From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:34437) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TZ2zL-0008Jk-R0 for qemu-devel@nongnu.org; Thu, 15 Nov 2012 12:12:30 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TZ2zI-0006Qc-PR for qemu-devel@nongnu.org; Thu, 15 Nov 2012 12:12:27 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45134) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TZ2zI-0006QU-Fq for qemu-devel@nongnu.org; Thu, 15 Nov 2012 12:12:24 -0500 Message-ID: <50A51FA0.1070504@redhat.com> Date: Thu, 15 Nov 2012 18:00:16 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <50A0E79F0200009100082E4C@novprvoes0310.provo.novell.com> <50A2250A.4070108@redhat.com> <4B45B535F7F6BE4CB1C044ED5115CDDE012D550D234B@LONPMAILBOX01.citrite.net> <50A3C853.4010809@redhat.com> <50A4B9FB0200009100083093@novprvoes0310.provo.novell.com> In-Reply-To: <50A4B9FB0200009100083093@novprvoes0310.provo.novell.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] block: vpc support for ~2 TB disks List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Charles Arnold Cc: Kevin Wolf , Thanos Makatos , "xen-devel@lists.xensource.com" , Stefano Stabellini , "qemu-devel@nongnu.org" , "stefanha@redhat.com" Il 15/11/2012 17:46, Charles Arnold ha scritto: >>> We don't use qemu's VHD driver in XenServer. Instead, we use blktap2 >>> >> to create a block device in dom0 serving the VHD file in question, >>> >> and have qemu open that block device instead of the VHD file itself. >> > >> > Yes, the question is how you handle disks bigger than 127GB, so that >> > QEMU can do the same. >> > > In analyzing a 160 GB VHD fixed disk image created on Windows 2008 R2, it appears that > MS is also ignoring the CHS values in the footer geometry field in whatever > driver they use for accessing the image. The CHS values are set at 65535,16,255 > which obviously doesn't represent an image size of 160 GB. Thanks, this would have been useful in the commit message. The patch looks good, Reviewed-by: Paolo Bonzini Paolo > This patch only extends the existing qemu driver to allow a larger image by allowing > more heads. On real hardware, only 4 bits would be allowed for heads but we don't > have that restriction in qemu.