Problem with PCMCIA IDE

Problem with PCMCIA IDE

[Akkana Peck]

I've been having problems getting PCMCIA IDE to work on my Vaio
laptop on recent kernels (I've been working most with 2.6.23.1 and
.8). I've been hesitant to report it as a kernel bug because it
may very well be a problem with my .config parameters -- the CDROM
worked in distro kernels back around 2.6.17 and .18, and self-built
kernels even earlier than that, but the configuration has changed
quite a bit since then so it's hard to compare directly and figure
out if I'm missing something.

First, is this a reasonable place to report problems with PCMCIA,
or does it belong on a PCMCIA list?

The machine is a Vaio SR17 and I'm hotplugging a PCMCIA CDROM drive
(this is a subnotebook, so the drive is external).  I don't think
it's CD specific (the CONFIG_BLK_DEV_IDECD code), because /proc/ide
only shows ide0, not ide2 like I'm used to seeing in earlier kernels
when the CD drive was connected.

PCMCIA/Cardbus itself works fine (e.g. for network cards).
There's no sata (this is an old machine).

Depending on how I set kernel options, I can get the kernel to lock
up when the PCMCIA CDROM drive is plugged in, or not. When it locks,
it stays locked up (no keyboard or X events), until I eject the
PCMCIA plug, then after a few seconds things are back to normal.
Either way, it never notices the CD drive or creates an ide2 bus.

In the cases where it locks up, dmesg says:
BUG: soft lockup detected on CPU#0!
 [<c01213b7>] update_process_times+0x27/0x70
 [<c0130e7d>] tick_nohz_handler+0x5d/0xf0
 [<c01069ab>] timer_interrupt+0xb/0x20
 [<c013c795>] handle_IRQ_event+0x25/0x60
 [<c013dd14>] handle_level_irq+0x44/0xa0
 [<c0105d72>] do_IRQ+0x42/0x80
 [<c01041af>] common_interrupt+0x23/0x28
 [<c011dbcd>] __do_softirq+0x2d/0x90
 [<c011dc56>] do_softirq+0x26/0x30
 [<c011df1a>] irq_exit+0x5a/0x60
 [<c0105d77>] do_IRQ+0x47/0x80
 [<c01041af>] common_interrupt+0x23/0x28
 [<c02eb163>] ide_register_hw_with_fixup+0x33/0x1e0
 [<c02fc3d6>] idecs_register+0x76/0x80
[ various more backtrace, then ]
 =======================
Probing IDE interface ide2...

then that last message keeps repeating until I eject.

Since it's obviously complaining about IRQs, I tried turning on
CONFIG_IDEPCI_SHARE_IRQ=y (I also turned off CONFIG_BLK_DEV_IDEACPI
to see if that made any difference) and that stopped the
"BUG: soft lockup", but I still got the loop over "Probing IDE
interface ide2..." and it still doesn't see the CDROM or ide2.

I've put the full .config files at http://shallowsky.com/tmp/configs/
so as not to clutter this list.

Can anybody offer any tips for figuring out whether this is a
config error on my part, or a real kernel bug in IDECS?
Or send me to a more appropriate forum, if this isn't it?

Thanks in advance!

	...Akkana

Re: Problem with PCMCIA IDE

[Alan Cox]

On Sun, 18 Nov 2007 12:23:09 -0800
Akkana Peck <akkana@shallowsky.com> wrote:

> I've been having problems getting PCMCIA IDE to work on my Vaio
> laptop on recent kernels (I've been working most with 2.6.23.1 and
> .8). I've been hesitant to report it as a kernel bug because it
> may very well be a problem with my .config parameters -- the CDROM

Does the same happen if you disable the tickless NOHZ kernel option ?

Alan

Re: Problem with PCMCIA IDE

[Akkana Peck]

Alan Cox writes:
> Akkana Peck <akkana@shallowsky.com> wrote:
> 
> > I've been having problems getting PCMCIA IDE to work on my Vaio
> > laptop on recent kernels (I've been working most with 2.6.23.1 and
> > .8). I've been hesitant to report it as a kernel bug because it
> > may very well be a problem with my .config parameters -- the CDROM
> 
> Does the same happen if you disable the tickless NOHZ kernel option ?

Yes, same behavior without tickless.

Also, I had said that I didn't get the soft lockup if
CONFIG_IDEPCI_SHARE_IRQ=y and I think that's true, but with tickless
disabled I get the soft lockup regardless of the IRQ-sharing setting.

	...Akkana

Re: Problem with PCMCIA IDE

[Bartlomiej Zolnierkiewicz]

Hi,

On Sunday 18 November 2007, Akkana Peck wrote:
> I've been having problems getting PCMCIA IDE to work on my Vaio
> laptop on recent kernels (I've been working most with 2.6.23.1 and
> .8). I've been hesitant to report it as a kernel bug because it
> may very well be a problem with my .config parameters -- the CDROM
> worked in distro kernels back around 2.6.17 and .18, and self-built
> kernels even earlier than that, but the configuration has changed
> quite a bit since then so it's hard to compare directly and figure
> out if I'm missing something.

[...]

Is the problem still present in 2.6.24-rc3?

It would greatly help if you could narrow it down to the specific
commit which introduced the bug (using git-bisect), or (for a start)
to a specific kernel version.

Thanks,
Bart