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Date: Mon, 27 Jun 2011 17:11:52 +0300
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [RFC v2 03/20] memory: merge adjacent segments of
 a single memory region
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org

On 06/27/2011 04:56 PM, Jan Kiszka wrote:
> On 2011-06-27 15:21, Avi Kivity wrote:
> >  Simple implementations of memory routers, for example the Cirrus VGA memory banks
> >  or the 440FX PAM registers can generate adjacent memory regions which are contiguous.
> >  Detect these and merge them; this saves kvm memory slots and shortens lookup times.
>
> That reminds me of KVM_CAP_JOIN_MEMORY_REGIONS_WORKS. Have you checked
> if things still work in the absence of the feature or if we need to lift
> our requirements on the host kernel (would be 2.6.30, not that problematic)?

Good catch.

We should probably disable merging if it doesn't work.  Or we should 
declare that a kernel bug should be fixed in the kernel, not userspace, 
and backport the fix to 2.6.27.whatever.

-- 
error compiling committee.c: too many arguments to function