Provided support information as requested. thank you

On Mon, 19 Oct 2026 at 05:40, Changwei Zou <[email protected]>
wrote:

> Thank you very much for reporting this issue.
> Could you please provide more information?
> Please boot into the Ubuntu kernel and run the following command in a
> terminal
> to collect debugging information and attach it to this report.
>
> $ sudo apport-collect 2171043
>
> ** Changed in: linux (Ubuntu)
>        Status: New => Incomplete
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/2171043
>
> Title:
>   ipu-bridge lists SONY471A twice (mainline + SAUCE): IPU7 probe fails
>   with -EEXIST, imx471 use-after-free oops, suspend hangs
>
> Status in linux package in Ubuntu:
>   Incomplete
>
> Bug description:
>   Release: Ubuntu 26.04 (resolute)
>   Kernel:  linux-image-7.0.0-38-generic 7.0.0-38.38 (also present in
> linux-oem-26.04 7.0.0-1015.15)
>   Machine: Lenovo ThinkPad X9-15 Gen 1 (21Q6001FZA), BIOS N4CET41W (1.17),
> Lunar Lake,
>            IPU7 8086:645d, Sony IMX471 sensor (ACPI HID SONY471A)
>
>   PROBLEM
>
>   In drivers/media/pci/intel/ipu-bridge.c in 7.0.0-38.38,
> ipu_supported_sensors[] contains
>   IPU_SENSOR_CONFIG("SONY471A", 1, 200000000) twice:
>
>     - line 107: from mainline v7.0. It is present in
> linux_7.0.0.orig.tar.gz.
>     - line 111: added again by the carried patch
>       "UBUNTU: SAUCE: media: ipu-bridge: Support imx471 sensor" (LP:
> #2107320).
>
>   ipu_bridge_connect_sensors() handles the second entry, finds the same
> ACPI device and tries
>   to register software nodes with the same names. intel-ipu7 then fails to
> probe on every boot:
>
>     sysfs: cannot create duplicate filename
> '/kernel/software_nodes/SONY471A-0'
>     kobject: kobject_add_internal failed for SONY471A-0 with -EEXIST, ...
>     intel-ipu7 0000:00:05.0: error -EEXIST: IPU bridge init failed
>     intel-ipu7 0000:00:05.0: probe with driver intel-ipu7 failed with
> error -17
>
>   The error path unregisters the bridge's software nodes, but the imx471
> sensor driver
>   (ubuntu/dkms/ipu6/imx471.ko) is probing against those nodes.
> imx471_check_hwcfg() then uses
>   freed fwnode memory. Every boot logs "refcount_t: addition on 0;
> use-after-free" warnings. On
>   some boots (3 of 5 here) it oopses inside the deferred-probe worker:
>
>     BUG: unable to handle page fault for address: 0000000a00000094
>     Workqueue: events_unbound deferred_probe_work_func
>     RIP: 0010:fwnode_graph_get_next_endpoint+0x42/0xc0
>      imx471_check_hwcfg+0x68/0x190 [imx471]
>      imx471_probe+0x31/0x4e0 [imx471]
>      i2c_device_probe ... deferred_probe_work_func
>
>   (One boot showed "BUG: kernel NULL pointer dereference, address:
>   0000000000000009" at the same RIP.)
>
>   IMPACT
>
>   - The webcam never works: the IPU7 device stays unbound.
>   - After the oops, the dead kworker leaves a probe in flight, so
> wait_for_device_probe() never
>     returns. dpm_prepare() and device_shutdown() both call it, so:
>     * lid-close suspend never completes. The internal panel stays black on
> lid open, external
>       displays get no signal, and a forced power-off is needed (attachment
> suspend-hang-journal.txt;
>       the journal ends at "PM: suspend entry (s2idle)" / "Filesystems
> sync").
>     * reboot/shutdown can hang at the very end.
>     To users this looks like a display/graphics resume bug, which makes it
> hard to diagnose.
>
>   STEPS TO REPRODUCE
>
