From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:44177)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <lekensteyn@gmail.com>) id 1UjZ5N-0003Id-5W
	for qemu-devel@nongnu.org; Mon, 03 Jun 2013 14:02:30 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <lekensteyn@gmail.com>) id 1UjZ5J-00052G-0A
	for qemu-devel@nongnu.org; Mon, 03 Jun 2013 14:02:25 -0400
Received: from mail-bk0-x230.google.com ([2a00:1450:4008:c01::230]:65071)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <lekensteyn@gmail.com>) id 1UjZ5I-000521-P7
	for qemu-devel@nongnu.org; Mon, 03 Jun 2013 14:02:20 -0400
Received: by mail-bk0-f48.google.com with SMTP id jf20so2137742bkc.35
	for <qemu-devel@nongnu.org>; Mon, 03 Jun 2013 11:02:19 -0700 (PDT)
From: Peter Wu <lekensteyn@gmail.com>
Date: Mon, 03 Jun 2013 20:02:16 +0200
Message-ID: <1650244.ohnSj2ZDUA@al>
In-Reply-To: <CAFe8ug-P3D8rJKoduPt_=oojZ823Rg55nNbQ+pcXT8GhtHz1gQ@mail.gmail.com>
References: <11353237.fLVsHzmD7c@al>
	<CAFe8ug-P3D8rJKoduPt_=oojZ823Rg55nNbQ+pcXT8GhtHz1gQ@mail.gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 7Bit
Content-Type: text/plain; charset="us-ascii"
Subject: Re: [Qemu-devel] QEMU aborts since "kvm: support using
	KVM_MEM_READONLY flag for regions"
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Jordan Justen <jljusten@gmail.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>, Anthony Liguori <aliguori@us.ibm.com>, Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>, qemu-devel <qemu-devel@nongnu.org>, Paolo Bonzini <pbonzini@redhat.com>

On Monday 03 June 2013 10:35:28 Jordan Justen wrote:
> This should be fixed by Xiao's "fix double free the memslot in
> kvm_set_phys_mem" patch.
Confirmed, with this one-liner patch the bug is gone.

> On Mon, Jun 3, 2013 at 10:23 AM, Peter Wu <lekensteyn@gmail.com> wrote:
> > Hi,
> > 
> > With the current git source (f10acc8b38d65a66ffa0588a036489d7fa6a593e),
> > 
> > `qemu-system-x86_64 -enable-kvm` fails to run with the following error:
> >     kvm_set_phys_mem: error unregistering overlapping slot: Invalid
> >     argument
> > 
> > After this message, qemu aborts. Reverting the following commit on top of
> > master makes the bug go away. Removing the `-enable-kvm` option also
> > allows QEMU to operate, but without KVM.
> > 
> > commit 235e8982ad393e5611cb892df54881c872eea9e1
> > Author: Jordan Justen <jordan.l.justen@intel.com>
> > Date:   Wed May 29 01:27:26 2013 -0700
> > 
> >     kvm: support using KVM_MEM_READONLY flag for regions
> >     
> >     For readonly memory regions and rom devices in romd_mode,
> >     we make use of the KVM_MEM_READONLY. A slot that uses
> >     KVM_MEM_READONLY can be read from and code can execute from the
> >     region, but writes will exit to qemu.
> >     
> >     For rom devices with !romd_mode, we force the slot to be
> >     removed so reads or writes to the region will exit to qemu.
> >     (Note that a memory region in this state is not executable
> >     within kvm.)
> > 
> > QEMU was built using GCC 4.8.0, runs on Arch Linux 64-bit with a
> > custom kernel, Linux 3.9.1. CPU: i5-460M. A backtrace is provided
> > on the bottom of this message. If you need more details, please ask.
> > 
> > Regards,
> > Peter
> > 
> > #0  0x00007ffff1a251c9 in raise () from /usr/lib/libc.so.6
> > #1  0x00007ffff1a265c8 in abort () from /usr/lib/libc.so.6
> > #2  0x00005555557dd84d in kvm_set_phys_mem (section=0x7fffe6fdca00,
> > add=false) at /tmp/qemu/kvm-all.c:715 #3  0x00005555557e132c in
> > address_space_update_topology_pass (as=as@entry=0x5555564dae00
> > <address_space_memory>, adding=adding@entry=false, old_view=...,
> > new_view=...) at /tmp/qemu/memory.c:725 #4  0x00005555557e1f13 in
> > address_space_update_topology (as=0x5555564dae00 <address_space_memory>)
> > at /tmp/qemu/memory.c:761 #5  memory_region_transaction_commit () at
> > /tmp/qemu/memory.c:786
> > #6  0x00005555557dfa42 in access_with_adjusted_size (addr=addr@entry=2,
> > value=value@entry=0x7fffe6fdcc18, size=1, access_size_min=<optimized
> > out>, access_size_max=<optimized out>,> 
> >     access=access@entry=0x5555557e0000 <memory_region_write_accessor>,
> >     opaque=opaque@entry=0x55555658c238) at /tmp/qemu/memory.c:399> 
> > #7  0x00005555557e0f77 in memory_region_iorange_write (iorange=<optimized
> > out>, offset=2, width=1, data=51) at /tmp/qemu/memory.c:475 #8 
> > 0x00005555557de562 in kvm_handle_io (count=1, size=1, direction=1,
> > data=<optimized out>, port=3326) at /tmp/qemu/kvm-all.c:1507 #9 
> > kvm_cpu_exec (env=env@entry=0x55555656f750) at /tmp/qemu/kvm-all.c:1659
> > #10 0x000055555578da05 in qemu_kvm_cpu_thread_fn (arg=0x55555656f750) at
> > /tmp/qemu/cpus.c:759 #11 0x00007ffff6280dd2 in start_thread () from
> > /usr/lib/libpthread.so.0 #12 0x00007ffff1ad5cdd in clone () from
> > /usr/lib/libc.so.6