From 94cf5971b1d04c6382437387c4dc3836cc7a1437 Mon Sep 17 00:00:00 2001 From: Fan Wu Date: Tue, 15 Sep 2026 09:51:03 +0000 Subject: [PATCH 01/15] drm/vc4: drain the hangcheck timer and works on V3D unbind MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Nothing stops the hangcheck timer that submitted jobs arm, or the job_done_work that the render-done interrupt queues, at teardown: vc4_irq_disable() cancels only overflow_mem_work, and vc4_gem_destroy() runs from the drm-managed release, after vc4_v3d_unbind() has already uninstalled the V3D interrupt and cleared vc4->v3d. A timer still armed by then reads V3D registers through the NULL vc4->v3d pointer, and the late callbacks run on the vc4_dev embedding them after it has been freed. Drain them in vc4_v3d_unbind(): shut the timer down and cancel reset_work before the interrupt is taken down, because its vc4_irq_reset() re-enables it, then flush job_done_work so that completions queued at teardown still release their jobs. This issue was found by an in-house static analysis tool. Fixes: d5b1a78a772f ("drm/vc4: Add support for drawing 3D frames.") Cc: stable@vger.kernel.org # 6.2+ Assisted-by: Codex:gpt-5.6 Co-developed-by: Song Li Signed-off-by: Song Li Signed-off-by: Fan Wu Link: https://patch.msgid.link/20260915095103.156007-1-fanwu01@zju.edu.cn Reviewed-by: Maíra Canal Signed-off-by: Maíra Canal --- drivers/gpu/drm/vc4/vc4_v3d.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c index f32410420d3e..0f0c090afa6e 100644 --- a/drivers/gpu/drm/vc4/vc4_v3d.c +++ b/drivers/gpu/drm/vc4/vc4_v3d.c @@ -9,6 +9,7 @@ #include #include #include +#include #include @@ -497,8 +498,15 @@ static void vc4_v3d_unbind(struct device *dev, struct device *master, struct drm_device *drm = data; struct vc4_dev *vc4 = to_vc4_dev(drm); + /* A straggler vc4_reset() re-enables the interrupt. */ + timer_shutdown_sync(&vc4->hangcheck.timer); + cancel_work_sync(&vc4->hangcheck.reset_work); + vc4_irq_uninstall(drm); + /* Flush rather than cancel, so queued completions release their jobs. */ + flush_work(&vc4->job_done_work); + /* Disable the binner's overflow memory address, so the next * driver probe (if any) doesn't try to reuse our old * allocation. From b816da5d5df1461446a0a5f3fe2b4948a659a790 Mon Sep 17 00:00:00 2001 From: Wentao Liang Date: Wed, 16 Sep 2026 15:40:15 +0000 Subject: [PATCH 02/15] drm/vc4: Fix firmware reference leak in vc4_drm_bind() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The firmware reference obtained via rpi_firmware_get() is leaked when aperture_remove_all_conflicting_devices() fails, as the error label returns without putting it. This happens before the firmware is consumed and put further down in the function. Put the firmware reference before jumping to err. Fixes: c406ad5e4a85 ("drm/vc4: Notify the firmware when DRM is in charge") Cc: stable@vger.kernel.org Signed-off-by: Wentao Liang Link: https://patch.msgid.link/20260916154015.2056797-1-vulab@iscas.ac.cn Reviewed-by: Maíra Canal Signed-off-by: Maíra Canal --- drivers/gpu/drm/vc4/vc4_drv.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index 616caf9d9915..7b64e1ed02d4 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -360,8 +360,11 @@ static int vc4_drm_bind(struct device *dev) } ret = aperture_remove_all_conflicting_devices(driver->name); - if (ret) + if (ret) { + if (firmware) + rpi_firmware_put(firmware); goto err; + } if (firmware) { ret = rpi_firmware_property(firmware, From add916cfcec5b71cb242db85b91b2437be7390cf Mon Sep 17 00:00:00 2001 From: Felix Gu Date: Sat, 21 Mar 2026 03:12:10 +0800 Subject: [PATCH 03/15] drm/bridge: th1520-dw-hdmi: Fix error check on dw_hdmi_probe() return value The error