Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Mon, 22 May 2023 15:30:39 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Mike Christie <michael.christie@oracle.com>, linux@leemhuis.info,
        nicolas.dichtel@6wind.com, axboe@kernel.dk,
        torvalds@linux-foundation.org, linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, mst@redhat.com,
        sgarzare@redhat.com, jasowang@redhat.com, stefanha@redhat.com,
        brauner@kernel.org
Subject: Re: [RFC PATCH 1/8] signal: Dequeue SIGKILL even if
 SIGNAL_GROUP_EXIT/group_exec_task is set
Message-ID: <20230522133038.GB22159@redhat.com>
References: <20230518000920.191583-1-michael.christie@oracle.com>
 <20230518000920.191583-2-michael.christie@oracle.com>
 <87ednei9is.fsf@email.froward.int.ebiederm.org>
 <ab7d07ba-5dc3-95c0-aa7c-c2575d03f429@oracle.com>
 <20230518162508.GB20779@redhat.com>
 <05236dee-59b7-f394-db3d-cbb4d4163ce8@oracle.com>
 <20230518170359.GC20779@redhat.com>
 <875y8ph4tj.fsf@email.froward.int.ebiederm.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <875y8ph4tj.fsf@email.froward.int.ebiederm.org>
User-Agent: Mutt/1.5.24 (2015-08-30)
Precedence: bulk

On 05/18, Eric W. Biederman wrote:
>
>  void recalc_sigpending(void)
>  {
> -       if (!recalc_sigpending_tsk(current) && !freezing(current))
> +       if ((!recalc_sigpending_tsk(current) && !freezing(current)) ||
> +           ((current->signal->flags & SIGNAL_GROUP_EXIT) &&
> +                   !__fatal_signal_pending(current)))
>                 clear_thread_flag(TIF_SIGPENDING);
>  
>  }
> @@ -1043,6 +1045,13 @@ static void complete_signal(int sig, struct task_struct *p, enum pid_type type)
>                  * This signal will be fatal to the whole group.
>                  */
>                 if (!sig_kernel_coredump(sig)) {
> +                       /*
> +                        * The signal is being short circuit delivered
> +                        * don't it pending.
> +                        */
> +                       if (type != PIDTYPE_PID) {
> +                               sigdelset(&t->signal->shared_pending,  sig);
> +
>                         /*
>                          * Start a group exit and wake everybody up.
>                          * This way we don't have other threads

Eric, sorry. I fail to understand this patch.

How can it help? And whom?

Perhaps we can discuss it in the context of the new series from Mike?

Oleg.