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Biederman" , Tycho Andersen , linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] pidfd: change pidfd_send_signal() to respect PIDFD_THREAD Message-ID: <20240208161118.GI19801@redhat.com> References: <20240207114549.GA12697@redhat.com> <20240208-fragt-prospekt-7866333b15f0@brauner> <20240208135344.GD19801@redhat.com> <20240208143407.GF19801@redhat.com> <20240208-klopapier-aushebeln-446ac80a6e9b@brauner> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240208-klopapier-aushebeln-446ac80a6e9b@brauner> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 On 02/08, Christian Brauner wrote: > > > Is prepare_kill_siginfo() correct when we send a signal to the child > > pid namespace? si_pid = task_tgid_vnr(current) doesn't look right in > > this case but perhaps I am totally confused. > > > > And why do we need it at all? Can't sys_kill() and pidfd_send_signal() > > just use SEND_SIG_NOINFO? > > Yeah, good point. I don't remember as it's been quite a while ago. My > guess is that it just tried to mirror kill() itself without being aware > of SEND_SIG_NOINFO. If you don't find anything wrong with this then > switch it to SEND_SIG_NOINFO in a preparatory patch we can backport, > please. Yes, but I still feel I must have missed something. Will read this code tomorrow. And another note for the record before I forget this. We can probably improve and rename access_pidfd_pidns(). Currently it is only used by pidfd_send_signal() but pidns_install() looks like another user. Oleg.