check after calling dw_hdmi_probe() was incorrectly checking the struct pointer hdmi instead of the probe result hdmi->dw_hdmi. Fix this by checking the correct variable. Fixes: 96f30ee0fb9d ("drm/bridge: add a driver for T-Head TH1520 HDMI controller") Signed-off-by: Felix Gu Reviewed-by: Dmitry Baryshkov Cc: stable@vger.kernel.org Signed-off-by: Icenowy Zheng Link: https://patch.msgid.link/20260321-th1520-v1-1-ec877197770d@gmail.com --- drivers/gpu/drm/bridge/th1520-dw-hdmi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/bridge/th1520-dw-hdmi.c b/drivers/gpu/drm/bridge/th1520-dw-hdmi.c index cbea8b14cd4b..3464720b4e13 100644 --- a/drivers/gpu/drm/bridge/th1520-dw-hdmi.c +++ b/drivers/gpu/drm/bridge/th1520-dw-hdmi.c @@ -135,8 +135,8 @@ static int th1520_dw_hdmi_probe(struct platform_device *pdev) plat_data->priv_data = hdmi; hdmi->dw_hdmi = dw_hdmi_probe(pdev, plat_data); - if (IS_ERR(hdmi)) - return PTR_ERR(hdmi); + if (IS_ERR(hdmi->dw_hdmi)) + return PTR_ERR(hdmi->dw_hdmi); platform_set_drvdata(pdev, hdmi); From 01c83795d50ccdb441f60e89ff50767cb2f6045a Mon Sep 17 00:00:00 2001 From: Felix Gu Date: Sat, 21 Mar 2026 03:12:11 +0800 Subject: [PATCH 04/15] drm/bridge: th1520-dw-hdmi: Fix remove() callback This driver stores struct th1520_hdmi * in platform drvdata, but th1520_dw_hdmi_remove() was reading it back as struct dw_hdmi * and passing it to dw_hdmi_remove(), so teardown runs on the wrong pointer. Retrieve struct th1520_hdmi * from platform drvdata and pass hdmi->dw_hdmi to dw_hdmi_remove(). Fixes: 96f30ee0fb9d ("drm/bridge: add a driver for T-Head TH1520 HDMI controller") Signed-off-by: Felix Gu Reviewed-by: Dmitry Baryshkov Cc: stable@vger.kernel.org Signed-off-by: Icenowy Zheng Link: https://patch.msgid.link/20260321-th1520-v1-2-ec877197770d@gmail.com --- drivers/gpu/drm/bridge/th1520-dw-hdmi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/bridge/th1520-dw-hdmi.c b/drivers/gpu/drm/bridge/th1520-dw-hdmi.c index 3464720b4e13..2fa7f2d46b3d 100644 --- a/drivers/gpu/drm/bridge/th1520-dw-hdmi.c +++ b/drivers/gpu/drm/bridge/th1520-dw-hdmi.c @@ -145,9 +145,9 @@ static int th1520_dw_hdmi_probe(struct platform_device *pdev) static void th1520_dw_hdmi_remove(struct platform_device *pdev) { - struct dw_hdmi *hdmi = platform_get_drvdata(pdev); + struct th1520_hdmi *hdmi = platform_get_drvdata(pdev); - dw_hdmi_remove(hdmi); + dw_hdmi_remove(hdmi->dw_hdmi); } static const struct of_device_id th1520_dw_hdmi_of_table[] = { From 21bc51cb89ced74d6645a138cc2f21184bc75094 Mon Sep 17 00:00:00 2001 From: Zack Rusin Date: Sun, 9 Aug 2026 16:45:15 -0400 Subject: [PATCH 05/15] drm/vmwgfx: validate pitch coming from userspace Validate the pitch, alongside the box dimensions before trying to copy data from the underlying surface. Fixes possible out of bounds reads with cursor snooping. Fixes: 2ac863719e51 ("vmwgfx: Snoop DMA transfers with non-covering sizes") Cc: stable@vger.kernel.org Reported-by: Youness HFA Signed-off-by: Zack Rusin Reviewed-by: Maaz Mombasawala Link: https://patch.msgid.link/20260809204515.211045-1-zack.rusin@broadcom.com --- drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c | 26 ++++++++++++++++---- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c b/drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c index d1e7df500190..5a69606a0593 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_cursor_plane.c @@ -324,6 +324,7 @@ void vmw_kms_cursor_snoop(struct vmw_surface *srf, unsigned long kmap_num; SVGA3dCopyBox *box; u32 box_count; + u64 src_extent; void *virtual; bool is_iomem; struct vmw_dma_cmd { @@ -335,6 +336,8 @@ void vmw_kms_cursor_snoop(struct vmw_surface *srf, vmw_surface_get_desc(VMW_CURSOR_SNOOP_FORMAT); const