On Tue, Jun 4, 2013 at 1:26 AM, Dunrong Huang <riegama...@gmail.com> wrote:
> On Tue, Jun 4, 2013 at 3:51 PM, Gleb Natapov <g...@redhat.com> wrote:
>> On Tue, Jun 04, 2013 at 03:47:47PM +0800, Dunrong Huang wrote:
>> > On Tue, Jun 4, 2013 at 2:47 PM, Paolo Bonzini <pbonz...@redhat.com>
>> > wrote:
>> >
>> > > Il 04/06/2013 05:47, Dunrong Huang ha scritto:
>> > > >
>> > > > QEMU command:
>> > > > ~/usr/bin/qemu-system-x86_64 -enable-kvm -m 1024 debian-append.img
>> > > >
>> > > > git bisect tells that the following commit causes this bug:
>> > > >
>> > > > commit 235e8982ad393e5611cb892df54881c872eea9e1
>> > > > Author: Jordan Justen <jordan.l.jus...@intel.com
>> > > > <mailto:jordan.l.jus...@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.
>> > > >
>> > > > After reverting this commit, VM can boot normally.
>> > >
>> > > A patch is queued for that. Using kernel 3.8 or reverting the commit
>> > > will both work.
>> > >
>> > Ok, thanks for information, I will try it.
>> >
>> The fix is 651eb0f4 and you claim it is still fails for you. This is
>> strange because the commit fixed the problem for everyone else. Can you
>> double check that you are testing the right commit and you recompiled
>> and reinstalled?
>
>
> I am sure 651eb0f4 does not fix this problem.
>
> My test environment is below:
>
> * config.log:
> # head -n 2 config.log
> # QEMU configure log 2013年 06月 04日 星期二 16:12:59 CST
> # Configured with: './configure' '--prefix=/root/usr' '--enable-kvm'
> '--enable-werror' '--enable-debug' '--enable-debug-tcg'
> '--enable-debug-info' '--enable-sdl' '--enable-gtk' '--enable-virtfs'
> '--enable-vnc' '--enable-mixemu' '--enable-vnc-tls' '--enable-vnc-sasl'
> '--enable-vnc-jpeg' '--enable-vnc-png' '--enable-vnc-ws' '--enable-curses'
> '--enable-curl' '--enable-nptl' '--enable-system' '--enable-user'
> '--enable-linux-user' '--enable-guest-base' '--enable-uuid' '--enable-vde'
> '--enable-linux-aio' '--enable-cap-ng' '--enable-attr' '--enable-docs'
> '--enable-vhost-net' '--enable-spice' '--enable-usb-redir'
> '--enable-smartcard-nss' '--enable-tpm' '--enable-guest-agent'
> '--target-list=x86_64-softmmu'
>
> * kernel version:
> # uname -a
> Linux gentoo-company 3.8.2-gentoo #1 SMP Fri Mar 8 11:44:36 CST 2013 x86_64
> Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz GenuineIntel GNU/Linux
You were using a >3.8 kernel originally? (Someone mentioned trying a
3.8 kernel, and I think that is when you went to 3.8.)
> * details of git tree:
> # git log HEAD --oneline
> 1713924 gtk: don't use g_object_unref on GdkCursor
> 41686a9 gtk: don't resize window when enabling scaling
> 651eb0f fix double free the memslot in kvm_set_phys_mem
> 25b4833 configure: Report unknown target names more helpfully
> 6e92f82 configure: Autogenerate default target list
> 0ded1fe Merge remote-tracking branch 'pmaydell/arm-devs.next' into staging
> 95669e6 i.MX: Improve EPIT timer code.
> 6539ed2 exynos4210.c: register rom_mem for memory migration
>
>
> * QEMU command line:
> x86_64-softmmu/qemu-system-x86_64 -enable-kvm -cdrom
> /mnt/nfs/Images/ISO/ubuntu-12.04-dvd-amd64.iso
FWIW, I've been able to boot the 11.10 iso when booted to a 3.9 kernel.
Does it only fail after you boot the OS? If you just run KVM without a
disk, so only seabios runs, is it okay?
> After disable KVM_MEM_READONLY flag like below, VM can boot normally.
> diff --git a/kvm-all.c b/kvm-all.c
> index 405480e..c33ba6e 100644
> --- a/kvm-all.c
> +++ b/kvm-all.c
> @@ -774,7 +774,7 @@ static void kvm_set_phys_mem(MemoryRegionSection
> *section, bool add)
> mem->memory_size = size;
> mem->start_addr = start_addr;
> mem->ram = ram;
> - mem->flags = kvm_mem_flags(s, log_dirty, readonly_flag);
> + mem->flags = kvm_mem_flags(s, log_dirty, false);
>
> err = kvm_set_user_memory_region(s, mem);
> if (err) {
>
> I can provide more details if needed.
I don't think you mentioned how it fails. Does KVM crash? Is an error
message printed? Does the VM reset, or just hang?
-Jordan
