Re: [Qemu-devel] User emulation & gdb & sigsegv

["Edgar E. Iglesias" <edgar.iglesias@axis.com>]

On Thu, Dec 11, 2008 at 12:06:53AM +0100, Lionel Landwerlin wrote:
> Hello,
> 
> Currently, when using gdb connected to qemu, if a sigsegv is raised,
> Qemu just exits.
> 
> How should I modify Qemu to redirect this last signal to the connected
> gdb and print a stack trace at least ?
> 
> I tried to call gdb_handlesig(gdbstub.c) from
> force_sig(linux-user/signal.c) but Qemu just crashes.
> 
> Any idea is welcome :)

Hello,

I've got this in my git, IIRC it helped me out in those situations.

Cheers

commit 1efa40a743e16dbe2803a8d16902bf89850e80a3
Author: Edgar E. Iglesias <edgar.iglesias@axis.com>
Date:   Mon Sep 29 14:14:24 2008 +0200

    Pass default handler signals to gdb aswell.

diff --git a/linux-user/signal.c b/linux-user/signal.c
index 9640923..b7d22a1 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -365,6 +365,7 @@ int queue_signal(CPUState *env, int sig, target_siginfo_t *info)
         if (sig != TARGET_SIGCHLD &&
             sig != TARGET_SIGURG &&
             sig != TARGET_SIGWINCH) {
+	    sig = gdb_handlesig(env, sig);
             force_sig(sig);
         } else {
             return 0; /* indicate ignored */