Problems with IDE CF - SMP (PREEMPT)

Problems with IDE CF - SMP (PREEMPT)

[Roger Larsson]

Note that since ide-cs has problems with SMP it will have problems with 
PREEMPT as well...

A now old report...
http://pcmcia-cs.sourceforge.net/cgi-bin/HyperNews/get/pcmcia/ide/28.html?nogifs

I have seen problems like this recently (2.4.21) and thought I have read this
somewhere more recent - but can not find it. I will create a bug report.
(Summary: Freezes with SMP, same kernel works with option nosmp)
Remember that drivers that are not SMP safe won't be PREEMPT safe either.

Anyway there are interrupt related PCMCIA problems...
http://sourceforge.net/tracker/?group_id=2405&atid=102405

/RogerL

-- 
Roger Larsson
Skellefteå
Sweden

Re: Problems with IDE CF - SMP (PREEMPT)

[David Hinds]

On Sat, Jan 31, 2004 at 02:50:57AM +0100, Roger Larsson wrote:
> Note that since ide-cs has problems with SMP it will have problems with 
> PREEMPT as well...

This is almost certainly not a problem with the ide-cs driver.

> A now old report...
> http://pcmcia-cs.sourceforge.net/cgi-bin/HyperNews/get/pcmcia/ide/28.html?nogifs

This is not the same problem.

> I have seen problems like this recently (2.4.21) and thought I have
> read this somewhere more recent - but can not find it. I will create
> a bug report.  (Summary: Freezes with SMP, same kernel works with
> option nosmp) Remember that drivers that are not SMP safe won't be
> PREEMPT safe either.

The ide-cs driver is just a teeny wrapper that tells the regular
kernel IDE subsystem to do all the work.  The kernel IDE driver is
presumably SMP safe.

You will have to give much more information to have any hope of
resolving this problem.  My first guess would be that you have a
problem with routing of the PCMCIA bridge interrupt.

- Dave