>   1. Boot 7.0.0-38-generic on a machine with a SONY471A sensor (e.g.
> ThinkPad X9-15 Gen 1).
>   2. dmesg | grep -E "SONY471A-0|IPU bridge init|refcount_t|BUG:"
>      -> the duplicate-name error and -EEXIST appear every boot;
> use-after-free warnings or an oops follow.
>   3. If an oops occurred: close the lid. The machine never comes back from
> suspend.
>
>   FIX
>
>   Drop the duplicate entry (attached
> 0001-ipu-bridge-drop-duplicate-SONY471A-entry.patch); keep
>   TBE20A0, which mainline doesn't have. The SAUCE patch's SONY471A line
> has been redundant
>   since mainline added the entry.
>
>   TESTED
>
>   - I rebuilt ipu-bridge.ko from the linux_7.0.0-38.38 source package. The
> unmodified build has the
>     same srcversion as the shipped module (4DB31BE24A1FDC6F27DA3A5), so
> the source matches.
>   - With only the duplicate line removed:
>     "intel-ipu7 0000:00:05.0: Found supported sensor SONY471A:00",
> "Connected 1 cameras",
>     "imx471 i2c-SONY471A:00: imx471 probe successfully", "All sensor
> registration completed".
>     No refcount warnings and no oops across several boots. Lid-close
> suspend/resume works.
>     The camera works through libcamhal-ipu7x / icamerasrc / v4l2-relayd.
>   - linux-oem-26.04 7.0.0-1015.15: I didn't boot it, but the
> ipu_supported_sensors[] table in its
>     shipped ipu-bridge.ko (read from the relocations) has the same two
> consecutive SONY471A
>     entries, so it is affected too.
>
>   Note: the running system now uses the locally rebuilt ipu-bridge.ko
> (taint E). The attached
>   logs are from boots of the unmodified stock kernel.
>
>
>   # Last journal lines of two boots on 7.0.0-38-generic where the same
> oops occurred at boot.
>   # Lid close -> suspend never completes / never resumes; machine needed a
> forced power-off.
>
>   ## boot 9817a19537db4cc5a9cd69315c633da5
>   oops at boot: BUG: kernel NULL pointer dereference, address:
> 0000000000000009
>   2026-10-15T08:58:43+02:00 systemd-logind[1149]: Suspending...
>   2026-10-15T08:59:13+02:00 systemd[1]: Reached target sleep.target -
> Sleep.
>   2026-10-15T08:59:13+02:00 systemd-sleep[29292]: Successfully froze unit
> 'user.slice'.
>   2026-10-15T08:59:13+02:00 systemd-sleep[29292]: Performing sleep
> operation 'suspend'...
>   2026-10-15T08:59:13+02:00 kernel: PM: suspend entry (s2idle)
>   2026-10-15T08:59:13+02:00 kernel: Filesystems sync: 0.011 seconds
>
>   ## boot 8c4e64b1100643058a7f1a25f338741d
>   oops at boot: BUG: unable to handle page fault for address:
> 000001a400000084
>   2026-10-15T11:59:47+02:00 systemd-logind[1272]: Suspending...
>   2026-10-15T11:59:49+02:00 systemd[1]: Reached target sleep.target -
> Sleep.
>   2026-10-15T11:59:49+02:00 systemd-sleep[15196]: Successfully froze unit
> 'user.slice'.
>   2026-10-15T11:59:49+02:00 systemd-sleep[15196]: Performing sleep
> operation 'suspend'...
>   2026-10-15T11:59:49+02:00 kernel: PM: suspend entry (s2idle)
>   2026-10-15T11:59:49+02:00 kernel: Filesystems sync: 0.010 seconds
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2171043/+subscriptions
>
>

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https://bugs.launchpad.net/bugs/2171043

Title:
  ipu-bridge lists SONY471A twice (mainline + SAUCE): IPU7 probe fails
  with -EEXIST, imx471 use-after-free oops, suspend hangs

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2171043/+subscriptions


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