Jamie Lokier writes ("Re: [Xen-devel] Re: [Qemu-devel] [PATCH 01/13] Handle
terminating signals."):
Yes. Err, I'm not sure what effect that will have in Anthony's patch
but it probably wouldn't be good.
As I say I haven't managed to reproduce this other than in a full
qemu-dm tree (from qemu-xen).
So it may be that it is because of something I did or something the
qemu-xen code does - although it seems hard to imagine how it could
break the signal mask in the helper thread given that that thread runs
entirely glibc code, except when a signal is being delivered (and of
course the signal mask is saved and restored for signal delivery).