From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35180) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WBmU6-0002JV-Ip for qemu-devel@nongnu.org; Fri, 07 Feb 2014 09:32:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WBmU1-0007Q7-Rs for qemu-devel@nongnu.org; Fri, 07 Feb 2014 09:32:50 -0500 Message-ID: <52F4EE0E.8080906@ilande.co.uk> Date: Fri, 07 Feb 2014 14:30:38 +0000 From: Mark Cave-Ayland MIME-Version: 1.0 References: <1391730002-18073-1-git-send-email-pbonzini@redhat.com> In-Reply-To: <1391730002-18073-1-git-send-email-pbonzini@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] memory: fix limiting of translation at a page boundary List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Anthony Perard , Stefano Stabellini , qemu-devel@nongnu.org, qemu-stable@nongnu.org On 06/02/14 23:40, Paolo Bonzini wrote: > Commit 360e607 (address_space_translate: do not cross page boundaries, > 2014-01-30) broke MMIO accesses in cases where the section is shorter > than the full register width. This can happen for example with the > Bochs DISPI registers, which are 16 bits wide but have only a 1-byte > long MemoryRegion (if you write to the "second byte" of the register > your access is discarded; it doesn't write only to half of the register). > > Restrict the action of commit 360e607 to direct RAM accesses. This > is enough for Xen, since MMIO will not go through the mapcache. > > Reported-by: Mark Cave-Ayland > Tested-by: Anthony Perard > Cc: qemu-stable@nongnu.org > Signed-off-by: Paolo Bonzini Hi Paolo, Unfortunately I've just tested this patch on qemu-system-ppc and it still doesn't fix the issue for me :( This is with current git master bc1c7 plus your patch applied. The symptoms haven't changed in that the VGA output stays black and doesn't resize, again implying that the VGA VBE calls aren't working. If it helps, the OpenBIOS VGA driver vga.fs can be found at http://git.qemu.org/?p=openbios.git;a=blob;f=drivers/vga.fs;h=ec4c6c5f10ea2c4c784c3c6888c3805ec3b14496;hb=888126272f92294b0da45158393f1b862742cf6b. ATB, Mark.