[Qemu-devel] FPU x86 instructions error

[Clemens Kolbitsch]

Hi guys,

we recently had an issue with running a program using FPU instructions
to obtain the current EIP (basically a weird way of "call 0; pop eax")
that was not working on QEMU (with TCG).

Looking at the problem, we found this patch to be useful/fixing the issue:

https://launchpadlibrarian.net/140457932/patch-qemu-1.5.0-fpip.diff

Looking through the DEVEL archives, I found this patch

http://lists.nongnu.org/archive/html/qemu-devel/2011-06/msg01206.html

that adds the FPU flags to the environment, but is only using them for KVM.

I was wondering - since the above patch is rather old, you have
probably come across it before - if there was a reason for not
including it in QEMU (I checked in git:master and it's not applied).
If there isn't, maybe it'd be worth re-considering :)

thanks!
-Clemens


--
Clemens Kolbitsch
Security Researcher
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Lastline, Inc.
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