Re: [PATCH v3 4/7] linux/signal.h: Ignore SIGINFO by default in new tasks

[Jiri Slaby <jslaby@suse.cz>]

On 30. 04. 20, 8:42, Arseny Maslennikov wrote:
> This matches the behaviour of other Unix-like systems that have SIGINFO
> and causes less harm to processes that do not install handlers for this
> signal, making the keyboard status character non-fatal for them.
> 
> This is implemented with the assumption that SIGINFO is defined
> to be equivalent to SIGPWR; still, there is no reason for PWR to
> result in termination of the signal recipient anyway — it does not
> indicate there is a fatal problem with the recipient's execution
> context (like e.g. FPE/ILL do), and we have TERM/KILL for explicit
> termination requests.
> 
> To put it another way:
> The only scenario where system behaviour actually changes is when the
> signal recipient has default disposition for SIGPWR. If a process
> chose to interpret a SIGPWR as an incentive to cleanly terminate, it
> would supply its own handler — and this commit does not affect processes
> with non-default handlers.
> 
> Signed-off-by: Arseny Maslennikov <ar@cs.msu.ru>
> ---
>  include/linux/signal.h | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/signal.h b/include/linux/signal.h
> index 05bacd2ab..dc31da8fc 100644
> --- a/include/linux/signal.h
> +++ b/include/linux/signal.h
> @@ -369,7 +369,7 @@ extern bool unhandled_signal(struct task_struct *tsk, int sig);
>   *	|  SIGSYS/SIGUNUSED  |	coredump 	|
>   *	|  SIGSTKFLT         |	terminate	|
>   *	|  SIGWINCH          |	ignore   	|
> - *	|  SIGPWR            |	terminate	|
> + *	|  SIGPWR            |	ignore   	|

You need to update signal.7 too:
https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/man7/signal.7#n285

thanks,
-- 
js
suse labs