From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48757) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cqi1i-0004bf-7R for qemu-devel@nongnu.org; Wed, 22 Mar 2017 11:18:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cqi1e-0008OJ-4v for qemu-devel@nongnu.org; Wed, 22 Mar 2017 11:18:18 -0400 Received: from mail-qk0-x243.google.com ([2607:f8b0:400d:c09::243]:35875) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cqi1d-0008O5-TT for qemu-devel@nongnu.org; Wed, 22 Mar 2017 11:18:14 -0400 Received: by mail-qk0-x243.google.com with SMTP id n141so26504627qke.3 for ; Wed, 22 Mar 2017 08:18:13 -0700 (PDT) Date: Wed, 22 Mar 2017 11:18:10 -0400 From: Kevin O'Connor Message-ID: <20170322151810.GA17564@morn.lan> References: <87bmstu19t.fsf@dusky.pond.sub.org> <1f744cad-f67b-92d3-b4e4-32f8b05c643c@redhat.com> <20170322132549.3d7e2a49@nial.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20170322132549.3d7e2a49@nial.brq.redhat.com> Subject: Re: [Qemu-devel] [SeaBIOS] Minimum RAM size for PC machines? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Mammedov Cc: Thomas Huth , Peter Maydell , seabios@seabios.org, =?iso-8859-1?B?TOFzemzzIMlyc2Vr?= , Markus Armbruster , qemu-devel@nongnu.org On Wed, Mar 22, 2017 at 01:25:49PM +0100, Igor Mammedov wrote: > On Wed, 22 Mar 2017 11:03:44 +0100 > Thomas Huth wrote: > > On 22.03.2017 10:08, Markus Armbruster wrote: > > > Are we now ready to accept a simple & stupid patch that actually helps > > > users, say letting boards that care declare minimum and maximum RAM > > > size? And make PC reject RAM size less than 1MiB, even though "someone" > > > might conceivably have firmware that works with less? > > > > I'd say enforce a minimum RAM size on the normal "pc" and "q35" machine, > > but still allow smaller sizes on the "isapc" machine. So if "someone" > > comes around and claims to have a legacy firmware that wants less memory > > than 1MiB, just point them to the isapc machine. > > Just my 0.02 €. > > We can print warning that minimum size will be enforced in 1-2 > releases since 2.9/10 and when it's enforced send users that need > less to an old qemu version. I did not think that QEMU ever worked on an x86 machine with less than 1MiB of ram. Certainly SeaBIOS has never supported it. I'm pretty sure that Bochs BIOS (qemu < v0.12) did not support it either - its ram detection system assumed a minimum of 1MiB. My $.02 - I agree with Markus - place a minimum limit of 1MiB on x86 machines. If someone is writing a new firmware, updating QEMU to change the limit is the very least of their concerns. -Kevin