From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39864) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bNfwq-0006pT-EU for qemu-devel@nongnu.org; Thu, 14 Jul 2016 08:41:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bNfwm-0004fI-CX for qemu-devel@nongnu.org; Thu, 14 Jul 2016 08:40:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52930) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bNfwm-0004fE-6d for qemu-devel@nongnu.org; Thu, 14 Jul 2016 08:40:56 -0400 References: <1467650742-17580-1-git-send-email-mst@redhat.com> <20160704194615-mutt-send-email-mst@redhat.com> <20160711144257.GA29623@hhmipssw201.hh.imgtec.org> <5783B8D5.9050309@redhat.com> <819ccefc-b0d7-527b-164a-6774f96b8ac5@ilande.co.uk> From: Marcel Apfelbaum Message-ID: <5787884E.9080702@redhat.com> Date: Thu, 14 Jul 2016 15:40:46 +0300 MIME-Version: 1.0 In-Reply-To: <819ccefc-b0d7-527b-164a-6774f96b8ac5@ilande.co.uk> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PULL 03/36] hw/pci: delay bus_master_enable_region initialization List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Mark Cave-Ayland , Leon Alrae , "Michael S. Tsirkin" Cc: Peter Maydell , qemu-devel@nongnu.org, Paolo Bonzini On 07/11/2016 09:41 PM, Mark Cave-Ayland wrote: > On 11/07/16 16:18, Marcel Apfelbaum wrote: > >> On 07/11/2016 05:42 PM, Leon Alrae wrote: >>> Hi, >>> >>> This commit causes regressions in my MIPS tests. QEMU segfaults when >>> booting Linux on Malta board; >> >> Hi Leon, >> >> Is a good thing you caught it in the pull request, thanks! >> Is a pity we don't have a way to run sanity tests on all archs (beyond >> make check) >> >> this can be easily reproduced with >>> Aurelien's Debian images: >>> >>> wget >>> https://people.debian.org/~aurel32/qemu/mipsel/vmlinux-3.2.0-4-5kc-malta >>> wget >>> https://people.debian.org/~aurel32/qemu/mipsel/debian_wheezy_mipsel_standard.qcow2 >>> >>> qemu-system-mips64el -M malta -kernel vmlinux-3.2.0-4-5kc-malta -hda >>> debian_wheezy_mipsel_standard.qcow2 -append "root=/dev/sda1 >>> console=ttyS0" -nographic >>> >> >> I'll reproduce and handle it, thanks! >> Marcel > > FWIW this looks like the exact same backtrace I reported with > qemu-system-sparc64 so hopefully the solution should fix both problems :) > Hi Mark and Leon, I've reproduced both failures and I've found the root cause. The PCI root bus is not realized as part of the machine initialization. Until now the only consequence was the machine couldn't be migrated (because the vmstate is initialized as part of 'realize'). However, from now on the devices cannot do DMA requests if the bus is not 'realized'. It took some time because I had to go over all the archs and check this issue. I have the patches ready, I am running some more tests and post them soon. Thanks for the patience, Marcel > > ATB, > > Mark. >