kernel/linux.git/drivers/gpu/drm/amd/display, branch v6.6.142

drm/amd/display: Validate payload length and link_index in dc_process_dmub_aux_transfer_async

2026-06-01T15:43:09+00:00

commit 6c92f6d9600efa3ef0d9e560a2b52776d9803c29 upstream. [Why&How] dc_process_dmub_aux_transfer_async() copies payload->length bytes into a 16-byte stack buffer (dpaux.data[16]) guarded only by an ASSERT(), which is a no-op in release builds. If a caller ever passes length > 16 this results in a stack buffer overflow via memcpy. Additionally, link_index is used to dereference dc->links[] without bounds checking against dc->link_count, risking an out-of-bounds access. Replace the ASSERT with a hard runtime check that returns false when payload->length exceeds the destination buffer size, and add a bounds check for link_index before it is used. Assisted-by: GitHub Copilot:Claude claude-4-opus Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit ba4caa9fecdf7a38f98c878ad05a8a64148b6881) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Validate GPIO pin LUT table size before iterating

2026-06-01T15:43:09+00:00

commit 86d2b20644b11d21fe52c596e6e922b4590a3e3f upstream. [Why&How] The GPIO pin table parsers in get_gpio_i2c_info() and bios_parser_get_gpio_pin_info() derive an element count from the VBIOS table_header.structuresize field, then iterate over gpio_pin[] entries. However, GET_IMAGE() only validates that the table header itself fits within the BIOS image. If the VBIOS reports a structuresize larger than the actual mapped data, the loop reads past the end of the BIOS image, causing an out-of-bounds read. Fix this by calling bios_get_image() to validate that the full claimed structuresize is accessible within the BIOS image before entering the loop in both functions. Assisted-by: GitHub Copilot:claude-opus-4-6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit ba5e95b43b773ae1bf1f66ee6b31eb774e65afe3) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Fix integer overflow in bios_get_image()

2026-06-01T15:43:09+00:00

commit cd86529ec61474a38c3837fb7823790a7c3f8cce upstream. [Why&How] The bounds check in bios_get_image() computes 'offset + size' using unsigned 32-bit arithmetic before comparing against bios_size. If a VBIOS image contains a near-UINT32_MAX offset the addition wraps to a small value, the comparison passes, and the function returns a wild pointer past the VBIOS mapping. Additionally, the comparison uses '<' (strict), which incorrectly rejects the valid exact-fit case where offset + size == bios_size. Fix both issues by restructuring the check to avoid the addition entirely: first reject if offset alone exceeds bios_size, then check size against the remaining space (bios_size - offset). This eliminates the overflow and correctly permits exact-fit accesses. Assisted-by: GitHub Copilot:claude-opus-4.6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit d40fb392af659c4a02b560319f226842f6ec1a95) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Read EDID from VBIOS embedded panel info

2026-05-23T11:03:30+00:00

[ Upstream commit 9ea16f64189bf7b6ba50fc7f0325b3c1f836d105 ] Some board manufacturers hardcode the EDID for the embedded panel in the VBIOS. This EDID should be used when the panel doesn't have a DDC. For reference, see the legacy non-DC display code: amdgpu_atombios_encoder_get_lcd_info() This is necessary to support embedded connectors without DDC. Fixes: 4562236b3bc0 ("drm/amd/dc: Add dc display driver (v2)") Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/5192 Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher (cherry picked from commit eb105e63b474c11ef6a84a1c6b18100d851ff364) Signed-off-by: Sasha Levin

drm/amd/display: Allow DCE link encoder without AUX registers

2026-05-23T11:03:30+00:00

[ Upstream commit ac27e3f99035f132f23bc0409d0e57f11f054c70 ] Allow constructing the DCE link encoder without DDC, which means the AUX registers array will be NULL. This is necessary to support embedded connectors without DDC. Fixes: 4562236b3bc0 ("drm/amd/dc: Add dc display driver (v2)") Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/5192 Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher (cherry picked from commit 87f30b101af62590faf6020d106da07efdda199b) Signed-off-by: Sasha Levin

