Hi Guennadi/Laurent, On Wed, May 2, 2012 at 4:20 AM, Guennadi Liakhovetski <g.liakhovetski@xxxxxx> wrote: > Hi Alex > > On Tue, 1 May 2012, Alex Gershgorin wrote: > >> Hi everyone, >> >> I use user-space utility from http://git.linuxtv.org/v4l-utils.git/blob/HEAD:/contrib/test/capture-example.c >> I made two small changes in this application and this is running on i.MX35 SoC >> >> fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB565; >> fmt.fmt.pix.field = V4L2_FIELD_ANY; >> >> When MMAP method is used everything works fine, problem occurs when using USERPTR method >> this can see bellow : >> >> ./capture-example -u -f -d /dev/video0 >> mx3-camera mx3-camera.0: MX3 Camera driver attached to camera 0 >> Failed acquiring VMA for vaddr 0x76cd9008 >> VIDIOC_QBUF error 22, Invalid arg > > It doesn't surprise me, that this doesn't work. capture-example allocates > absolutely normal user-space buffers, when called with USERPTR, and those > buffers are very likely discontiguous. Whereas mx3-camera needs physically > contiguous buffers, so, this can only fail. This means, you either have to > use MMAP or you need to allocate USERPTR buffers in a special way to > guarantee their contiguity. > Even I am facing a similar issue when ported to VB2 for USERPTR. How do we ensure the buffers not discontiguous. Would cmem assure it? Thx, --Prabhakar Lad >> Unable to handle kernel NULL pointer dereference at virtual address 00000000 > > This, however, is bad and is a bug in the driver. The capture-example > should just fail nicely with no trouble. I'll add it to my TODO and will > try to find some time to debug and fix this, however, I'd be more than > happy if someone else would beat me on this ;-) > > Thanks > Guennadi > >> pgd = 80004000 >> [00000000] *pgd=00000000 >> Internal error: Oops: 817 [#1] ARM >> CPU: 0 Not tainted (3.4.0-rc5+ #2283 >> PC is at mx3_videobuf_release+0x9c/0x10c >> LR is at mx3_videobuf_release+0x20/0x10c >> pc : [<802cd92c>] lr : [<802cd8b0>] psr: 00000093 >> sp : 86db3e00 ip : 86db3e00 fp : 86db3e2c >> r10: 86ff6b20 r9 : 86817200 r8 : 00000000 >> r7 : 86ff568c r6 : 00000000 r5 : 8801a000 r4 : 86da3000 >> r3 : 60000013 r2 : 86da3264 r1 : 00000000 r0 : 00000000 >> Flags: nzcv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user >> Control: 00c5387d Table: 86dcc008 DAC: 00000015 >> Process capture-example (pid: 52, stack limit = 0x86db2268) >> Stack: (0x86db3e00 to 0x86db4000) >> 3e00: 00000000 60000013 00000000 86ff568c 00000000 00000002 86ff56ac 00000000 >> 3e20: 86db3e64 86db3e30 802c8978 802cd89c 00000000 80099414 86db3e84 86ff568c >> 3e40: 86dc9a80 8801a03c 80491828 00000000 86817200 86ff6b20 86db3e7c 86db3e68 >> 3e60: 802c9a1c 802c8930 802ce048 86ff5600 86db3e9c 86db3e80 802cca14 802c9a00 >> 3e80: 86ff5800 86dc9a80 00000008 86dc9a88 86db3eb4 86db3ea0 802b936c 