From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:60107) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SFb3k-0004dH-EJ for qemu-devel@nongnu.org; Wed, 04 Apr 2012 21:00:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SFb3Q-0008E9-Bd for qemu-devel@nongnu.org; Wed, 04 Apr 2012 21:00:19 -0400 Received: from e23smtp07.au.ibm.com ([202.81.31.140]:59748) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SFb3P-0008DK-OT for qemu-devel@nongnu.org; Wed, 04 Apr 2012 21:00:00 -0400 Received: from /spool/local by e23smtp07.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 5 Apr 2012 00:53:16 +1000 Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q350xZSd1020044 for ; Thu, 5 Apr 2012 10:59:35 +1000 Received: from d23av02.au.ibm.com (loopback [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q350xZnP001141 for ; Thu, 5 Apr 2012 10:59:35 +1000 Date: Thu, 5 Apr 2012 00:24:58 +1000 From: David Gibson Message-ID: <20120404142458.GB19379@truffala.fritz.box> References: <1333339457-13854-1-git-send-email-david@gibson.dropbear.id.au> <4F7AA1E0.2070201@web.de> <20120404011238.GC17423@truffala.fritz.box> <4F7C295D.8090202@siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4F7C295D.8090202@siemens.com> Subject: Re: [Qemu-devel] [PATCH, RESEND] kvm: Fix dirty tracking with large kernel page size List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: aliguori@us.ibm.com, mtosatti@redhat.com, qemu-devel@nongnu.org, Avi Kivity On Wed, Apr 04, 2012 at 12:58:37PM +0200, Jan Kiszka wrote: > On 2012-04-04 03:12, David Gibson wrote: > >> Also, what's about coalesced MMIO? I see that the ring definition > >> depends on [TARGET_]PAGE_SIZE. What page size does the power kernel use > >> for it, and does it make a relevant difference for space? > > > > Hr, so the HV variant of Power KVM doesn't do coalesced mmio. The PR > > variant does, but I don't know enough about it to easily answer that. > > If there's a bug there, it hasn't bitten yet, so how about we fix that > > another day. > > Not really a smart approach, specifically now that we are aware of a > potential problem here. My point is that the fact that there may be another bug out there should sure as hell not hold up putting this bug fix in. The bugs may have similar causes and solutions, but they're entirely different code paths and the other fix will in no way replace or subsume this one. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson