_brightness. This regressed in commit 4b61b8a39051 ("drm/amd/display: Add debugging message for brightness caps"), which changed max_brightness to (max - min) and undid commit 8dbd72cb7900 ("drm/amd/display: Export full brightness range to userspace"). [How] Advertise max_brightness as max, and scale the initial AC/DC brightness against max too. Update the KUnit expectations to match. Fixes: 4b61b8a39051 ("drm/amd/display: Add debugging message for brightness caps") Reviewed-by: Alex Hung Signed-off-by: Mario Limonciello Signed-off-by: George Zhang Signed-off-by: Alex Deucher (cherry picked from commit bd9e2b5b0473c75abc0f4134dfe79ecbfb16610d) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Force PWM backlight on Lenovo Legion 5 15ARH05

2026-08-03T09:21:52+00:00

commit bad177fa75e607e396cd57daaaed881450d7a471 upstream. The Lenovo Legion 5 15ARH05 (Renoir) ships a BOE 0x08DF eDP panel that advertises AUX/DPCD backlight control, so amdgpu's automatic detection (amdgpu_backlight == -1) selects AUX. On this panel the AUX backlight path has no effect: brightness writes are accepted but the panel level never changes, the display is stuck at a fixed brightness and max_brightness is reported as a bogus 511000. As a result neither the desktop brightness slider nor the brightness hotkeys do anything. Forcing PWM backlight (amdgpu.backlight=0) restores working control: max_brightness becomes 65535 and the level tracks writes. This has long been applied by users as a manual kernel-parameter workaround. Extend the generic panel backlight quirk with a force_pwm flag, add an entry for the Legion 5 15ARH05 / BOE 0x08DF panel, and have amdgpu disable AUX backlight (use PWM) when the quirk matches and the user lets the driver auto-select the backlight type. Signed-off-by: Alessandro Rinaldi Tested-by: Alessandro Rinaldi Reviewed-by: George Zhang Signed-off-by: Alex Deucher (cherry picked from commit 81b39f43e7e53589491e2eef6bad5389626b4b9c) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: consolidate DCN vblank/flip handling onto vupdate_no_lock

2026-08-03T09:21:52+00:00

commit 8382cd234981ae36299bb66a10bac2cd8ff1b99d upstream. [Why] On DCN, vblank events were delivered from VSTARTUP/VUPDATE (dm_crtc_high_irq/dm_vupdate_high_irq) and pageflip completion from GRPH_PFLIP (dm_pflip_high_irq). These signals can be masked by hardware by a few things: * DPG - DCN can Dynamically Power Gate parts of the display pipe when a self-refresh capable eDP is connected. DPG is engaged when there's enough static frames (detected through drm_vblank_off). Once gated, even though the OTG (output timing generator) is still enabled, VSTARTUP and GRPH_FLIP are masked. * GSL - Driver can use the Global Sync Lock to block HW from latching onto double-buffered registers during programming, to prevent HW from latching onto a partially programmed state. This will mask VSTARTUP, GRPH_FLIP, and VUPDATE. See dcn20_pipe_control_lock(). * MALL - A DCN accessible cache introduced in DCN32+ DGPUs that can store fb data to allow for longer DRAM sleep. When scanning out from MALL, VSTARTUP is masked. When masked, events are never delivered, which can show up as flip_done timeouts in the wild. However, there is an interrupt source on DCN that is never masked: VUPDATE_NO_LOCK. It's simply an unmasked variant of VUPDATE, which fires while the OTG is active, at the exact point hardware latches double-buffered registers. It is therefore the natural single signal for delivering both vblank and flip-completion events on DCN, and the correct point to timestamp both VRR and non-VRR vblanks. DCE's interrupt sources are different, it does not have an unmaskable VUPDATE_NO_LOCK. The only unmaskable DCE interrupt is VLINE0, but it can only be programmed as a vline offset from vsync_start, making it unsuitable for VRR. Thus, we keep DCE untouched and use the existing mix of interrupt sources. [How] For DCN1 and newer only: * Factor the body of dm_crtc_high_irq() into dm_crtc_high_irq_handler() and drive it from dm_vupdate_high_irq() (VUPDATE_NO_LOCK). DCE keeps using dm_crtc_high_irq() (VSTARTUP) and dm_pflip_high_irq() (GRPH_PFLIP) unchanged. * Stop registering VSTARTUP (crtc_irq) and GRPH_PFLIP (pageflip_irq) on DCN, and stop enabling them in amdgpu_dm_crtc_set_vblank() / manage_dm_interrupts(). Enable VUPDATE whenever vblank is enabled on DCN (previously only in VRR mode). The secure-display vline0 interrupt is left untouched. * VUPDATE_NO_LOCK does not early-fire on an immediate (tearing / async) flip, since HW latches the new address right away. Deliver the flip completion event immediately after programming such flips in amdgpu_dm_commit_planes(), and clear pflip_status so the next vupdate handler does not double-send. v2: Do not gate VUPDATE_NO_LOCK on DCN in dm_handle_vrr_transition() Also toggle VUPDATE_NO_LOCK on DCN in dm_gpureset_toggle_interrupts() Re-cook vblank event count and timestamp for immediate flips Fixes: 9b47278cec98 ("drm/amd/display: temp w/a for dGPU to enter idle optimizations") Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/3787 Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/4141 Assisted-by: Copilot:claude-opus-4.8 Co-developed-by: Matthew Schwartz Signed-off-by: Matthew Schwartz Tested-by: Mario Limonciello (AMD) Reviewed-by: Mario Limonciello (AMD) Signed-off-by: Leo Li Signed-off-by: Alex Deucher (cherry picked from commit c87e6635d2db02c88ae8d09529362da672d34770) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: set new_stream to NULL after release

2026-08-03T09:21:52+00:00

commit 9fa26b9eed6195bf840f39ac183b9a6237548755 upstream. In dm_update_crtc_state(), the skip_modeset path releases new_stream via dc_stream_release() but does not set the pointer to NULL. If a later error (e.g., color management failure) triggers the fail label, the error path calls dc_stream_release() again on the same dangling pointer, causing a double release and potential use-after-free. Fix this by setting new_stream to NULL after the initial release. Fixes: 9b690ef3c704 ("drm/amd/display: Avoid full modeset when not required") Signed-off-by: WenTao Liang Reviewed-by: George Zhang Signed-off-by: Alex Deucher (cherry picked from commit 99f3af19073b3ddbfd96e789124cce12c4277b28) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman