On Tuesday 02 September 2008, Takashi Iwai wrote:

At Tue, 2 Sep 2008 12:41:32 +0200,
Bartlomiej Zolnierkiewicz wrote:

quoted

On Tuesday 02 September 2008, Alan Cox wrote:

quoted

quoted

Still happens with next-20080901, also upon closer look it is not
just an innocent trace dump as /proc/sys/kernel/pty/ dir and its
content are gone.

That would not surprise me. The 0901 tree would have been built at the end of the weekend. I don't actually work 7 days a week, but 5.

I've pushed that (including a new implementation of the needed field) tonight.

Thanks, the trace dump is no longer there in next-20080902.

However now I'm getting the fully-fledged kernel panic...

BUG: unable to handle kernel NULL pointer dereference at 0000000c
IP: [<c0219cc6>] n_tty_set_termios+0x12/0x2de
*pde = 00000000
Oops: 0000 [#1] PREEMPT
last sysfs file:
Modules linked in:

Pid: 1, comm: swapper Tainted: G        W (2.6.27-rc5-next-20080902 #198)
EIP: 0060:[<c0219cc6>] EFLAGS: 00000286 CPU: 0
EIP is at n_tty_set_termios+0x12/0x2de
EAX: 00008a3b EBX: c78ce800 ECX: c78ce800 EDX: 00000000
ESI: 00000000 EDI: c7904000 EBP: 00000000 ESP: c7820e48
 DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
Process swapper (pid: 1, ti=c7820000 task=c781fcc0 task.ti=c7820000)
Stack: c78ce800 c7904000 c021bb80 c78ce800 c78ce800 c021cd3f c78ce800 fffffff4
       c785a520 c021980a 00000000 00000000 c785a520 00000000 c78313a0 c0219a22
       c74098dc 00000002 00500001 00000001 00000000 00000000 c0459e5c 00000000
Call Trace:
 [<c021bb80>] n_tty_open+0x71/0x89
 [<c021cd3f>] tty_ldisc_setup+0x15/0x59
 [<c021980a>] tty_init_dev+0xf2/0x135
 [<c0219a22>] tty_open+0x1d5/0x343
 [<c0160db0>] chrdev_open+0x147/0x15d
 [<c0160c69>] chrdev_open+0x0/0x15d
 [<c015d757>] __dentry_open+0x11c/0x204
 [<c015d8cf>] nameidata_to_filp+0x28/0x3b
 [<c0167a14>] do_filp_open+0x35e/0x692
 [<c011cac6>] release_console_sem+0x188/0x1ac
 [<c011cedb>] vprintk+0x23f/0x249
 [<c0117019>] __dequeue_entity+0x1f/0x71
 [<c016e7b6>] alloc_fd+0x5a/0xd6
 [<c015d564>] do_sys_open+0x3f/0xb7
 [<c02fed27>] schedule+0x27e/0x2d9
 [<c015d620>] sys_open+0x1e/0x23
 [<c010123f>] init_post+0x2d/0x16a
 [<c0103a47>] kernel_thread_helper+0x7/0x10
 =======================
Code: e0 25 00 f0 ff ff ff 48 14 f6 40 08 08 74 05 e8 a5 51 0e 00 89 d8 5b 5e c3 57 85 c0 53 89 c3 75 04 0f 0b eb fe 8b 40 28 8b 40 0c <33> 42 0c a8 02 74 56 8d bb 60 01 00 00 b9 80 00 00 00 31 c0 f3
EIP: [<c0219cc6>] n_tty_set_termios+0x12/0x2de SS:ESP 0068:c7820e48
---[ end trace 4eaa2a86a8e2da22 ]---
Kernel panic - not syncing: Attempted to kill init!

The patch below fixes the Oops, at least.

Confirmed, thanks!