u32 image_pitch = VMW_CURSOR_SNOOP_WIDTH * desc->pitchBytesPerBlock; + BUILD_BUG_ON(sizeof(*srf->snooper.image) != desc->pitchBytesPerBlock); + cmd = container_of(header, struct vmw_dma_cmd, header); /* No snooper installed, nothing to copy */ @@ -372,8 +375,19 @@ void vmw_kms_cursor_snoop(struct vmw_surface *srf, return; } + if (box->w == 0 || box->h == 0) + return; + + src_extent = (u64)(box->h - 1) * cmd->dma.guest.pitch + + (u64)box->w * desc->pitchBytesPerBlock; + if (src_extent > bo->base.size) { + DRM_ERROR("Cursor snoop source of %llu bytes exceeds the %zu byte buffer\n", + src_extent, bo->base.size); + return; + } + kmap_offset = cmd->dma.guest.ptr.offset >> PAGE_SHIFT; - kmap_num = (VMW_CURSOR_SNOOP_HEIGHT * image_pitch) >> PAGE_SHIFT; + kmap_num = PFN_UP(src_extent); ret = ttm_bo_reserve(bo, true, false, NULL); if (unlikely(ret != 0)) { @@ -387,14 +401,16 @@ void vmw_kms_cursor_snoop(struct vmw_surface *srf, virtual = ttm_kmap_obj_virtual(&map, &is_iomem); - if (box->w == VMW_CURSOR_SNOOP_WIDTH && cmd->dma.guest.pitch == image_pitch) { + if (box->w == VMW_CURSOR_SNOOP_WIDTH && + box->h == VMW_CURSOR_SNOOP_HEIGHT && + cmd->dma.guest.pitch == image_pitch) { memcpy(srf->snooper.image, virtual, VMW_CURSOR_SNOOP_HEIGHT * image_pitch); } else { - /* Image is unsigned pointer. */ + /* The destination stride is in pixels. */ for (i = 0; i < box->h; i++) - memcpy(srf->snooper.image + i * image_pitch, - virtual + i * cmd->dma.guest.pitch, + memcpy(srf->snooper.image + i * VMW_CURSOR_SNOOP_WIDTH, + virtual + (size_t)i * cmd->dma.guest.pitch, box->w * desc->pitchBytesPerBlock); } srf->snooper.id++; From e78a9fb7a40c55ec2a70ae39903dde4f898af2ef Mon Sep 17 00:00:00 2001 From: Ian Forbes Date: Wed, 16 Sep 2026 14:01:44 -0500 Subject: [PATCH 06/15] drm/vmwgfx: Add blend mode property This stops the log spamming introduced by the referenced fixes commit. Fixes: 860e748bddcc ("drm: ensure blend mode supported if pixel format with alpha exposed") Signed-off-by: Ian Forbes Reviewed-by: Zack Rusin Signed-off-by: Zack Rusin Link: https://patch.msgid.link/20260916190144.2080777-1-ian.forbes@broadcom.com --- drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c index 1b407b61f683..31d3ee0825ca 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c @@ -20,10 +20,18 @@ #include #include #include +#include void vmw_du_init(struct vmw_display_unit *du) { vmw_vkms_crtc_init(&du->crtc); + drm_plane_create_blend_mode_property(&du->primary, + BIT(DRM_MODE_BLEND_PIXEL_NONE) | + BIT(DRM_MODE_BLEND_PREMULTI)); + // Check that the cursor plane was actually initialized + if (du->crtc.cursor == &du->cursor.base) + drm_plane_create_blend_mode_property(&du->cursor.base, + BIT(DRM_MODE_BLEND_PREMULTI)); } void vmw_du_cleanup(struct vmw_display_unit *du) From b62e3db8cdc1680e1c3390591e872f485148541a Mon Sep 17 00:00:00 2001 From: Cristian Ciocaltea Date: Tue, 1 Sep 2026 21:50:36 +0300 Subject: [PATCH 07/15] drm/bridge: Fix unlocked list_del in drm_bridge_add() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When re-adding a bridge that was previously removed, drm_bridge_add() drops it from bridge_lingering_list without holding bridge_lock. Both bridge_list and bridge_lingering_list are protected by bridge_lock, as they are concurrently modified by drm_bridge_remove() and __drm_bridge_free(), and walked by the debugfs 'bridges' file. Running the list_empty() test and the list_del_init() outside of the lock may therefore corrupt either list. Perform both under bridge_lock. Fixes: 17805a15d175 ("drm/bridge: add list of removed refcounted bridges") Reported-by: Sashiko Closes: https://lore.kernel.org/all/20260723015004.1F5711F000E9@smtp.kernel.org/ Signed-off-by: Cristian Ciocaltea Reviewed-by: Luca Ceresoli Tested-by: Luca Ceresoli Tested-by: Igor Paunovic # RK3588 Orange Pi 5 Plus, dual HDMI Tested-by: Robin Räber Link: https://patch.msgid.link/20260901-dw-hdmi-qp-scramb-v11-12-bc12954a0688@collabora.com Signed-off-by: Luca Ceresoli --- drivers/gpu/drm/drm_bridge.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 83f1809a5d37..04b999305f30 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -454,8 +454,10 @@ void drm_bridge_add(struct drm_bridge *bridge) * in bridge_lingering_list. Remove it or bridge_lingering_list will be * corrupted when adding this bridge to bridge_list below. */ + mutex_lock(&bridge_lock); if (!list_empty(&bridge->list)) list_del_init(&bridge->list); + mutex_unlock(&bridge_lock); mutex_init(&bridge->hpd_state_mutex); mutex_init(&bridge->hpd_mutex); From 57889076afd1be890150c32ffde3b691fe5707c8 Mon Sep 17 00:00:00 2001 From: Cristian Ciocaltea Date: Tue, 1 Sep 2026 21:50:38 +0300 Subject: [PATCH 08/15] drm/bridge: Fix unlocked list access in drm_bridge_attach() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit drm_bridge_attach() inspects bridge->list to warn about bridges being attached without a previous drm_bridge_add() call, but it does so without holding bridge_lock. The list head can be concurrently written by drm_bridge_add(), drm_bridge_remove() and __drm_bridge_free() while they operate on neighbouring entries of bridge_list or bridge_lingering_list, all of them under bridge_lock. Hence the unlocked read is a data race, even though it is unlikely to change the outcome of list_empty() in practice. Perform the check with bridge_lock held. Fixes: 76f1a9711b83 ("drm/bridge: add warning for bridges attached without being added") Signed-off-by: Cristian Ciocaltea Reviewed-by: Luca Ceresoli Tested-by: Luca Ceresoli Tested-by: Igor Paunovic # RK3588 Orange Pi 5 Plus, dual HDMI Tested-by: Robin Räber Link: https://patch.msgid.link/20260901-dw-hdmi-qp-scramb-v11-14-bc12954a0688@collabora.com Signed-off-by: Luca Ceresoli --- drivers/gpu/drm/drm_bridge.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 04b999305f30..a52d5f5b9f05 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -595,8 +595,10 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge, if (!bridge->container) DRM_WARN("DRM bridge corrupted or not allocated by devm_drm_bridge_alloc()\n"); - if (list_empty(&bridge->list)) - DRM_WARN("Missing drm_bridge_add() before attach\n"); + scoped_guard(mutex, &bridge_lock) { + if (list_empty(&bridge->list)) + DRM_WARN("Missing drm_bridge_add() before attach\n"); + } drm_bridge_get(bridge); From ec86c43dcfff68eab4db9bdafcd3e2b16e342e18 Mon Sep 17 00:00:00 2001 From: Osama Abdelkader Date: Tue, 4 Aug 2026 18:00:47 +0200 Subject: [PATCH 09/15] drm/panthor: validate userspace queue count against initialized firmware slot count In panthor_drv.c:panthor_ioctl_group_create(), the queue count is validated against the hardcoded maximum: if (!args->queues.count || args->queues.count > MAX_CS_PER_CSG) return -EINVAL; However, if the firmware reports fewer slots than MAX_CS_PER_CSG, panthor_fw_init_ifaces() will only initialize that smaller number of stream interfaces. If unprivileged userspace requests more queues than the firmware reported (but no more than MAX_CS_PER_CSG), cs_slot_prog_locked() fetches an uninitialized stream interface and may crash when dereferencing cs_iface->input->ringbuf_base. Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block") Cc: stable@vger.kernel.org Reported-by: sashiko-bot@kernel.org Closes: https://sashiko.dev/#/patchset/20260803141149.68182-1-osama.abdelkader@gmail.com?part=1 Signed-off-by: Osama Abdelkader Reviewed-by: Steven Price Reviewed-by: Liviu Dudau Reviewed-by: Boris Brezillon Link: https://patch.msgid.link/20260804160048.174148-1-osama.abdelkader@gmail.com Signed-off-by: Steven Price --- drivers/gpu/drm/panthor/panthor_sched.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c index 5778e23e20a0..653c6755896c 100644 --- a/drivers/gpu/drm/panthor/panthor_sched.c +++ b/drivers/gpu/drm/panthor/panthor_sched.c @@ -3674,6 +3674,9 @@ int panthor_group_create(struct panthor_file *pfile, hweight64(group_args->tiler_core_mask) < group_args->max_tiler_cores) return -EINVAL; + if (group_args->queues.count > sched->cs_slot_count) + return -EINVAL; + group = kzalloc_obj(*group); if (!group) return -ENOMEM; From 707ce102521496c67860d81221b20c56d8255f2f Mon Sep 17 00:00:00 2001 From: Oleg Keri Date: Fri, 25 Sep 2026 15:25:58 +0200 Subject: [PATCH 10/15] drm/dp: don't mark the AUX backlight enabled when enabling failed If drm_edp_backlight_enable() fails, dp_aux_backlight_update_status() still marks the backlight as enabled. From then on every brightness change only updates the level and the enable is never retried, so the panel stays dark until something blanks and unblanks the backlight. Return the error instead, so the next update tries to enable again. Fixes: 10f7b40e4f30 ("drm/panel: add basic DP AUX backlight support") Signed-off-by: Oleg Keri Reviewed-by: Douglas Anderson Signed-off-by: Douglas Anderson Link: https://patch.msgid.link/20260925132558.27518-1-okerixx@gmail.com --- drivers/gpu/drm/display/drm_dp_helper.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index e623ccb4c1d8..488fd123a01a 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -4634,7 +4634,9 @@ static int dp_aux_backlight_update_status(struct backlight_device *bd) if (!backlight_is_blank(bd)) { if (!bl->enabled) { - drm_edp_backlight_enable(bl->aux, &bl->info, brightness); + ret = drm_edp_backlight_enable(bl->aux, &bl->info, brightness); + if (ret) + return ret; bl->enabled = true; return 0; } From 4d0e2704118511e37790641d591454354e7c0d6c Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Wed, 30 Sep 2026 17:36:15 +1000 Subject: [PATCH 11/15] nouveau: check gsp->rm as well as gsp pointer before gcx ready In turing systems where gsp exists, but can end up not being used, we need to add a second check. Fixes: cb4c7603678c ("drm/nouveau/gsp/r570: Add support for INTERNAL_GCX_ENTRY_PREREQUISITE") Reported-by: Woody Suwalski Tested-by: Woody Suwalski Reviewed-by: Lyude Paul Signed-off-by: Dave Airlie Link: https://lore.kernel.org/nouveau/20260930212151.3926202-1-airlied@gmail.com/T/#u --- drivers/gpu/drm/nouveau/nvkm/engine/device/user.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/device/user.c b/drivers/gpu/drm/nouveau/nvkm/engine/device/user.c index f78e6b9b4292..b841d66f8bb3 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/device/user.c +++ b/drivers/gpu/drm/nouveau/nvkm/engine/device/user.c @@ -201,7 +201,7 @@ nvkm_udevice_gcx_ready(struct nvkm_udevice *udev, void *data, u32 size) } *args = data; int ret = -ENOSYS; - if (!gsp) { + if (!gsp || !gsp->rm) { args->v0.ready = NV_DEVICE_GC6_READY | NV_DEVICE_GCOFF_READY; return 0; } From 755c94d178b7e972bb766199d34e4ba4f63a89eb Mon Sep 17 00:00:00 2001 From: Nguyen Ngoc Thang Date: Sun, 27 Sep 2026 14:54:34 +0700 Subject: [PATCH 12/15] drm/fb-helper: defer setup when fbdev_probe() fails, not just on -EAGAIN __drm_fb_helper_initial_config_and_unlock() calls drm_client_modeset_probe() first, which already fills in each mode_set->mode/num_connectors for every connected output, and only afterwards calls drm_fb_helper_single_fb_probe() to create fb_helper->fb and wire it into those