From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LMQoy-0004XS-MO for qemu-devel@nongnu.org; Mon, 12 Jan 2009 12:43:28 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LMQow-0004XA-BR for qemu-devel@nongnu.org; Mon, 12 Jan 2009 12:43:27 -0500 Received: from [199.232.76.173] (port=45122 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LMQow-0004X7-5J for qemu-devel@nongnu.org; Mon, 12 Jan 2009 12:43:26 -0500 Received: from smtp.eu.citrix.com ([62.200.22.115]:23466) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1LMQov-0001Os-O1 for qemu-devel@nongnu.org; Mon, 12 Jan 2009 12:43:25 -0500 Message-ID: <496B8135.4000304@eu.citrix.com> Date: Mon, 12 Jan 2009 12:43:17 -0500 From: Trolle Selander MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH] [RFC] Variable video ram size option References: <4967A96B.3020902@eu.citrix.com> <4969A57D.2020708@redhat.com> In-Reply-To: <4969A57D.2020708@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Avi Kivity Cc: qemu-devel@nongnu.org Avi Kivity wrote: > Trolle Selander wrote: >> These patches are "extracted" from a patch-set I made for Xen. Any >> xen-specific parts have been removed. The patches do away with the >> statically defined VGA_RAM_ SIZE and provides a new -videoram option >> to enable setting the amount of video ram available to the VM. >> Shrinking default video ram used to 4 Megs (which is all that the >> default Cirrus card can use, anyway - previously, there's been a >> "waste" of 4 megs with the statically defined 8 Megs), but allowing >> users to specify up to 16 Megs of vram, to support the very high >> resolutions such as 2560x1600x32 that are available on today's >> high-end displays. >> The vgabios patch is needed for this to work, both for the variable >> size video ram, and to add the new resolutions. The defines for the >> high resolution and wide-screen modes were taken from what is already >> in qemu-kvm, so getting this into qemu mainline should get qemu/kvm & >> xen "in sync" in this regard. >> >> Special thanks to Stefano Stabellini for comments & constructive >> criticism, and some save/restore fixes on the Xen version of this >> patch-set. >> >> I'll brace myself for reports of how this patch breaks all the >> non-x86 architectures that qemu emulates... :) >> @@ -178,7 +178,7 @@ >> to store the VM snapshots */ >> DriveInfo drives_table[MAX_DRIVES+1]; >> int nb_drives; >> -static int vga_ram_size; >> +static int vga_ram_size = 4 * 1024 * 1024; >> enum vga_retrace_method vga_retrace_method = VGA_RETRACE_DUMB; >> DisplayState display_state; >> int nographic; > > You're changing the default, which will break existing setups. > My bad. That was actually a small xen "leftover", where the previous default for stdvga didn't matter, since VBE had never been enabled and the 8 megs allocated for it by default had never actually been used, so it was "safe" to break the default there. The probably shouldn't be a "global" default now anyway, but a separate default per emulated card - current 4 for Cirrus, and 8 for stdvga & vmware. I suppose it would be possible to also add the ability to set cirrus down to 2 megs for cirrus too - pretty much everything is already in the code to emulate the 2 meg model anyway. All things considered, I consider it rather encouraging that no one has found anything other than memory defaults & limits to remark on so far. :) -- Trolle