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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH] limit guest cpus for kvm enabled builds
Date: Thu, 9 Apr 2009 17:05:19 +0100
References: <49DDC4160200004800071C73@lucius.provo.novell.com>
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To: qemu-devel@nongnu.org
Cc: Bruce Rogers <brogers@novell.com>

On Thursday 09 April 2009, Bruce Rogers wrote:
> The x86 kvm kernel module limits guest cpu count to 16, but the userspace
> pc definition says 255 still.  When invoking qemu-kvm with -smp > 16, it
> prints some error messages, then segfaults.   One of the mistakes is that
> the error code from kvm_create_vcpu is ignored in ap_main_loop. 

You should fix that bug then.

> This patch will enforce the limit at initialization time and avoid these
> problems from the get go.

No. We still want to support a decent number of cpus when -no-kvm is 
specified.

Paul