802cc9d0 >> 3ea0: 86dc9a80 86ff6b20 86db3ef4 86db3eb8 80082f00 802b932c 00000000 00000000 >> 3ec0: 00000000 86d35010 86d7f000 86dc9a80 00000000 86d59000 86d90120 0000000c >> 3ee0: 86db2000 00000000 86db3f14 86db3ef8 8007ff58 80082df0 00000000 86d59000 >> 3f00: 00000000 00000001 86db3f3c 86db3f18 8001c72c 8007fee4 86d59000 86d82000 >> 3f20: 00000100 76ef1770 000000f8 8000e564 86db3f4c 86db3f40 8001c7a8 8001c6b4 >> 3f40: 86db3f7c 86db3f50 8001dab4 8001c78c 7eb002b8 00000001 00000004 00000000 >> 3f60: 86db3fa4 86db3f70 800824fc 000000f8 86db3f94 86db3f80 8001dfc0 8001d8c4 >> 3f80: 0000ffff 000a3d78 86db3fa4 86db3f98 8001e004 8001df4c 00000000 86db3fa8 >> 3fa0: 8000e3e0 8001dff8 000a3d78 76ef1770 00000001 000a3d64 00000008 00000001 >> 3fc0: 000a3d78 76ef1770 76ef1770 000000f8 76e1d248 00000000 00009ecc 7eb02954 >> 3fe0: 76f2e000 7eb02908 76de14dc 76e4f3d4 60000010 00000001 00000000 00000000 >> Backtrace: >> [<802cd890>] (mx3_videobuf_release+0x0/0x10c) from [<802c8978>] (__vb2_queue_free+0x54/0x15c) >> r8:00000000 r7:86ff56ac r6:00000002 r5:00000000 r4:86ff568c >> [<802c8924>] (__vb2_queue_free+0x0/0x15c) from [<802c9a1c>] (vb2_queue_release+0x28/0x2c) >> [<802c99f4>] (vb2_queue_release+0x0/0x2c) from [<802cca14>] (soc_camera_close+0x50/0xac) >> r4:86ff5600 r3:802ce048 >> [<802cc9c4>] (soc_camera_close+0x0/0xac) from [<802b936c>] (v4l2_release+0x4c/0x6c) >> r7:86dc9a88 r6:00000008 r5:86dc9a80 r4:86ff5800 >> [<802b9320>] (v4l2_release+0x0/0x6c) from [<80082f00>] (fput+0x11c/0x204) >> r5:86ff6b20 r4:86dc9a80 >> [<80082de4>] (fput+0x0/0x204) from [<8007ff58>] (filp_close+0x80/0x8c) >> [<8007fed8>] (filp_close+0x0/0x8c) from [<8001c72c>] (put_files_struct+0x84/0xd8) >> r6:00000001 r5:00000000 r4:86d59000 r3:00000000 >> [<8001c6a8>] (put_files_struct+0x0/0xd8) from [<8001c7a8>] (exit_files+0x28/0x2c) >> r8:8000e564 r7:000000f8 r6:76ef1770 r5:00000100 r4:86d82000 >> r3:86d59000 >> [<8001c780>] (exit_files+0x0/0x2c) from [<8001dab4>] (do_exit+0x1fc/0x688) >> [<8001d8b8>] (do_exit+0x0/0x688) from [<8001dfc0>] (do_group_exit+0x80/0xac) >> r7:000000f8 >> [<8001df40>] (do_group_exit+0x0/0xac) from [<8001e004>] (sys_exit_group+0x18/0x24) >> r4:000a3d78 r3:0000ffff >> [<8001dfec>] (sys_exit_group+0x0/0x24) from [<8000e3e0>] (ret_fast_syscall+0x0/0x30) >> Code: 05852024 e5941268 e5940264 e2842f99 (e5810000) >> ument >> ---[ end trace 23ac1073b67b7fc0 ]--- >> Fixing recursive fault but reboot is needed! >> >> Unfortunately I do not have enough knowledge in this kind of problems, any help will be welcomed. >> >> Regards, >> Alex >> >> >> >> >> >> >> >> >> >> > > --- > Guennadi Liakhovetski, Ph.D. > Freelance Open-Source Software Developer > http://www.open-technology.de/ > -- > To unsubscribe from this list: send the line "unsubscribe linux-media" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
