Re: Oops when modprobing ivtv outside of dom0

[David Muench <davemuench@gmail.com>]

On 7/5/05, Keir Fraser <Keir.Fraser@cl.cam.ac.uk> wrote:
> Ah, I see the bug. It's in both 2.0 and 3.3 (the unstable version) so
> it's worth pointing out to the developers. The following code in
> ivtv_setup_pci() is broken:

Thanks, that fixed the loading problem, it now detects all the cards
properly. However, when I try to read some video from the card (you
can just cat /dev/video0 > file.mpg) it crashes the entire domU:

neptune ~ # cat /dev/video0 > test.mpg
Oops: 0000 [#1]
Modules linked in: msp3400 saa7115 tuner tveeprom ivtv i2c_algo_bit
videodev ehci_hcd uhci_hcd usbcore
CPU:    0
EIP:    0061:[<b6f92126>]    Not tainted VLI
EFLAGS: 00010282   (2.6.11-xenU)
EIP is at 0xb6f92126
eax: d08cfbc0   ebx: 00001000   ecx: 0007dfc0   edx: cbbe3fac
esi: 00000000   edi: c0792c80   ebp: 0804d080   esp: cbbe3f74
ds: 007b   es: 007b   ss: 0069
Process cat (pid: 5522, threadinfo=cbbe3000 task=cdf7da00)
Stack: c015133e c0792c80 0804d080 00001000 cbbe3fac c0792c80 fffffff7 0804d080
       cbbe3000 c0151631 c0792c80 0804d080 00001000 cbbe3fac 0007dfc0 00000000
       00000000 00000003 fbffc000 c0109040 00000003 0804d080 00001000 00001000
Call Trace:
 [<c015133e>] vfs_read+0xae/0x130
 [<c0151631>] sys_read+0x51/0x80
 [<c0109040>] syscall_call+0x7/0xb
Code:  Bad EIP value.
 <1>Unable to handle kernel paging request at virtual address 761853ac
 printing eip:
761853ac
*pde = ma 00000000 pa 55555000
 [<c011a874>] put_files_struct+0x64/0xd0
 [<c011b46f>] do_exit+0xaf/0x2b0
 [<c0110069>] sys_ptrace+0x89/0x610
 [<c010999d>] die+0x16d/0x170
 [<c0109040>] syscall_call+0x7/0xb
 [<c0113138>] do_page_fault+0x318/0x693
 [<c0187994>] ext3_file_write+0x44/0xd0
 [<c0151477>] do_sync_write+0xb7/0xf0
 [<c01093ff>] page_fault+0x3b/0x40
 [<c015133e>] vfs_read+0xae/0x130
 [<c0151631>] sys_read+0x51/0x80
 [<c0109040>] syscall_call+0x7/0xb
Oops: 0000 [#2]
Modules linked in: msp3400 saa7115 tuner tveeprom ivtv i2c_algo_bit
videodev ehci_hcd uhci_hcd usbcore
CPU:    0
EIP:    0061:[<761853ac>]    Not tainted VLI
EFLAGS: 00010206   (2.6.11-xenU)
EIP is at 0x761853ac
eax: d08cfbc0   ebx: c0792c80   ecx: c08e3780   edx: 761853ac
esi: 00000000   edi: cfb8a680   ebp: 00000001   esp: cbbe3dd4
ds: 0069   es: 0069   ss: 0069
Process cat (pid: 5522, threadinfo=cbbe3000 task=cdf7da00)
Stack: c0150b26 c0792c80 cfb8a680 00000001 00000003 cfb8a680 c011a874 c0792c80
       cfb8a680 cbbe3000 cdf7da00 0000000b 00000001 c011b46f cdf7da00 00000069
       c0110069 00000012 cbbe3000 00000000 00000000 c078b22c c010999d 00000000
Call Trace:
 [<c0150b26>] filp_close+0x76/0x90
 [<c011a874>] put_files_struct+0x64/0xd0
 [<c011b46f>] do_exit+0xaf/0x2b0
 [<c0110069>] sys_ptrace+0x89/0x610
 [<c010999d>] die+0x16d/0x170
 [<c0109040>] syscall_call+0x7/0xb
 [<c0113138>] do_page_fault+0x318/0x693
 [<c0187994>] ext3_file_write+0x44/0xd0
 [<c0151477>] do_sync_write+0xb7/0xf0
 [<c01093ff>] page_fault+0x3b/0x40
 [<c015133e>] vfs_read+0xae/0x130
 [<c0151631>] sys_read+0x51/0x80
 [<c0109040>] syscall_call+0x7/0xb
Code:  Bad EIP value.
 Segmentation fault
neptune ~ #
************ REMOTE CONSOLE EXITED *****************

Any ideas on that one? :) If we're getting out of the realm of Xen and
I should go ask the IVTV guys, please don't hesitate to say so.

I just tried a second time, and it took a few tries of capturing video
to crash it. But even when it didn't crash, all I got was a zero byte
file. I noticed the card was using interrupts (looking at
/proc/interrupts), and things looked ok in dmesg, but no mpeg data.
That time the domU didn't exit on it's own, but was pretty well hung
up (non-responsive other than line feeds on the console). So I tried
to xm destroy it, and that rebooted the entire box.

Thanks,
Dave

-- 
David Muench - davemuench@gmail.com
Jabber ID: dave@jabber.wasteland.org