Re: [PATCH v7 00/15] x86/hvm: I/O emulation cleanup and fix | Full Backtrace of domU's X crash caused by SSE2 istruction in attachment

[Fabio Fantoni <fabio.fantoni@m2r.biz>]

Il 10/07/2015 13:00, Jan Beulich ha scritto:
>>>> On 10.07.15 at 12:51, <fabio.fantoni@m2r.biz> wrote:
>> Il 10/07/2015 12:20, Jan Beulich ha scritto:
>>> Other than MOVD, MOVAPS is already being supported by the
>>> insn emulator.
>>>
>> Then why do you think MOVAPS fails in my test?
> No idea. That's what Paul asked you to narrow down.
Can you be more specific about instrumenting xen because I don't know 
what to do, other then using gdb on domU xorg. Any hint would be 
appreciated.
>> Sse2 was introduced in cpus 11 years ago, so I think it would be useful
>> to add support for all missing instructions to avoid more cases like
>> this (and it seems to improve performance too, comparing the same task
>> executed with/without sse2).
> The reason we didn't add any more of the SSE insns so far is that
> we don't expect them to be used for accessing MMIO. Once we
> learn they're needed, we'll add emulation for them, but you
> realize this is a significant task?
>
> Jan
>
Sorry for this, since the end of 2011 I'm trying desperately to improve 
recent desktop domUs graphic performance (windows >xp), recent linux DE 
(gnome 3, unity ecc...), bigger resolutions (7-8 years ago the standard 
was 1024x768 now it's around 1920x1080)
FWIK this seems necessary for what I'm trying to achieve (and to anyone 
other who want to do the same since I post all my patches), it seems 
also needed for xengt (in development) and there may be others.

A temp. solution at least to have qxl fully working on any linux domUs 
can be to find the workaround/fix that make it work in SUSE and apply it 
upstream....
 From my mail of some days ago:
> I also took a fast look at suse kernel patches 
> (https://github.com/openSUSE/kernel-source/tree/SLE12-SP1) where qxl 
> is also working on linux domUs (other things seems already similar 
> based on what Jim Fehlig told me) but I didn't find a possible 
> fix/workaround for it to try. Can someone tell me about possible 
> patches I should try please?

Thanks for any reply.