From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sasha Levin <sasha.levin@oracle.com>
Subject: Re: [PATCH] kvm tools: fix boot of guests with more than 4gb of ram
Date: Tue, 25 Jun 2013 13:02:13 -0400
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Cc: penberg@kernel.org, will.deacon@arm.com, kvm@vger.kernel.org
To: Michael Ellerman <michael@ellerman.id.au>
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On 06/24/2013 08:58 PM, Michael Ellerman wrote:
> On Sun, 2013-06-23 at 21:23 -0400, Sasha Levin wrote:
>> Commit "kvm tools: virtio: remove hardcoded assumptions
>> about guest page size" has introduced a bug that prevented
>> guests with more than 4gb of ram from booting.
>>
>> The issue is that 'pfn' is a 32bit integer, so when multiplying
>> it by page size to get the actual page will cause an overflow if
>> the pfn referred to a memory area above 4gb.
>
> Couldn't we just make pfn 64 bit?

pfn is passed to us by the guest virtio driver, and is 32 bit.


Thanks,
Sasha