Re: Device hang when offlining a CPU due to IRQ misrouting

["Siddha, Suresh B" <suresh.b.siddha@intel.com>]

On Mon, Jun 18, 2007 at 03:38:20PM -0700, Darrick J. Wong wrote:
> On Thu, Jun 07, 2007 at 05:57:26PM -0700, Siddha, Suresh B wrote:
> 
> > As you have the failing system, you need to do more detective work and
> > help me out. Can you try this debug patch and send across the dmesg after the
> > bug happens and also can you try different compiler to see if something
> > changes..
> 
> Hrm, I just updated to -rc5.  Interrupts being handled by the IOAPIC
> don't suffer from this problem, but MSI interrupts are still affected.
> I added a few printks to the kernel to figure out what IRQ affinity
> masks were being passed around and saw this:
> 
> [  256.298773] Breaking affinity for irq 4341
> [  256.298774] irq=4341 affinity=2 mask=d
> <call to set_affinity>
> [  256.298787] irq=4341 affinity=d
> <ethernet on irq 4341 stops working>

And just to make sure, at this point, your MSI irq 4341 affinity
(/proc/irq/4341/smp_affinity) still points to '2'?

> I'll keep digging, but at least it appears that the problem has been
> shrunk down to something the MSI code.

thanks,
suresh