drm/amd/display: Do not skip unrelated mode changes in DSC validation

2026-05-17T15:13:35+00:00

[ Upstream commit aed3d041ab061ec8a64f50a3edda0f4db7280025 ] Starting with commit 17ce8a6907f7 ("drm/amd/display: Add dsc pre-validation in atomic check"), amdgpu resets the CRTC state mode_changed flag to false when recomputing the DSC configuration results in no timing change for a particular stream. However, this is incorrect in scenarios where a change in MST/DSC configuration happens in the same KMS commit as another (unrelated) mode change. For example, the integrated panel of a laptop may be configured differently (e.g., HDR enabled/disabled) depending on whether external screens are attached. In this case, plugging in external DP-MST screens may result in the mode_changed flag being dropped incorrectly for the integrated panel if its DSC configuration did not change during precomputation in pre_validate_dsc(). At this point, however, dm_update_crtc_state() has already created new streams for CRTCs with DSC-independent mode changes. In turn, amdgpu_dm_commit_streams() will never release the old stream, resulting in a memory leak. amdgpu_dm_atomic_commit_tail() will never acquire a reference to the new stream either, which manifests as a use-after-free when the stream gets disabled later on: BUG: KASAN: use-after-free in dc_stream_release+0x25/0x90 [amdgpu] Write of size 4 at addr ffff88813d836524 by task kworker/9:9/29977 Workqueue: events drm_mode_rmfb_work_fn Call Trace: dump_stack_lvl+0x6e/0xa0 print_address_description.constprop.0+0x88/0x320 ? dc_stream_release+0x25/0x90 [amdgpu] print_report+0xfc/0x1ff ? srso_alias_return_thunk+0x5/0xfbef5 ? __virt_addr_valid+0x225/0x4e0 ? dc_stream_release+0x25/0x90 [amdgpu] kasan_report+0xe1/0x180 ? dc_stream_release+0x25/0x90 [amdgpu] kasan_check_range+0x125/0x200 dc_stream_release+0x25/0x90 [amdgpu] dc_state_destruct+0x14d/0x5c0 [amdgpu] dc_state_release.part.0+0x4e/0x130 [amdgpu] dm_atomic_destroy_state+0x3f/0x70 [amdgpu] drm_atomic_state_default_clear+0x8ee/0xf30 ? drm_mode_object_put.part.0+0xb1/0x130 __drm_atomic_state_free+0x15c/0x2d0 atomic_remove_fb+0x67e/0x980 Since there is no reliable way of figuring out whether a CRTC has unrelated mode changes pending at the time of DSC validation, remember the value of the mode_changed flag from before the point where a CRTC was marked as potentially affected by a change in DSC configuration. Reset the mode_changed flag to this earlier value instead in pre_validate_dsc(). Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/5004 Fixes: 17ce8a6907f7 ("drm/amd/display: Add dsc pre-validation in atomic check") Signed-off-by: Yussuf Khalil Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher (cherry picked from commit cc7c7121ae082b7b82891baa7280f1ff2608f22b) Signed-off-by: Fang Wang <32840572@qq.com> Signed-off-by: Sasha Levin

drm/amd/display: Fix DisplayID not-found handling in parse_edid_displayid_vrr()

2026-03-25T10:06:10+00:00

[ Upstream commit 2323b019651ad81c20a0f7f817c63392b3110652 ] parse_edid_displayid_vrr() searches the EDID extension blocks for a DisplayID extension before parsing the dynamic video timing range. The code previously checked whether edid_ext was NULL after the search loop. However, edid_ext is assigned during each iteration of the loop, so it will never be NULL once the loop has executed. If no DisplayID extension is found, edid_ext ends up pointing to the last extension block, and the NULL check does not correctly detect the failure case. Instead, check whether the loop completed without finding a matching DisplayID block by testing "i == edid->extensions". This ensures the function exits early when no DisplayID extension is present and avoids parsing an unrelated EDID extension block. Also simplify the EDID validation check using "!edid || !edid->extensions". Fixes the below: drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:13079 parse_edid_displayid_vrr() warn: variable dereferenced before check 'edid_ext' (see line 13075) Fixes: a638b837d0e6 ("drm/amd/display: Fix refresh rate range for some panel") Cc: Roman Li Cc: Alex Hung Cc: Jerry Zuo Cc: Sun peng Li Cc: Tom Chung Cc: Dan Carpenter Cc: Aurabindo Pillai Signed-off-by: Srinivasan Shanmugam Reviewed-by: Tom Chung Signed-off-by: Alex Deucher (cherry picked from commit 91c7e6342e98c846b259c57273436fdea4c043f2) Signed-off-by: Sasha Levin

drm/amd/display: Wrap dcn32_override_min_req_memclk() in DC_FP_{START, END}

2026-03-25T10:06:05+00:00

commit ebe82c6e75cfc547154d0fd843b0dd6cca3d548f upstream. [Why] The dcn32_override_min_req_memclk function is in dcn32_fpu.c, which is compiled with CC_FLAGS_FPU into FP instructions. So when we call it we must use DC_FP_{START,END} to save and restore the FP context, and prepare the FP unit on architectures like LoongArch where the FP unit isn't always on. Reported-by: LiarOnce Fixes: ee7be8f3de1c ("drm/amd/display: Limit DCN32 8 channel or less parts to DPM1 for FPO") Signed-off-by: Xi Ruoyao Reviewed-by: Alex Hung Signed-off-by: Alex Deucher (cherry picked from commit 25bb1d54ba3983c064361033a8ec15474fece37e) Cc: stable@vger.kernel.org [ dropped missing `dcn32_override_min_req_dcfclk()` call since ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Add pixel_clock to amd_pp_display_configuration

2026-03-25T10:06:00+00:00

commit b515dcb0dc4e85d8254f5459cfb32fce88dacbfb upstream. This commit adds the pixel_clock field to the display config struct so that power management (DPM) can use it. We currently don't have a proper bandwidth calculation on old GPUs with DCE 6-10 because dce_calcs only supports DCE 11+. So the power management (DPM) on these GPUs may need to make ad-hoc decisions for display based on the pixel clock. Also rename sym_clock to pixel_clock in dm_pp_single_disp_config to avoid confusion with other code where the sym_clock refers to the DisplayPort symbol clock. Signed-off-by: Timur Kristóf Signed-off-by: Alex Deucher Signed-off-by: Rosen Penev Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Use GFP_ATOMIC in dc_create_stream_for_sink

2026-03-25T10:05:56+00:00

[ Upstream commit 28dfe4317541e57fe52f9a290394cd29c348228b ] This can be called while preemption is disabled, for example by dcn32_internal_validate_bw which is called with the FPU active. Fixes "BUG: scheduling while atomic" messages I encounter on my Navi31 machine. Signed-off-by: Natalie Vock Signed-off-by: Alex Deucher (cherry picked from commit b42dae2ebc5c84a68de63ec4ffdfec49362d53f1) Cc: stable@vger.kernel.org [ Context ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman