In preparation for using bridge->next_bridge, we need to ensure that it
will never contain anything but NULL or a valid bridge pointer. Current
code stores an ERR_PTR when imx8qxp_pxl2dpi_find_next_bridge() errors
out. Instead of fixing that after the facts in the caller, change the
function to internally set the next_pointer and just return an int error
value.
No functional changes.
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://patch.msgid.link/20251216-drm-bridge-alloc-getput-drm_of_find_bridge-v3-15-b5165fab8058@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Many bridge drivers store a next_bridge pointer in their private data and
use it for attach and sometimes other purposes. This is going to be risky
when bridge hot-unplug is used.
Considering this example scenario:
1. pipeline: encoder --> bridge A --> bridge B --> bridge C
2. encoder takes a reference to bridge B
3. bridge B takes a next_bridge reference to bridge C
4. encoder calls (bridge B)->b_foo(), which in turns references
next_bridge, e.g.:
b_foo() {
bar(b->next_bridge);
}
If bridges B and C are removed, bridge C can be freed but B is still
allocated because the encoder holds a reference to B. So when step 4
happens, 'b->next-bridge' would be a use-after-free.
Calling drm_bridge_put() in the B bridge .remove function does not solve
the problem as it leaves a (potentially long) risk window between B removal
and the final deallocation of B. A safe moment to put the B reference is in
__drm_bridge_free(), when the last reference has been put. This can be done
by drivers in the .destroy func. However to avoid the need for so many
drivers to implement a .destroy func, just offer a next_bridge pointer to
all bridges that is automatically put it in __drm_bridge_free(), exactly
when the .destroy func is called.
Suggested-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/all/20251201-thick-jasmine-oarfish-1eceb0@houat/
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://patch.msgid.link/20251216-drm-bridge-alloc-getput-drm_of_find_bridge-v3-6-b5165fab8058@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
While LT9611UXC is a DSI-to-HDMI bridge, it implements all HDMI-related
functions internally, in the firmware, thus it doesn't make sense to
implement DRM_BRIDGE_OP_HDMI. However it is possible to implement
DRM_BRIDGE_OP_HDMI_AUDIO, streamlining HDMI audio plumbing (which
includes plugged notifications and ELD handling).
Implement corresponding callbacks and trigger EDID read /
drm_connector_hdmi_audio_plugged_notify() from the hpd_notify callback.
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patch.msgid.link/20250803-lt9611uxc-hdmi-v1-2-cb9ce1793acf@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Acquire and release the GEM object's reservation lock around calls
to the object's purge operation. The tests use
drm_gem_shmem_purge_locked(), which led to errors such as show below.
[ 58.709128] WARNING: CPU: 1 PID: 1354 at drivers/gpu/drm/drm_gem_shmem_helper.c:515 drm_gem_shmem_purge_locked+0x51c/0x740
Only export the new helper drm_gem_shmem_purge() for Kunit tests.
This is not an interface for regular drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 954907f714 ("drm/shmem-helper: Refactor locked/unlocked functions")
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.16+
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patch.msgid.link/20251212160317.287409-6-tzimmermann@suse.de
Acquire and release the GEM object's reservation lock around calls
to the object's madvide operation. The tests use
drm_gem_shmem_madvise_locked(), which led to errors such as show below.
[ 58.339389] WARNING: CPU: 1 PID: 1352 at drivers/gpu/drm/drm_gem_shmem_helper.c:499 drm_gem_shmem_madvise_locked+0xde/0x140
Only export the new helper drm_gem_shmem_madvise() for Kunit tests.
This is not an interface for regular drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 954907f714 ("drm/shmem-helper: Refactor locked/unlocked functions")
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.16+
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patch.msgid.link/20251212160317.287409-5-tzimmermann@suse.de
Acquire and release the GEM object's reservation lock around vmap and
vunmap operations. The tests use vmap_locked, which led to errors such
as show below.
[ 122.292030] WARNING: CPU: 3 PID: 1413 at drivers/gpu/drm/drm_gem_shmem_helper.c:390 drm_gem_shmem_vmap_locked+0x3a3/0x6f0
[ 122.468066] WARNING: CPU: 3 PID: 1413 at drivers/gpu/drm/drm_gem_shmem_helper.c:293 drm_gem_shmem_pin_locked+0x1fe/0x350
[ 122.563504] WARNING: CPU: 3 PID: 1413 at drivers/gpu/drm/drm_gem_shmem_helper.c:234 drm_gem_shmem_get_pages_locked+0x23c/0x370
[ 122.662248] WARNING: CPU: 2 PID: 1413 at drivers/gpu/drm/drm_gem_shmem_helper.c:452 drm_gem_shmem_vunmap_locked+0x101/0x330
Only export the new vmap/vunmap helpers for Kunit tests. These are
not interfaces for regular drivers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 954907f714 ("drm/shmem-helper: Refactor locked/unlocked functions")
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.16+
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patch.msgid.link/20251212160317.287409-4-tzimmermann@suse.de
Commit 33729a5fc0 ("iommu/io-pgtable-arm: Remove split on unmap
behavior") did away with the treatment of partial unmaps of huge IOPTEs.
