Backtrace in media_pipeline_stop with bcm2835-unicam

[floe]

Describe the bug

I'm running a Raspberry Pi with HQ camera as timelapse webcam. Everything seems to be working fine, so this is probably relatively low priority, but I still wanted to mention that I'm getting the following backtrace in media_pipeline_stop for every picture taken with libcamera.

Steps to reproduce the behaviour

The following Python code triggers this issue when run repeatedly every 2 minutes via cronjob:

#!/usr/bin/python3

# based on https://github.com/raspberrypi/picamera2/blob/main/examples/opencv_mertens_merge.py

#import numpy as np
import time,os,cv2,shutil
from picamera2 import Picamera2
from libcamera import Transform
from datetime import datetime

RATIO = 3.0
RATIO2 = RATIO*RATIO

picam2 = Picamera2()
controls = {}

def expose(prefix,duration):
    controls["ExposureTime"] = int(duration)
    print(controls)
    picam2.set_controls(controls)
    picam2.start()
    data = picam2.capture_array()
    picam2.stop()
    means = cv2.mean(data)
    mean = (means[0]+means[1]+means[2])/3
    if mean < 15 or mean > 240:
        return 0
    cv2.imwrite(prefix+".jpg", data)
    return mean

# "main()"

prefix = datetime.now().strftime("%Y%m%d-%H%M%S")
path = "/var/ram/"+prefix
os.mkdir(path)
os.chdir(path)

# Run for a second to get a reasonable "middle" exposure level.
picam2.configure(picam2.create_preview_configuration())
picam2.start()
time.sleep(1)
metadata = picam2.capture_metadata()
picam2.stop()

# get the auto-calibrated values
exposure_normal = metadata["ExposureTime"]
gain = metadata["AnalogueGain"] * metadata["DigitalGain"]
wb = metadata["ColourGains"]

# create default configuration
controls = { "ExposureTime": exposure_normal, "AnalogueGain": gain, "AeEnable": False, "ColourGains": wb }
capture_config = picam2.create_still_configuration(main = {"size": (3840, 2160), "format": "RGB888"}) 
#transform=Transform(hflip=1,vflip=1)) #, controls=controls)
picam2.configure(capture_config)

# get 5 exposures
expose(prefix+"-vs", exposure_normal / RATIO2)
expose(prefix+"-sh", exposure_normal / RATIO )
expose(prefix+"-nm", exposure_normal         )
expose(prefix+"-lg", exposure_normal * RATIO )
expose(prefix+"-vl", exposure_normal * RATIO2)

Device (s)

Raspberry Pi Zero W / WH

System

Raspberry Pi reference 2022-09-22
Generated using pi-gen, https://github.com/RPi-Distro/pi-gen, 8a42abcd1dbd8c9c1fdfca4e0c3778255b2f9cc4, stage2

Mar 17 2023 10:52:42
Copyright (c) 2012 Broadcom
version 82f3750a65fadae9a38077e3c2e217ad158c8d54 (clean) (release) (start)

Linux XXXXXXX 6.1.19+ #1637 Tue Mar 14 11:01:56 GMT 2023 armv6l GNU/Linux

Logs

[244731.171175] ------------[ cut here ]------------
[244731.171210] WARNING: CPU: 0 PID: 900 at drivers/media/mc/mc-entity.c:873 media_pipeline_stop+0x28/0x34 [mc]
[244731.171417] Modules linked in: cmac algif_hash aes_arm aes_generic ecb algif_skcipher af_alg bnep imx477 hci_uart btbcm bluetooth brcmfmac ecdh_generic ecc libaes vc4 brcmutil sha256_generic libsha256 snd_soc_hdmi_codec 8021q garp stp llc drm_display_helper cec cfg80211 drm_dma_helper drm_kms_helper snd_soc_core bcm2835_unicam snd_compress v4l2_dv_timings snd_pcm_dmaengine syscopyarea v4l2_fwnode sysfillrect sysimgblt bcm2835_codec(C) i2c_mux_pinctrl fb_sys_fops i2c_mux raspberrypi_hwmon v4l2_async bcm2835_v4l2(C) bcm2835_isp(C) v4l2_mem2mem bcm2835_mmal_vchiq(C) rfkill videobuf2_vmalloc videobuf2_dma_contig videobuf2_memops videobuf2_v4l2 videobuf2_common snd_bcm2835(C) videodev snd_pcm snd_timer i2c_bcm2835 snd vc_sm_cma(C) mc uio_pdrv_genirq uio fixed drm fuse drm_panel_orientation_quirks backlight ip_tables x_tables ipv6
[244731.171829] CPU: 0 PID: 900 Comm: raspberry_fakeh Tainted: G WC 6.1.19+ #1637
[244731.171848] Hardware name: BCM2835
[244731.171865] unwind_backtrace from show_stack+0x18/0x1c
[244731.171904] show_stack from dump_stack_lvl+0x34/0x58
[244731.171934] dump_stack_lvl from __warn+0x7c/0xf8
[244731.171967] __warn from warn_slowpath_fmt+0x60/0xcc
[244731.172002] warn_slowpath_fmt from media_pipeline_stop+0x28/0x34 [mc]
[244731.172150] media_pipeline_stop [mc] from unicam_stop_streaming+0x88/0x168 [bcm2835_unicam]
[244731.172343] unicam_stop_streaming [bcm2835_unicam] from __vb2_queue_cancel+0x30/0x284 [videobuf2_common]
[244731.172554] __vb2_queue_cancel [videobuf2_common] from vb2_core_streamoff+0x20/0xb8 [videobuf2_common]
[244731.172739] vb2_core_streamoff [videobuf2_common] from __video_do_ioctl+0x224/0x458 [videodev]
[244731.173460] __video_do_ioctl [videodev] from video_usercopy+0x118/0x574 [videodev]
[244731.174268] video_usercopy [videodev] from sys_ioctl+0x10c/0x90c
[244731.174705] sys_ioctl from ret_fast_syscall+0x0/0x1c
[244731.174732] Exception stack(0xdc905fa8 to 0xdc905ff0)
[244731.174752] 5fa0: a4311ef0 a430d65c 0000000f 40045613 a4312f30 00000000
[244731.174770] 5fc0: a4311ef0 a430d65c a430d670 00000036 0238e568 00000000 b6e90134 0238e508
[244731.174783] 5fe0: a52b9d44 a4cc770c a5237940 b6d0dd4c
[244731.174795] ---[ end trace 0000000000000000 ]---

Additional context

No response

[6by9]

See #5409