Comment 18 for bug 659348

Update: 2.6.35-23-generic does not fix this problem.

Here's the relevant section of the dmesg. If anyone working on this would like to see any other log, let me know. This is with a Hauppauge 1800 PVR card. This happens as soon as the video capture is started in MythTV. Either with "Watch Live TV" or when a scheduled recording starts. It works with ppa 2.6.35-02063508-generic, but I haven't found any other ppa builds that are stable on this machine.

[ 102.185705]
[ 102.185719] Pid: 2074, comm: cx23885[0] dvb Not tainted 2.6.35-23-generic #41-Ubuntu M2NBP-VM CSM/System Product Name
[ 102.185730] RIP: 0010:[<ffffffffa0172563>] [<ffffffffa0172563>] videobuf_dma_unmap+0x43/0xb0 [videobuf_dma_sg]
[ 102.185749] RSP: 0018:ffff8801a536ddc0 EFLAGS: 00010246
[ 102.185756] RAX: 0000010100000000 RBX: ffff88018bd9e4f8 RCX: 0000000000000002
[ 102.185764] RDX: 0000000000000006 RSI: ffffc900117e2000 RDI: ffff8801a8a850a0
[ 102.185772] RBP: ffff8801a536ddd0 R08: 0000000000000000 R09: 00000000ffffffff
[ 102.185780] R10: 00000000ffffffff R11: 0000000000000001 R12: ffff88019e461828
[ 102.185788] R13: ffff88018bd9e4f8 R14: ffff88019e461828 R15: ffff88018be00000
[ 102.185797] FS: 00007f8f74dfa710(0000) GS:ffff880001f00000(0000) knlGS:0000000000000000
[ 102.185805] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 102.185813] CR2: 0000010100000028 CR3: 0000000194008000 CR4: 00000000000006e0
[ 102.185821] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 102.185829] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 102.185839] Process cx23885[0] dvb (pid: 2074, threadinfo ffff8801a536c000, task ffff88018be00000)
[ 102.185846] Stack:
[ 102.185853] ffff88018bd9e4f8 ffff88018bd9e400 ffff8801a536de00 ffffffffa020f12a
[ 102.185871] <0> ffff8801a536ddf0 ffff88019e461828 ffff88019e461828 ffff88019e461928
[ 102.185892] <0> ffff8801a536de10 ffffffffa0210d5e ffff8801a536de40 ffffffffa0084457
[ 102.185916] Call Trace:
[ 102.185954] [<ffffffffa020f12a>] cx23885_free_buffer+0x5a/0xa0 [cx23885]
[ 102.185974] [<ffffffffa0210d5e>] dvb_buf_release+0xe/0x10 [cx23885]
[ 102.185994] [<ffffffffa0084457>] videobuf_queue_cancel+0xf7/0x120 [videobuf_core]
[ 102.186009] [<ffffffffa00844e7>] __videobuf_read_stop+0x17/0x70 [videobuf_core]
[ 102.186024] [<ffffffffa008455e>] videobuf_read_stop+0x1e/0x30 [videobuf_core]
[ 102.186039] [<ffffffffa016a8c8>] videobuf_dvb_thread+0x168/0x1e0 [videobuf_dvb]
[ 102.186053] [<ffffffffa016a760>] ? videobuf_dvb_thread+0x0/0x1e0 [videobuf_dvb]
[ 102.186068] [<ffffffff8107f0c6>] kthread+0x96/0xa0
[ 102.186082] [<ffffffff8100aee4>] kernel_thread_helper+0x4/0x10
[ 102.186092] [<ffffffff8107f030>] ? kthread+0x0/0xa0
[ 102.186102] [<ffffffff8100aee0>] ? kernel_thread_helper+0x0/0x10
[ 102.186109] Code: 19 75 6e 8b 53 28 85 d2 74 4b 48 8b 7f 28 8b 4b 30 48 8b 73 20 48 85 ff 74 4e 48 8b 87 e8 01 00 00 48 85 c0 74 42 83 f9 02 77 5d <48> 8b 40 28 48 85 c0 74 0a 45 31 c0 90 ff d0 48 8b 73 20 48 89
[ 102.186334] RIP [<ffffffffa0172563>] videobuf_dma_unmap+0x43/0xb0 [videobuf_dma_sg]
[ 102.186350] RSP <ffff8801a536ddc0>
[ 102.186357] CR2: 0000010100000028
[ 102.186365] ---[ end trace 005b6f61f1432205 ]---