* [parisc-linux] Console Kernel Panic
@ 2005-12-20 3:50 Keven Tipping
2005-12-20 16:42 ` Matthew Wilcox
2005-12-20 16:42 ` Matthew Wilcox
0 siblings, 2 replies; 3+ messages in thread
From: Keven Tipping @ 2005-12-20 3:50 UTC (permalink / raw)
To: parisc-linux
Greetings to all!
I am currently running Kernel version 2.6.15-rc6-pa1.
This problem, however, is evident in 2.6.14.3-pa0, and 2.6.15-rc5-pa5, as well as 2.6.12.2 (Gentoo 2005 LiveCD). Problem remains regardless of SMP or Uniprocessor kernels.
On the K Class (it appears it is limited to these machines?), if nothing is currently running on the ttyB0 Serial Console, if you press any key, the system burps up the following:
Kernel Panic: Kernel Fault
Not Syncing...
What I mean by "nothing running" is if Agetty is NOT running, NOR is Bash.
This "Gap" where nothing is running, is most evident when you quit Bash (mycomp# exit), and before Agetty has respawned for a login. Inbetween these two events, if any input is sent on the keyboard, the system panics and dies.
I'm not sure what the problem is- maybe related to the MUX driver somehow? Afaik only ttyB0 serial consoles are effected.
Cheers!
Keven Tipping
_______________________________________________
parisc-linux mailing list
parisc-linux@lists.parisc-linux.org
http://lists.parisc-linux.org/mailman/listinfo/parisc-linux
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [parisc-linux] Console Kernel Panic
2005-12-20 3:50 [parisc-linux] Console Kernel Panic Keven Tipping
@ 2005-12-20 16:42 ` Matthew Wilcox
2005-12-20 16:42 ` Matthew Wilcox
1 sibling, 0 replies; 3+ messages in thread
From: Matthew Wilcox @ 2005-12-20 16:42 UTC (permalink / raw)
To: Keven Tipping; +Cc: linux-serial, parisc-linux
On Mon, Dec 19, 2005 at 08:50:18PM -0700, Keven Tipping wrote:
> I am currently running Kernel version 2.6.15-rc6-pa1.
>
> This problem, however, is evident in 2.6.14.3-pa0, and 2.6.15-rc5-pa5, as well as 2.6.12.2 (Gentoo 2005 LiveCD). Problem remains regardless of SMP or Uniprocessor kernels.
>
> On the K Class (it appears it is limited to these machines?), if nothing is currently running on the ttyB0 Serial Console, if you press any key, the system burps up the following:
>
> Kernel Panic: Kernel Fault
> Not Syncing...
>
> What I mean by "nothing running" is if Agetty is NOT running, NOR is Bash.
I really think you could have provided the useful bits from a kernel panic
here. Please see http://www.parisc-linux.org/faq/kernelbug-howto.html
However, I've reproduced it myself. Here's the relevant bits:
IAOQ[0]: mux_read+0x4c/0x17c
IAOQ[1]: mux_read+0x50/0x17c
RP(r2): mux_poll+0x78/0x88
The instruction faulting is:
4c: 48 94 02 28 ldw 114(,r4),r20
which corresponds to the load of flip.count:
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
continue;
ie the 'tty' variable is NULL at this point.
Alan, you seem to have the tarbaby for ttys at the moment ... any idea
why port->info->tty would be NULL? The corresponding routine in 8250.c
(receive_chars()) doesn't check for tty being NULL. So is there
some non-obvious check the MUX driver is missing, or is this a latent
problem in 8250 too?
_______________________________________________
parisc-linux mailing list
parisc-linux@lists.parisc-linux.org
http://lists.parisc-linux.org/mailman/listinfo/parisc-linux
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [parisc-linux] Console Kernel Panic
2005-12-20 3:50 [parisc-linux] Console Kernel Panic Keven Tipping
2005-12-20 16:42 ` Matthew Wilcox
@ 2005-12-20 16:42 ` Matthew Wilcox
1 sibling, 0 replies; 3+ messages in thread
From: Matthew Wilcox @ 2005-12-20 16:42 UTC (permalink / raw)
To: Keven Tipping; +Cc: parisc-linux, linux-serial, Alan Cox
On Mon, Dec 19, 2005 at 08:50:18PM -0700, Keven Tipping wrote:
> I am currently running Kernel version 2.6.15-rc6-pa1.
>
> This problem, however, is evident in 2.6.14.3-pa0, and 2.6.15-rc5-pa5, as well as 2.6.12.2 (Gentoo 2005 LiveCD). Problem remains regardless of SMP or Uniprocessor kernels.
>
> On the K Class (it appears it is limited to these machines?), if nothing is currently running on the ttyB0 Serial Console, if you press any key, the system burps up the following:
>
> Kernel Panic: Kernel Fault
> Not Syncing...
>
> What I mean by "nothing running" is if Agetty is NOT running, NOR is Bash.
I really think you could have provided the useful bits from a kernel panic
here. Please see http://www.parisc-linux.org/faq/kernelbug-howto.html
However, I've reproduced it myself. Here's the relevant bits:
IAOQ[0]: mux_read+0x4c/0x17c
IAOQ[1]: mux_read+0x50/0x17c
RP(r2): mux_poll+0x78/0x88
The instruction faulting is:
4c: 48 94 02 28 ldw 114(,r4),r20
which corresponds to the load of flip.count:
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
continue;
ie the 'tty' variable is NULL at this point.
Alan, you seem to have the tarbaby for ttys at the moment ... any idea
why port->info->tty would be NULL? The corresponding routine in 8250.c
(receive_chars()) doesn't check for tty being NULL. So is there
some non-obvious check the MUX driver is missing, or is this a latent
problem in 8250 too?
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2005-12-20 16:42 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2005-12-20 3:50 [parisc-linux] Console Kernel Panic Keven Tipping
2005-12-20 16:42 ` Matthew Wilcox
2005-12-20 16:42 ` Matthew Wilcox
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.