From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nathan March <nathan@gt.net>
Subject: 4.1.1 dom0 kernel panic "No available IRQ to bind to:
	increae nr_irqs!"
Date: Mon, 22 Aug 2011 13:22:06 -0700
Message-ID: <4E52BA6E.5000409@gt.net>
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Hi,

I've run into an issue where after spawning more than ~22 VMs, the dom0
will panic with:

Kernel panic - not syncing: No available IRQ to bind to: increase nr_irqs!

xen7 ~ # dmesg | grep IRQ
[   40.430664] NR_IRQS:4352 nr_irqs:512

This is on xen 4.1.1 with the 2.6.32.43 kernel from jeremy xen.git.

I do have sparse IRQ's on:
 CONFIG_SPARSE_IRQ=y

I've found numerous comments about this online, but they primarily seem
to apply to earlier versions of xen. More recent comments seem to
indicate it shouldn't be a problem since the IRQ's are dynamically
increased? The kernel doesn't seem to have NR_IRQS specified anywhere
that I can see...

Can anyone point me in the right direction to resolve this?

Thanks,
Nathan