Re: [Qemu-devel] [PATCHv2] report that QEMU process was killed by a signal

[Blue Swirl <blauwirbel@gmail.com>]

On Mon, Mar 14, 2011 at 3:44 PM, 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 QMEU was killed and leave some clues about the killed identity.

QEMU ;-)

>
> Signed-off-by: Gleb Natapov <gleb@redhat.com>
> ---
>  v1->v2:
>  - print message from a main loop instead of signal handler
>
> diff --git a/os-posix.c b/os-posix.c
> index 38c29d1..36d937c 100644
> --- a/os-posix.c
> +++ b/os-posix.c
> @@ -61,9 +61,9 @@ void os_setup_early_signal_handling(void)
>     sigaction(SIGPIPE, &act, NULL);
>  }
>
> -static void termsig_handler(int signal)
> +static void termsig_handler(int signal, siginfo_t *info, void *c)
>  {
> -    qemu_system_shutdown_request();
> +    qemu_system_killed(info->si_signo, info->si_pid);
>  }
>
>  static void sigchld_handler(int signal)
> @@ -76,7 +76,8 @@ void os_setup_signal_handling(void)
>     struct sigaction act;
>
>     memset(&act, 0, sizeof(act));
> -    act.sa_handler = termsig_handler;
> +    act.sa_sigaction = termsig_handler;
> +    act.sa_flags = SA_SIGINFO;
>     sigaction(SIGINT,  &act, NULL);
>     sigaction(SIGHUP,  &act, NULL);
>     sigaction(SIGTERM, &act, NULL);
> diff --git a/sysemu.h b/sysemu.h
> index 0a83ab9..fc7048a 100644
> --- a/sysemu.h
> +++ b/sysemu.h
> @@ -66,6 +66,8 @@ void qemu_system_vmstop_request(int reason);
>  int qemu_shutdown_requested(void);
>  int qemu_reset_requested(void);
>  int qemu_powerdown_requested(void);
> +void qemu_system_killed(int signal, int pid);

pid_t pid

> +void qemu_kill_report(void);
>  extern qemu_irq qemu_system_powerdown;
>  void qemu_system_reset(void);
>
> diff --git a/vl.c b/vl.c
> index 5e007a7..d14c42d 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -1213,7 +1213,7 @@ typedef struct QEMUResetEntry {
>  static QTAILQ_HEAD(reset_handlers, QEMUResetEntry) reset_handlers =
>     QTAILQ_HEAD_INITIALIZER(reset_handlers);
>  static int reset_requested;
> -static int shutdown_requested;
> +static int shutdown_requested, shutdown_signal = -1, shutdown_pid;

static pid_t shutdown_pid;

>  static int powerdown_requested;
>  static int debug_requested;
>  static int vmstop_requested;
> @@ -1225,6 +1225,15 @@ int qemu_shutdown_requested(void)
>     return r;
>  }
>
> +void qemu_kill_report(void)
> +{
> +    if (shutdown_signal != -1) {
> +        fprintf(stderr, "Got signal %d from pid %d\n",

Are there any systems with 64 bit pid_t? Then a cast may be needed
and/or format adjusted.

> +                         shutdown_signal, shutdown_pid);
> +        shutdown_signal = -1;
> +    }
> +}
> +
>  int qemu_reset_requested(void)
>  {
>     int r = reset_requested;
> @@ -1298,6 +1307,13 @@ void qemu_system_reset_request(void)
>     qemu_notify_event();
>  }
>
> +void qemu_system_killed(int signal, int pid)

pid_t pid