Description of problem:
Running ffmpeg to use v4l2 capture device.

The v4l2 device is a KWorld 110/115 (card 90) using the saa7133/7134 device, using the saa7134 kernel module.

VLC and Qt V4l2 test utility seem to work fine with the same v4l2 saa7134 capture device, no apparent errors.

command line: "ffmpeg -f v4l2 -standard NTSC -video_size 640x480 -channel 1 -i /dev/video1"

ffmpeg continously reports  "libv4l2: error dequeuing buf: Resource temporarily unavailable". It does complete job, but memory does fill. However, it appears to trash the PCI bus at some point, ultimately resetting other PCI cards and the atl1c ethernet controller.

Up to date Fedora 19, tried many different kernel versions, using ffmpeg from the repositories. Motherboard ASRock Extreme 3.0 Rev 2.0. Has been very stable until now.

dmesg is clean, showing only shows the other drivers for devices on the pci bus complaining when they cannot access their hardware. abrt shows kernel BUG at drivers/media/v4l2-core/videobuf-dma-sg.c:140

Additional Errors seen:
[ 3984.642752] vbuf: dqbuf: state is done
[ 3984.642763] vbuf: dqbuf: next_buffer error: -11
[ 3984.647265] vbuf: qbuf: requesting next field


ffmpeg version 1.2.6 Copyright (c) 2000-2014 the FFmpeg developers
  built on Mar  5 2014 08:21:01 with gcc 4.8.2 (GCC) 20131212 (Red Hat 4.8.2-7)
  configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man --arch=x86_64 --optflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic' --enable-bzlib --disable-crystalhd --enable-frei0r --enable-gnutls --enable-libass --enable-libcelt --enable-libdc1394 --disable-indev=jack --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-openal --enable-libopencv --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libv4l2 --enable-libvpx --enable-libx264 --enable-libxvid --enable-x11grab --enable-avfilter --enable-avresample --enable-postproc --enable-pthreads --disable-static --enable-shared --enable-gpl --disable-debug --disable-stripping --shlibdir=/usr/lib64 --enable-runtime-cpudetect
  libavutil      52. 18.100 / 52. 18.100
  libavcodec     54. 92.100 / 54. 92.100
  libavformat    54. 63.104 / 54. 63.104
  libavdevice    54.  3.103 / 54.  3.103
  libavfilter     3. 42.103 /  3. 42.103
  libswscale      2.  2.100 /  2.  2.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100



Additional info:
reporter:       libreport-2.2.1
kernel BUG at drivers/media/v4l2-core/videobuf-dma-sg.c:140!
invalid opcode: 0000 [#1] SMP 
Modules linked in: fuse ip6t_rpfilter ip6t_REJECT xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw w83627ehf hwmon_vid saa7134_alsa nxt200x saa7134_dvb videobuf_dvb dvb_core tuner_simple tuner_types tuner kvm_amd kvm crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel joydev microcode saa7134 snd_hda_codec_realtek snd_hda_codec_generic tveeprom snd_hda_codec_hdmi videobuf_dma_sg serio_raw edac_core videobuf_core fam15h_power rc_core snd_hda_intel v4l2_common snd_hda_codec snd_hwdep edac_mce_amd k10temp videodev snd_seq snd_seq_device media snd_pcm i2c_piix4 atl1c snd_timer snd soundcore shpchp wmi acpi_cpufreq uinput radeon firewire_ohci firewire_core i2c_algo_bit sata_sil24 drm_kms_helper crc_itu_t ttm drm i2c_core
CPU: 2 PID: 2375 Comm: ffmpeg Not tainted 3.14.7-100.fc19.x86_64 #1
Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./870 Extreme3 R2.0, BIOS P1.80B 04/11/2013
task: ffff8800b7bf8000 ti: ffff8800b9bde000 task.ti: ffff8800b9bde000
RIP: 0010:[<ffffffffa032e870>]  [<ffffffffa032e870>] videobuf_to_dma+0x20/0x40 [videobuf_dma_sg]
RSP: 0018:ffff8800b9bdfd70  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88021a338e00 RCX: 0000000000000001
RDX: ffff880220f4c210 RSI: ffff88021a338e00 RDI: ffff88021a338e00
RBP: ffff8800b9bdfd90 R08: 0000000000000000 R09: 0000000000000000
R10: ffff88021ca8f1a0 R11: ffff880220f4c210 R12: 0000000000000000
R13: ffff88021d468b88 R14: ffff880220f4c200 R15: ffff880221b262a0
FS:  00007f2b4e7fa7c0(0000) GS:ffff88022ec80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000003c232bd6b0 CR3: 0000000001c0c000 CR4: 00000000000407e0
Stack:
 ffffffffa038ba9c ffff88021d468000 0000000000000000 ffff8801fd028c80
 ffff8800b9bdfe00 ffffffffa0392e43 ffff8800c8a64400 00000000cf124ca6
 0000000010942480 0000000000000000 ffff880220f4c210 0000000800000001
Call Trace:
 [<ffffffffa038ba9c>] ? saa7134_dma_free+0x1c/0x70 [saa7134]
 [<ffffffffa0392e43>] video_release+0x83/0x300 [saa7134]
 [<ffffffffa029d498>] v4l2_release+0x38/0x80 [videodev]
 [<ffffffff811eb84c>] __fput+0xdc/0x230
 [<ffffffff811eb9ee>] ____fput+0xe/0x10
 [<ffffffff810ab094>] task_work_run+0xc4/0xe0
 [<ffffffff8108c774>] do_exit+0x2c4/0xa30
 [<ffffffff811a92a7>] ? do_munmap+0x297/0x3b0
 [<ffffffff8108cf5f>] do_group_exit+0x3f/0xa0
 [<ffffffff8108cfd4>] SyS_exit_group+0x14/0x20
 [<ffffffff81700869>] system_call_fastpath+0x16/0x1b
Code: 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 48 8b 87 a8 00 00 00 48 85 c0 74 0f 8b 30 81 fe 14 07 89 17 75 07 48 83 c0 08 c3 <0f> 0b 55 ba 14 07 89 17 48 c7 c7 68 01 33 a0 31 c0 48 89 e5 e8 
RIP  [<ffffffffa032e870>] videobuf_to_dma+0x20/0x40 [videobuf_dma_sg]
 RSP <ffff8800b9bdfd70>