From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: Debugging an inconsistent shadow page table
Date: Sun, 26 Apr 2009 14:27:49 +0300
Message-ID: <20090426112749.GT24095@redhat.com>
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Cc: Avi Kivity <avi@redhat.com>, kvm-devel <kvm@vger.kernel.org>
To: Jan Kiszka <jan.kiszka@web.de>
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On Sun, Apr 26, 2009 at 01:11:40PM +0200, Jan Kiszka wrote:
> That raise a question for a kvm-mmu newbie like me:
> 
> If a page of the qemu process gets pushed around (here likely due to
> fork()->exec(smbd)->COW), how will kvm's shadow table catch up? Via
> MMU_NOTIFIER?
> 
> I'm on a 2.6.25 kernel, and that means without CONFIG_MMU_NOTIFIER. So
> far I assumed that kernels without this feature do not work optimally,
> but they won't break my guests...
> 
Guest memory is not COWed on fork (madvise(MADV_DONTFORK))

--
			Gleb.