Re: [Qemu-devel] audit needed for signal handlers

[Gerd Hoffmann]

On Mo, 2013-11-11 at 18:47 +0100, Paolo Bonzini wrote:
> Il 11/11/2013 18:13, Peter Maydell ha scritto:
> >> > That said, aren't all signals in QEMU (except SIG_IPI) caught with
> >> > signalfd and the handlers run synchronously in the iothread?
> > Eric specifically points out one which is not.
> > (I'm pretty sure that 'reinstall signal handler at
> > end of signal handler' is ancient voodoo that we don't
> > want either, incidentally.)
> 
> Yeah, I was convinced it was---I still cannot find a reason why SIGWINCH
> needs to be handled synchronously.

There is zero need.  And changing that is actually the correct fix IMHO:
Just set a flag in the signal handler (i.e. no syscalls which then could
corrupt errno), then handle it the next time we update the screen.

cheers,
  Gerd