In the case of Panthor, that means an attempt to run a VM_BIND unmap
operation on a memory region whose start address and size aren't 2MiB
aligned, in the event it intersects with a huge page, would lead to ARM
IOMMU management code to fail and a warning being raised.
Presently, and for lack of a better alternative, it's best to have
Panthor handle partial unmaps at the driver level, by unmapping entire
huge pages and remapping the difference between them and the requested
unmap region.
This could change in the future when the VM_BIND uAPI is expanded to
enforce huge page alignment and map/unmap operational constraints that
render this code unnecessary.
When a partial unmap for a huge PTE is attempted, we also need to expand
the locked region to encompass whole huge pages.
Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20251217213252.677020-2-adrian.larumbe@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Ensure all related groups are evicted and suspended before VM
destruction takes place.
This fixes an issue where panthor_vm_destroy() destroys and unmaps the
heap context while there are still on slot groups using this.
The FW will do a write out to the heap context when a CSG (group) is
suspended, so a premature unmap of the heap context will cause a
GPU page fault.
This page fault is quite harmless, and do not affect the continued
operation of the GPU.
Fixes: 647810ec24 ("drm/panthor: Add the MMU/VM logical block")
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Ketil Johnsen <ketil.johnsen@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20251219093546.1227697-1-ketil.johnsen@arm.com
Co-developed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Newer firmware versions prefer temporal sharing only mode. In this mode,
the driver no longer needs to manage AIE array column allocation. Instead,
a new field, num_unused_col, is added to the hardware context creation
request to specify how many columns will not be used by this hardware
context.
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patch.msgid.link/20251217191150.2145937-1-lizhi.hou@amd.com
Since we can only inspect dmabuf by iterating over process FDs or the
dmabuf_list, we need to add our own tracepoints to track its status in
real time in production.
For example:
binder:3016_1-3102 [006] ...1. 255.126521: dma_buf_export: exp_name=qcom,system size=12685312 ino=2738
binder:3016_1-3102 [006] ...1. 255.126528: dma_buf_fd: exp_name=qcom,system size=12685312 ino=2738 fd=8
binder:3016_1-3102 [006] ...1. 255.126642: dma_buf_mmap_internal: exp_name=qcom,system size=28672 ino=2739
kworker/6:1-86 [006] ...1. 255.127194: dma_buf_put: exp_name=qcom,system size=12685312 ino=2738
RenderThread-9293 [006] ...1. 316.618179: dma_buf_get: exp_name=qcom,system size=12771328 ino=2762 fd=176
RenderThread-9293 [006] ...1. 316.618195: dma_buf_dynamic_attach: exp_name=qcom,system size=12771328 ino=2762 attachment:ffffff880a18dd00 is_dynamic=0 dev_name=kgsl-3d0
RenderThread-9293 [006] ...1. 318.878220: dma_buf_detach: exp_name=qcom,system size=12771328 ino=2762 attachment:ffffff880a18dd00 is_dynamic=0 dev_name=kgsl-3d0
Signed-off-by: Xiang Gao <gaoxiang17@xiaomi.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20251218062853.819744-1-gxxa03070307@gmail.com
Signed-off-by: Christian König <christian.koenig@amd.com>
amdxdna_flush() was introduced to ensure that the device does not access
a process address space after it has been freed. However, this is no
longer necessary because the driver now increments the mm reference count
when a command is submitted and decrements it only after the command has
completed. This guarantees that the process address space remains valid
for the entire duration of command execution. Remove amdxdna_flush to
simplify the teardown path.
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patch.msgid.link/20251216031311.2033399-1-lizhi.hou@amd.com
Luca Ceresoli
Andy Yan
Dmitry Baryshkov
Jani Nikula
René Rebe
Thomas Zimmermann
Biju Das
Francesco Valla
Adrián Larumbe
Ketil Johnsen
Lizhi Hou
gaoxiang17
Loïc Molinari
Dan Carpenter
Tvrtko Ursulin
Boris Brezillon
Chia-I Wu
Christian König
Karunika Choo
Renjun Wang