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. Regards, Hans