From mboxrd@z Thu Jan  1 00:00:00 1970
From: Harald Braumann <harry@unheit.net>
Subject: Single-stepping real-mode does not work
Date: Sat, 14 Jul 2012 12:52:47 +0200
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(please CC, since I'm not subscribed)

Hi,

trying to debug some BIOS code, but single-stepping through real-mode
doesn't work. It always continues, instead of breaking after the next
instruction. 

So I wanted to know, if there are known issues, or if this is supposed
to work.

CPU: AMD FX
QEMU: latest from git://git.kernel.org/pub/scm/virt/kvm/qemu-kvm.git
Linux: latest from
  git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

I start QEMU with `qemu-system-x86_64 -S -s', connect gdb and use the
`stepi' command. But instead of executing one instruction and
breaking, it just continues the programme. 

If I start QEMU with `-no-kvm', it works. So the problem seems to be
in the kvm module.

Cheers,
harry