On 4/3/20 7:45 AM, Sowjanya Komatineni wrote: > > On 3/30/20 9:16 AM, Sowjanya Komatineni wrote: >> >> On 3/30/20 4:02 AM, Hans Verkuil wrote: >>> External email: Use caution opening links or attachments >>> >>> >>> On 3/30/20 12:04 PM, Hans Verkuil wrote: >>>> Hi Sowjanya, >>>> >>>> On 3/23/20 6:52 PM, Sowjanya Komatineni wrote: >>>>> This series adds Tegra210 VI and CSI driver for built-in test pattern >>>>> generator (TPG) capture. >>>>> >>>>> Tegra210 supports max 6 channels on VI and 6 ports on CSI where each >>>>> CSI port is one-to-one mapped to VI channel for video capture. >>>>> >>>>> This series has TPG support only where it creates hard media links >>>>> between CSI subdevice and VI video device without device graphs. >>>>> >>>>> v4l2-compliance results are available below the patch diff. >>>>> >>>>> [v5]: Includes, >>>>> - v4 feedback >>>>> - fix for venc powergate mc reset order. >>>>> - fix to have unbind and bind work during v4l2-ctl sleep and >>>>> streaming. >>>> Unfortunately, I still crash on this. >>>> >>>> I do the following: >>>> >>>> Run: v4l2-ctl --stream-mmap >>>> >>>> Then, from another shell as root: >>>> >>>> cd /sys/devices/platform/50000000.host1x/tegra-video/driver >>>> echo -n tegra-video > unbind >>>> >>>> I get this crash: >>>> >>>> [ 315.691971] Unable to handle kernel NULL pointer dereference at >>>> virtual address 00000000000000b0 >>>> [ 315.700749] Mem abort info: >>>> [ 315.703536] ESR = 0x96000004 >>>> [ 315.706587] EC = 0x25: DABT (current EL), IL = 32 bits >>>> [ 315.711886] SET = 0, FnV = 0 >>>> [ 315.714933] EA = 0, S1PTW = 0 >>>> [ 315.718064] Data abort info: >>>> [ 315.720936] ISV = 0, ISS = 0x00000004 >>>> [ 315.724763] CM = 0, WnR = 0 >>>> [ 315.727726] user pgtable: 4k pages, 48-bit VAs, >>>> pgdp=0000000178ee8000 >>>> [ 315.734152] [00000000000000b0] pgd=0000000000000000 >>>> [ 315.739024] Internal error: Oops: 96000004 [#1] PREEMPT SMP >>>> [ 315.744584] Modules linked in: r8152 nouveau lp855x_bl tegra_drm ttm >>>> [ 315.750942] CPU: 3 PID: 2206 Comm: bash Tainted: G W >>>> 5.6.0-rc1-arm64 #118 >>>> [ 315.759017] Hardware name: NVIDIA Jetson TX1 Developer Kit (DT) >>>> [ 315.764927] pstate: 20000085 (nzCv daIf -PAN -UAO) >>>> [ 315.769718] pc : _raw_write_lock_irqsave+0xb0/0x2b8 >>>> [ 315.774590] lr : ida_free+0x48/0x158 >>>> [ 315.778155] sp : ffff800011d8bba0 >>>> [ 315.781462] x29: ffff800011d8bba0 x28: ffff0000f4095400 >>>> [ 315.786766] x27: 0000000000000000 x26: 0000000000000000 >>>> [ 315.792070] x25: 0000000000000000 x24: 0000000000000000 >>>> [ 315.797372] x23: ffff0000f21ad400 x22: ffff0000f5c93000 >>>> [ 315.802674] x21: ffff0000f4095400 x20: ffff0000f86b5540 >>>> [ 315.807975] x19: 0000000000000000 x18: 0000000000000000 >>>> [ 315.813276] x17: 0000000000000001 x16: 0000000000000019 >>>> [ 315.818578] x15: 000000148ccdabe2 x14: 0000000000000136 >>>> [ 315.823879] x13: 0000000000000001 x12: 00000000000003f8 >>>> [ 315.829180] x11: 0000000000000000 x10: 0000000000000000 >>>> [ 315.834482] x9 : ffff0000ff899990 x8 : ffff0000ff899000 >>>> [ 315.839784] x7 : 0000000040000000 x6 : 0000000000210d00 >>>> [ 315.845085] x5 : 0000000000000001 x4 : 0000000000000000 >>>> [ 315.850386] x3 : 00000000000000b0 x2 : 0000000000000001 >>>> [ 315.855687] x1 : 0000000000000000 x0 : 0000000000000001 >>>> [ 315.860988] Call trace: >>>> [ 315.863432] _raw_write_lock_irqsave+0xb0/0x2b8 >>>> [ 315.867956] ida_free+0x48/0x158 >>>> [ 315.871184] __media_device_unregister_entity+0x28/0xf0 >>>> [ 315.876402] media_device_unregister+0x6c/0x148 >>>> [ 315.880927] host1x_video_remove+0x20/0x48 >>>> [ 315.885021] host1x_device_remove+0x1c/0x30 >>>> [ 315.889198] device_release_driver_internal+0xf4/0x1c0 >>>> [ 315.894325] device_driver_detach+0x14/0x20 >>>> [ 315.898503] unbind_store+0xd4/0xf8 >>>> [ 315.901986] drv_attr_store+0x20/0x30 >>>> [ 315.905645] sysfs_kf_write+0x40/0x50 >>>> [ 315.909301] kernfs_fop_write+0xf8/0x210 >>>> [ 315.913219] __vfs_write+0x18/0x40 >>>> [ 315.916616] vfs_write+0xdc/0x1c8 >>>> [ 315.919926] ksys_write+0x68/0xf0 >>>> [ 315.923235] __arm64_sys_write+0x18/0x20 >>>> [ 315.927154] el0_svc_common.constprop.0+0x68/0x160 >>>> [ 315.931936] do_el0_svc+0x20/0x80 >>>> [ 315.935246] el0_sync_handler+0x10c/0x180 >>>> [ 315.939246] el0_sync+0x140/0x180 >>>> [ 315.942560] Code: 8803fc02 35ffffa3 17fffda6 f9800071 (885ffc60) >>>> [ 315.948644] ---[ end trace e42b943f3c1af06c ]--- >>>> >>>> The following diff fixes this: >>>> >>>> ------------------ cut here ------------------ >>>> diff --git a/drivers/staging/media/tegra/tegra-vi.c >>>> b/drivers/staging/media/tegra/tegra-vi.c >>>> index 9714152aa6a7..53cf37af9602 100644 >>>> --- a/drivers/staging/media/tegra/tegra-vi.c >>>> +++ b/drivers/staging/media/tegra/tegra-vi.c >>>> @@ -583,7 +583,7 @@ static int tegra_channel_init(struct >>>> tegra_vi_channel *chan) >>>> /* initialize the video_device */ >>>> chan->video->fops = &tegra_channel_fops; >>>> chan->video->v4l2_dev = &vid->v4l2_dev; >>>> - chan->video->release = video_device_release_empty; >>>> + chan->video->release = video_device_release; >>>> chan->video->queue = &chan->queue; >>>> snprintf(chan->video->name, sizeof(chan->video->name), >>>> "%s-%s-%u", >>>> dev_name(vi->dev), "output", chan->portno); >>>> @@ -647,6 +647,7 @@ static int tegra_channel_init(struct >>>> tegra_vi_channel *chan) >>>> media_entity_cleanup(&chan->video->entity); >>>> release_vdev: >>>> video_device_release(chan->video); >>>> + chan->video = NULL; >>>> return ret; >>>> } >>>> >>>> @@ -707,7 +708,6 @@ static void tegra_vi_channels_cleanup(struct >>>> tegra_vi *vi) >>>> mutex_lock(&chan->video_lock); >>>> vb2_queue_release(&chan->queue); >>>> mutex_unlock(&chan->video_lock); >>>> - video_device_release(chan->video); >>>> } >>>> >>>> if (chan->frame_start_sp) >>>> ------------------ cut here ------------------ >>> Note: Sakari suggested to embed struct video_device into struct >>> tegra_vi_channel. >>> In that case chan->video->release should remain >>> video_device_release_empty and >>> all video_device_alloc()/release() calls would have to be dropped. >> >> Thanks Hans. Tried several unbind/unbind not sure why it did not repro >> during my testing. >> >> video device is also part of tegra_vi_channel. So, v6 will remove >> video_device_alloc and use video_device_release_empty like I had in v3. >> >> This should help fix crash during unbind. >> >>> >>> Regards, >>> >>> Hans > > With video device being part of the channel structure, it gets allocated > along with vi channel allocation during host1x vi client init and is > removed during channel free which happens during host1x vi client exit. > > Wit this during driver unbind with video node kept opened with v4l2-ctl > sleep, it crashes during media_device_unregister_entity. > > Using, separate video device allocation and freeing allocation during > video device release callback, driver unbind works as by the time of > entity unregister its it still available. > > So, will keep allocating video device separately with video_device_alloc > and will use video_device_release call back in v6. > Sounds good. Add a comment before video_device_alloc() explaining why it is used instead of embedding it in the vi channel data structure. Regards, Hans
