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

["Andreas Färber" <afaerber@suse.de>]

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 <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.)
>>
>>     v7:
>>      * Update for readable => romd_mode rename (5f9a5ea1)
>>
>>     Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
>>     Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> (v4)
>>     Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> (v5)
>>     Message-id: 1369816047-16384-4-git-send-email-jordan.l.justen@intel.com
>>     Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
>>
>>
>> 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 <jordan.l.justen@intel.com>
> 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?

Thanks,
Andreas

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