mode_sets via drm_setup_crtcs_fb(). If drm_fb_helper_single_fb_probe() fails with anything other than -EAGAIN (e.g. dev->driver->fbdev_probe() itself fails), the function bails out before drm_setup_crtcs_fb() runs and before setting fb_helper->deferred_setup. The client is left with mode_sets that have a mode and connectors but mode_set->fb == NULL, and nothing marks this fb_helper as needing a retry. __drm_fb_helper_restore_fbdev_mode_unlocked() only skips committing when fb_helper->deferred_setup is set, so a later .restore() call (drm_lastclose() on process exit, in this report) commits the stale mode_set through drm_client_modeset_commit() -> drm_client_modeset_commit_atomic() -> __drm_atomic_helper_set_config(), which hits WARN_ON(!set->fb). Mark fb_helper->deferred_setup on any drm_fb_helper_single_fb_probe() failure, not just -EAGAIN, so restore keeps skipping the commit until a later hotplug event successfully re-probes and re-populates mode_set->fb. The real error code is still returned to the caller unchanged. Reported-by: syzbot+ca23c8570669ead78867@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=ca23c8570669ead78867 Fixes: ca91a2758fce ("drm/fb-helper: Support deferred setup") Cc: stable@vger.kernel.org Signed-off-by: Nguyen Ngoc Thang Signed-off-by: Thomas Zimmermann Link: https://patch.msgid.link/20260927075434.72658-1-ngocthang2710.1999@gmail.com Link: https://patch.msgid.link/20260917154743.1621-1-shechenglong@xfusion.com --- drivers/gpu/drm/drm_fb_helper.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index d4664ed468b2..0817b639b3fa 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1724,10 +1724,10 @@ __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper) ret = drm_fb_helper_single_fb_probe(fb_helper); if (ret < 0) { - if (ret == -EAGAIN) { - fb_helper->deferred_setup = true; + /* modesets are probed but fb_helper->fb isn't; defer restore too */ + fb_helper->deferred_setup = true; + if (ret == -EAGAIN) ret = 0; - } mutex_unlock(&fb_helper->lock); goto err_drm_fb_helper_release_info; From ecce445c6489895463b7ddec2af66338287fee4c Mon Sep 17 00:00:00 2001 From: Myeonghun Pak Date: Sun, 13 Sep 2026 18:30:19 -0400 Subject: [PATCH 13/15] drm/aspeed: Balance the display clock enable on teardown aspeed_gfx_load() enables the display clock without checking the return value and never disables it on probe failure or removal. devm_clk_get() only releases the clock reference, leaving the enable unbalanced. Use devm_clk_get_enabled() to handle enable failures and automatically disable and unprepare the clock on probe failure or removal. This issue was identified during our ongoing static-analysis research while reviewing kernel code. Fixes: 4f2a8f5898ec ("drm: Add ASPEED GFX driver") Co-developed-by: Ijae Kim Signed-off-by: Ijae Kim Signed-off-by: Myeonghun Pak Assisted-by: OpenAI:GPT-5.6 Reviewed-by: Thomas Zimmermann Signed-off-by: Thomas Zimmermann Link: https://patch.msgid.link/20260913223019.89651-1-mhun512@gmail.com Link: https://patch.msgid.link/20260905080426.34224-1-kmehltretter@gmail.com --- drivers/gpu/drm/aspeed/aspeed_gfx_drv.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c b/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c index d4577663a1f0..aa36b79d0f6c 100644 --- a/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c +++ b/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c @@ -189,13 +189,12 @@ static int aspeed_gfx_load(struct drm_device *drm) } reset_control_deassert(priv->rst); - priv->clk = devm_clk_get(drm->dev, NULL); + priv->clk = devm_clk_get_enabled(drm->dev, NULL); if (IS_ERR(priv->clk)) { dev_err(&pdev->dev, - "missing or invalid clk device tree entry"); + "failed to get and enable clock\n"); return PTR_ERR(priv->clk); } - clk_prepare_enable(priv->clk); /* Sanitize control registers */ writel(0, priv->base + CRT_CTRL1); From b41ff8b529278216cba22a5dcdc93fea2a3a9619 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ma=C3=ADra=20Canal?