Re: [Qemu-devel] [PATCHv3] report that QEMU process was killed by a signal

[Gleb Natapov <gleb@redhat.com>]

On Wed, Mar 30, 2011 at 07:39:31PM +0100, Peter Maydell wrote:
> On 15 March 2011 11:56, Gleb Natapov <gleb@redhat.com> wrote:
> > Currently when rogue script kills QEMU process (using TERM/INT/HUP
> > signal) it looks indistinguishable from system shutdown. Lets report
> > that QEMU was killed and leave some clues about the killer identity.
> 
> Unfortunately this patch causes qemu to segfault when killed
> via ^C (at least on my Ubuntu maverick system). This is because
> it registers a signal handler with sigaction, but then later
> the SDL library is initialised and it reinstalls our handler
> with plain old signal:
> 
>         ohandler = signal(SIGINT, SDL_HandleSIG);
>         if ( ohandler != SIG_DFL )
>                 signal(SIGINT, ohandler);
> 
I fixed this in SDL upstream.

> This is clearly buggy but on the other hand SDL is pretty widely
> deployed and it's the default QEMU video output method, so I think
> we need to work around it :-(
> 
> The most straightforward fix is to get the signal number from
> argument one and not to bother printing the PID that killed us.
> 
For debugging purposes pid is useful. We cam register signal handler
after SDL is initialized though (if waiting for SDL update is not an
option).

--
			Gleb.