Hi Laurentiu, Thanks for the patch. On Tue, Dec 17, 2024 at 08:51:50AM +0200, Laurentiu Palcu wrote: > The following kernel oops is thrown when trying to remove the max96712 > module: > > Unable to handle kernel paging request at virtual address 00007375746174db > Mem abort info: > ESR = 0x0000000096000004 > EC = 0x25: DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > FSC = 0x04: level 0 translation fault > Data abort info: > ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 > CM = 0, WnR = 0, TnD = 0, TagAccess = 0 > GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 > user pgtable: 4k pages, 48-bit VAs, pgdp=000000010af89000 > [00007375746174db] pgd=0000000000000000, p4d=0000000000000000 > Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP > Modules linked in: crct10dif_ce polyval_ce mxc_jpeg_encdec flexcan > snd_soc_fsl_sai snd_soc_fsl_asoc_card snd_soc_fsl_micfil dwc_mipi_csi2 > imx_csi_formatter polyval_generic v4l2_jpeg imx_pcm_dma can_dev > snd_soc_imx_audmux snd_soc_wm8962 snd_soc_imx_card snd_soc_fsl_utils > max96712(C-) rpmsg_ctrl rpmsg_char pwm_fan fuse > [last unloaded: imx8_isi] > CPU: 0 UID: 0 PID: 754 Comm: rmmod > Tainted: G C 6.12.0-rc6-06364-g327fec852c31 #17 > Tainted: [C]=CRAP > Hardware name: NXP i.MX95 19X19 board (DT) > pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : led_put+0x1c/0x40 > lr : v4l2_subdev_put_privacy_led+0x48/0x58 > sp : ffff80008699bbb0 > x29: ffff80008699bbb0 x28: ffff00008ac233c0 x27: 0000000000000000 > x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 > x23: ffff000080cf1170 x22: ffff00008b53bd00 x21: ffff8000822ad1c8 > x20: ffff000080ff5c00 x19: ffff00008b53be40 x18: 0000000000000000 > x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 > x14: 0000000000000004 x13: ffff0000800f8010 x12: 0000000000000000 > x11: ffff000082acf5c0 x10: ffff000082acf478 x9 : ffff0000800f8010 > x8 : 0101010101010101 x7 : 7f7f7f7f7f7f7f7f x6 : fefefeff6364626d > x5 : 8080808000000000 x4 : 0000000000000020 x3 : 00000000553a3dc1 > x2 : ffff00008ac233c0 x1 : ffff00008ac233c0 x0 : ff00737574617473 > Call trace: > led_put+0x1c/0x40 > v4l2_subdev_put_privacy_led+0x48/0x58 > v4l2_async_unregister_subdev+0x2c/0x1a4 > max96712_remove+0x1c/0x38 [max96712] > i2c_device_remove+0x2c/0x9c > device_remove+0x4c/0x80 > device_release_driver_internal+0x1cc/0x228 > driver_detach+0x4c/0x98 > bus_remove_driver+0x6c/0xbc > driver_unregister+0x30/0x60 > i2c_del_driver+0x54/0x64 > max96712_i2c_driver_exit+0x18/0x1d0 [max96712] > __arm64_sys_delete_module+0x1a4/0x290 > invoke_syscall+0x48/0x10c > el0_svc_common.constprop.0+0xc0/0xe0 > do_el0_svc+0x1c/0x28 > el0_svc+0x34/0xd8 > el0t_64_sync_handler+0x120/0x12c > el0t_64_sync+0x190/0x194 > Code: f9000bf3 aa0003f3 f9402800 f9402000 (f9403400) > ---[ end trace 0000000000000000 ]--- > > This happens because in v4l2_i2c_subdev_init(), the i2c_set_cliendata() > is called again and the data is overwritten to point to sd, instead of > priv. So, in remove(), the wrong pointer is passed to > v4l2_async_unregister_subdev(), leading to a crash. > > Fixes: 5814f32fef13 ("media: staging: max96712: Add basic support for MAX96712 GMSL2 deserializer") > Signed-off-by: Laurentiu Palcu <laurentiu.palcu@xxxxxxxxxxx> I believe Cc: stable is needed here, too, I'll add it. max96712 has been around for quite some time... > --- > Changes in v2: > * removed call to i2c_set_clientdata() in probe; > * cleaned up the trace in commit message as the tmux status line string > sneaked into it; > > Thanks, > Laurentiu > > drivers/staging/media/max96712/max96712.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/staging/media/max96712/max96712.c b/drivers/staging/media/max96712/max96712.c > index ede02e8c891cb..0751b2e048958 100644 > --- a/drivers/staging/media/max96712/max96712.c > +++ b/drivers/staging/media/max96712/max96712.c > @@ -418,7 +418,6 @@ static int max96712_probe(struct i2c_client *client) > priv->info = of_device_get_match_data(&client->dev); > > priv->client = client; > - i2c_set_clientdata(client, priv); > > priv->regmap = devm_regmap_init_i2c(client, &max96712_i2c_regmap); > if (IS_ERR(priv->regmap)) > @@ -448,7 +447,8 @@ static int max96712_probe(struct i2c_client *client) > > static void max96712_remove(struct i2c_client *client) > { > - struct max96712_priv *priv = i2c_get_clientdata(client); > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct max96712_priv *priv = container_of(sd, struct max96712_priv, sd); > > v4l2_async_unregister_subdev(&priv->sd); > -- Regards, Sakari Ailus