Re: [Qemu-devel] Bug report - Windows XP guest failure

[Michael Tokarev <mjt@tls.msk.ru>]

07.05.2015 09:12, Michael Tokarev wrote:
> 07.05.2015 04:11, G 3 wrote:
>> Did you boot Windows XP to the desktop? I have tested Windows 95, Windows 2000, and Windows XP. All of them fail to boot to the desktop.
> 
> Yes, booted to desktop and did some minimal work in there,
> installnig one update or two.
> 
>> Command used:
>> ./i386-softmmu/qemu-system-i386 -boot c -hda "Windows XP Hard Drive.img" 
> 
> Aha. You run without kvm, in tcg mode.  I don't usually do that,
> lemme try...

Ok, I can reproduce this, winXP BSODs on boot in tcg mode.
Git bisect points to this:

commit 23820dbfc79d1c9dce090b4c555994f2bb6a69b3
Author: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Date:   Mon Mar 16 22:35:54 2015 -0700

    exec: Respect as_translate_internal length clamp

    address_space_translate_internal will clamp the *plen length argument
    based on the size of the memory region being queried. The iommu walker
    logic in addresss_space_translate was ignoring this by discarding the
    post fn call value of *plen. Fix by just always using *plen as the
    length argument throughout the fn, removing the len local variable.

    This fixes a bootloader bug when a single elf section spans multiple
    QEMU memory regions.

    Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
    Message-Id: <1426570554-15940-1-git-send-email-peter.crosthwaite@xilinx.com>
    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Cc'ing relevant people.

/mjt