Re: [Qemu-devel] qemu-kvm: remove "boot=on|off" drive parameter compatibility

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2012-10-04 19:21, Lucas Meneghel Rodrigues wrote:
> On 10/04/2012 09:27 AM, Jan Kiszka wrote:
>> On 2012-10-04 14:10, Lucas Meneghel Rodrigues wrote:
>>> On 10/04/2012 07:48 AM, Jan Kiszka wrote:
>>>> On 2012-10-03 15:19, Paolo Bonzini wrote:
>>>>> Il 03/10/2012 12:57, Lucas Meneghel Rodrigues ha scritto:
>>>>>> Yep, I did send patches with the testdev device present on qemu-kvm.git
>>>>>> to qemu.git a while ago, but there were many comments on the review, I
>>>>>> ended up not implementing everything that was asked and the patches were
>>>>>> archived.
>>>>>>
>>>>>> If nobody wants to step up to port it, I'll re-read the original thread
>>>>>> and will spin up new patches (and try to go through the end with it).
>>>>>> Executing the KVM unittests is something that we can't afford to lose,
>>>>>> so I'd say it's important on this last mile effort to get rid of qemu-kvm.
>>>>>
>>>>> Absolutely, IIRC the problem was that testdev did a little bit of
>>>>> everything... let's see what's the functionality of testdev:
>>>>>
>>>>> - write (port 0xf1), can be replaced in autotest with:
>>>>> -device isa-debugcon,iobase=0xf1,chardev=...
>>>>>
>>>>> - exit code (port 0xf4), see this series:
>>>>> http://lists.gnu.org/archive/html/qemu-devel/2012-07/msg00818.html
>>>>>
>>>>> - ram size (port 0xd1).  If we can also patch kvm-unittests, the memory
>>>>> is available in the CMOS or in fwcfg.  Here is the SeaBIOS code:
>>>>>
>>>>>           u32 rs = ((inb_cmos(0x34) << 16) | (inb_cmos(0x35) << 24));
>>>>>           if (rs)
>>>>>               rs += 16 * 1024 * 1024;
>>>>>           else
>>>>>               rs = (((inb_cmos(0x30) << 10) | (inb_cmos(0x31) << 18))
>>>>>                     + 1 * 1024 * 1024);
>>>>>
>>>>> The rest (ports 0xe0..0xe7, 0x2000..0x2017, MMIO) can be left in testdev.
>>>>
>>>> IIRC, one of the biggest problem with testdev was its hack to inject
>>>> interrupts.
>>>
>>> Jan, I assume this commit helps to fix this, right?
>>>
>>> commit b334ec567f1de9a60349991e7b75083d569ddb0a
>>> Author: Jan Kiszka <jan.kiszka@siemens.com>
>>> Date:   Fri Mar 2 10:30:47 2012 +0100
>>>
>>>       qemu-kvm: Use upstream kvm-i8259
>>>
>>>       Drop the qemu-kvm version in favor of the equivalent upstream
>>>       implementation. This allows to move the i8259 back into the hwlib.
>>>
>>>       Note that this also drops the testdev hack and restores proper
>>>       isa_get_irq. If testdev scripts exist that inject > IRQ15, they need
>>>       fixing. Testing for these interrupts on the PIIX3 makes no practical
>>>       sense anyway as those lines are unused.
>>>
>>>       Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>>>       Signed-off-by: Avi Kivity <avi@redhat.com>
>>
>> Yes, this improved it a lot as we no longer depend on additional
>> changes. I'm not sure if there was resistance beyond that.
>>
>> When cleaning up the code: register_ioport_read must be replaced with
>> the memory API.
> 
> I did look at the MemoryRegionOps/memory_region_init_io and still did 
> not figure out how to port things. I'll send a v2 addressing all the 
> comments made so far but this one, just to see if people are OK with the 
> direction of the full patch, then if you could give me some pointers of 
> how to do this conversion, it'd be great.
> 

See e.g. http://thread.gmane.org/gmane.comp.emulators.qemu/171217

Jan

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