Re: [Qemu-devel] [edk2] OVMF hung on qemu 1.6.0 with KVM

[Gary Ching-Pang Lin]

On Wed, Aug 28, 2013 at 02:55:26PM +0200, Andreas Färber wrote:
> Am 28.08.2013 14:10, schrieb Laszlo Ersek:
> > On 08/28/13 13:49, Andreas Färber wrote:
> >> Am 28.08.2013 13:45, schrieb Laszlo Ersek:
> >>> (qemu-devel CC'd)
> >>>
> >>> On 08/28/13 12:35, Gary Ching-Pang Lin wrote:
> >>>> Hi,
> >>>>
> >>>> I recently updated qemu to 1.6.0 and found OVMF just showed a blank
> >>>> screen when kvm was enabled. I tried to dump OVMF log with the
> >>>> following commond but nothing was stored in debug.log.
> >>>>
> >>>> qemu-system-x86_64 -s -enable-kvm -bios OVMF.fd -debugcon file:debug.log 
> >>>> -global isa-debugcon.iobase=0x402
> >>>>
> >>>> The kvm trace was recorded with "trace-cmd record -b 20000 -e kvm"
> >>>> and uploaded to the following link:
> >>>> https://docs.google.com/file/d/0B9hbtlc_aK_gcGh2TDZLUVlzWWc/edit?usp=sharing
> >>>>
> >>>> I found a similar case with kernel < 3.9, but I already upgraded linux
> >>>> kernel to 3.10.5, so this may be another bug.
> >>>
> >>> Well, the usual first response in cases like this is...
> >>>
> >>> Can you bisect qemu? :)
> >>
> >> We had a similar report:
> >> https://bugzilla.novell.com/show_bug.cgi?id=835895
> > 
> > Well that's sorta the same report, considering you and Gary both work
> > for SUSE, and the Novell BZ seems to imply the build in question was Gary's:
> > 
> >> qemu 1.6.0 fails to run the tianocore firmware
> >> (home:gary_lin:UEFI/OVMF) properly. This worked with previous qemu
> >         ^^^^^^^^
> >> versions:
> > 
> > :)
> 
> Different reporters, so who knows if the setups are the same. ;)
> 
> >> git-bisect said:
> >> 235e8982ad393e5611cb892df54881c872eea9e1 is the first bad commit
> >> commit 235e8982ad393e5611cb892df54881c872eea9e1
> >> Author: Jordan Justen <address@hidden>
> >> 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.)
> >>
> >>     v7:
> >>      * Update for readable => romd_mode rename (5f9a5ea1)
> >>
> >>     Signed-off-by: Jordan Justen <address@hidden>
> >>     Reviewed-by: Xiao Guangrong <address@hidden> (v4)
> >>     Reviewed-by: Paolo Bonzini <address@hidden> (v5)
> >>     Message-id: address@hidden
> >>     Signed-off-by: Anthony Liguori <address@hidden>
> >>
> >>
> >> Any hints or patches welcome. :)
> > 
> > Hm. LP 1212402 <https://bugs.launchpad.net/qemu/+bug/1212402> probably
> > concerns the "similar case with kernel < 3.9" mentioned by Gary, and is
> > likely not revelant here.
> > 
> > 
> > Gary & Ludwig, can you confirm that your OVMF build includes SVN r14494?
> > 
> > Author: Jordan Justen <address@hidden>
> > Date:   Thu Jul 18 22:51:27 2013 +0000
> > 
> >     OvmfPkg/Sec: Build identity mapped pages in RAM for X64
> > 
> >     This is based on MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c.
> > 
> >     Previously we would run using page tables built into the
> >     firmware device.
> > 
> >     If a flash memory is available, it is unsafe for the page
> >     tables to be stored in memory since the processor may try
> >     to write to the page table data structures.
> > 
> >     Additionally, when KVM ROM support is enabled for the
> >     firmware device, then PEI fails to boot when the page
> >     tables are in the firmware device.
> 
> https://build.opensuse.org/package/show/Virtualization/OVMF
> is at r14547 and that one works for me.
> 
> Gary/Ludwig, can you confirm that this is resolved?
>
I still got the black screen even with OVMF r14547 or r14608. I also
tried kernel 3.10.9 and 3.11-rc7, but no luck.

Reverting the KVM_MEM_READONLY patch works for me, but the OVMF patch
somehow didn't work.

Thanks,

Gary Lin