Actually after trying to do lots of experiments and finally a git bisection, it turned out that the issue only affects qemu-kvm, not upstream qemu. Bisection between qemu-kvm 0.15.0 and 1.0 lead to this commit:
commit 145e11e840500e04a4d0a624918bb17596be19e9
Merge: ce967f6 b195043
Author: Avi Kivity <email address hidden>
Date: Wed Aug 10 12:06:58 2011 +0300
Merge commit 'b195043003d90ea4027ea01cc7a6c974ac915108' into upstream-merge
Actually after trying to do lots of experiments and finally a git bisection, it turned out that the issue only affects qemu-kvm, not upstream qemu. Bisection between qemu-kvm 0.15.0 and 1.0 lead to this commit:
commit 145e11e840500e0 4a4d0a624918bb1 7596be19e9
Merge: ce967f6 b195043
Author: Avi Kivity <email address hidden>
Date: Wed Aug 10 12:06:58 2011 +0300
Merge commit 'b195043003d90e a4027ea01cc7a6c 974ac915108' into upstream-merge
* commit 'b195043003d90e a4027ea01cc7a6c 974ac915108' : (130 commits)
...
After which I'm stuck... ;)