= Date: Wed, 30 Sep 2026 16:06:50 -0300 Subject: [PATCH 14/15] drm/vc4: Free the BO cache size list on teardown MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit vc4_bo_cache_destroy() purges the cached BOs but never frees the size list, leaking it on every unbind. Fixes: c826a6e10644 ("drm/vc4: Add a BO cache.") Assisted-by: LLM Reviewed-by: Thadeu Lima de Souza Cascardo Link: https://patch.msgid.link/20260930190721.1897264-1-mcanal@igalia.com Signed-off-by: Maíra Canal --- drivers/gpu/drm/vc4/vc4_bo.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/vc4/vc4_bo.c b/drivers/gpu/drm/vc4/vc4_bo.c index 49ea2ed0996b..ea1be891ac78 100644 --- a/drivers/gpu/drm/vc4/vc4_bo.c +++ b/drivers/gpu/drm/vc4/vc4_bo.c @@ -1052,6 +1052,7 @@ static void vc4_bo_cache_destroy(struct drm_device *dev, void *unused) cancel_work_sync(&vc4->bo_cache.time_work); vc4_bo_cache_purge(dev); + kfree(vc4->bo_cache.size_list); for (i = 0; i < vc4->num_labels; i++) { if (vc4->bo_labels[i].num_allocated) { From bca45af5998a05f34b13a2ef11e639bac9c62643 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ma=C3=ADra=20Canal?= Date: Wed, 30 Sep 2026 16:06:51 -0300 Subject: [PATCH 15/15] drm/vc4: Use kvmalloc_objs() for the BO cache size list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The BO cache size list has one entry per BO page count, so its size scales with the largest BO ever freed. A 64 MiB BO already needs at least an order-6 allocation, which fails under fragmentation and triggers a warn_alloc() splat on BO close: page allocation failure: order:7, mode:0x40cc0(GFP_KERNEL|__GFP_COMP) Call trace: ... warn_alloc+0x118/0x190 __alloc_pages_slowpath+0x4a8/0x520 ... __kmalloc_noprof+0x3ac/0x5d8 vc4_free_object+0x128/0x370 [vc4] drm_gem_object_handle_put_unlocked+0xb8/0x158 [drm] drm_gem_object_release_handle+0x74/0xe8 [drm] drm_gem_handle_delete+0x6c/0xa8 [drm] drm_gem_close_ioctl+0x34/0x50 [drm] The list doesn't need physically contiguous memory. Use kvmalloc_objs() so large lists can fall back to vmalloc(), avoiding the allocation failure. Fixes: c826a6e10644 ("drm/vc4: Add a BO cache.") Reviewed-by: Thadeu Lima de Souza Cascardo Link: https://patch.msgid.link/20260930190721.1897264-2-mcanal@igalia.com Signed-off-by: Maíra Canal --- drivers/gpu/drm/vc4/vc4_bo.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/vc4/vc4_bo.c b/drivers/gpu/drm/vc4/vc4_bo.c index ea1be891ac78..7b8b3364000f 100644 --- a/drivers/gpu/drm/vc4/vc4_bo.c +++ b/drivers/gpu/drm/vc4/vc4_bo.c @@ -204,7 +204,7 @@ static struct list_head *vc4_get_cache_list_for_size(struct drm_device *dev, struct list_head *new_list; uint32_t i; - new_list = kmalloc_objs(struct list_head, new_size); + new_list = kvmalloc_objs(struct list_head, new_size); if (!new_list) return NULL; @@ -224,7 +224,7 @@ static struct list_head *vc4_get_cache_list_for_size(struct drm_device *dev, for (i = vc4->bo_cache.size_list_size; i < new_size; i++) INIT_LIST_HEAD(&new_list[i]); - kfree(vc4->bo_cache.size_list); + kvfree(vc4->bo_cache.size_list); vc4->bo_cache.size_list = new_list; vc4->bo_cache.size_list_size = new_size; } @@ -1052,7 +1052,7 @@ static void vc4_bo_cache_destroy(struct drm_device *dev, void *unused) cancel_work_sync(&vc4->bo_cache.time_work); vc4_bo_cache_purge(dev); - kfree(vc4->bo_cache.size_list); + kvfree(vc4->bo_cache.size_list); for (i = 0; i < vc4->num_labels; i++) { if (vc4->bo_labels[i].num_allocated) {