[Xen-devel] problems with console in domU if physdev access enabled

[Maurice Meeden <tux@xxxxxxxx>]

Hi,

I am trying to build a working domU kernel with CONFIG_XEN_PHYSDEV_ACCESS=y. But
if this enabled, domU fails to boot with different errors about the console.
With kernel 2.6.10 and xen 2.0.5 this error occurs if I try to start the Domain:
..
WARNING: Failed to register Xen virtual console driver as 'tty1'
..
Warning: unable to open an initial console.
Unable to handle kernel NULL pointer dereference at virtual address 00000000
 printing eip:
c0264852
*pde = ma 00000000 pa 55555000
 [<c0264a41>] vc_allocate+0xa1/0x1b0
 [<c0268028>] con_open+0x48/0xc0
 [<c02578dd>] tty_open+0x24d/0x2d0
 [<c0257690>] tty_open+0x0/0x2d0
 [<c015e8da>] chrdev_open+0xea/0x1d0
 [<c01547ba>] dentry_open+0x15a/0x240
 [<c0154658>] filp_open+0x68/0x70
 [<c01548d9>] get_unused_fd+0x39/0xe0
 [<c0154a49>] sys_open+0x49/0x90
 [<c0109648>] syscall_call+0x7/0xb
Oops: 0000 [#1]
PREEMPT 
Modules linked in:
CPU:    0
EIP:    0061:[<c0264852>]    Not tainted VLI
EFLAGS: 00010246   (2.6.10-xenU) 
EIP is at visual_init+0x72/0x1c0
eax: 00000000   ebx: c00c4e00   ecx: 00000000   edx: c00c4e00
esi: 00000000   edi: 00000001   ebp: 00000000   esp: c10a9e94
ds: 007b   es: 007b   ss: 0069
Process init (pid: 1, threadinfo=c10a8000 task=c00139e0)
Stack: 00000000 000000d0 c00c4e00 00000000 c0264a41 00000000 00000001 00000000 
       c009bc20 00000000 00000000 c115e000 00400000 c0268028 00000000 c03c6e00 
       c00ab880 00000001 c02578dd c115e000 c00ab880 c10a9ef0 00000102 c115e000 
Call Trace:
 [<c0264a41>] vc_allocate+0xa1/0x1b0
 [<c0268028>] con_open+0x48/0xc0
 [<c02578dd>] tty_open+0x24d/0x2d0
 [<c0257690>] tty_open+0x0/0x2d0
 [<c015e8da>] chrdev_open+0xea/0x1d0
 [<c01547ba>] dentry_open+0x15a/0x240
 [<c0154658>] filp_open+0x68/0x70
 [<c01548d9>] get_unused_fd+0x39/0xe0
 [<c0154a49>] sys_open+0x49/0x90
 [<c0109648>] syscall_call+0x7/0xb
Code: 40 b8 39 c0 a1 2c b8 39 c0 89 42 28 8b 14 b5 80 c9 39 c0 85 d2 74 0a 8b 04
b5 40 b8 39 c0 89 50 28 8b 14 b5 40 b8 39 c0 8b 42 28 <8b> 18 85 db 74 35 89 1c
 24 e8 90 bd ec ff 85 c0 0f 84 09 01 00 
 <0>Kernel panic - not syncing: Attempted to kill init!
 <0>Rebooting in 1 seconds..

With 2.0-testing (snapshot from yesterday) there is no output if I try to start
the domain:
Using config file "tty.cfg".
Started domain ttylinux, console on port 9608
************ REMOTE CONSOLE: CTRL-] TO QUIT ********

Ive tried various kernel-configurations an also played with the xencons Options,
but in any cases the Domain does not booting. If I switch physdev access off,
the domain runs with the same kernelconfig without problems. I'm using Gentoo
Linux stable with gcc-3.3.5, glibc 2.3.4.20040808-r1 without ntpl. Xen was build
from Source as it is described in the documentation.

Is here anybody who has xen running with physdev acces in one of the domU's? Or
is there anything what must make different when physdev-access is enabled?

Thanks in advance and please excuse my bad english ;-)
Maurice



-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now.
http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/xen-devel