From: Oleg Nesterov <oleg@redhat.com>
To: Christian Brauner <christian.brauner@ubuntu.com>
Cc: linux-kernel@vger.kernel.org, Florian Weimer <fweimer@redhat.com>,
Arnd Bergmann <arnd@arndb.de>,
libc-alpha@sourceware.org, David Howells <dhowells@redhat.com>,
Jann Horn <jannh@google.com>, Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
Shuah Khan <shuah@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Michal Hocko <mhocko@suse.com>,
Elena Reshetova <elena.reshetova@intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Roman Gushchin <guro@fb.com>,
Andrea Arcangeli <aarcange@redhat.com>Al Viro <v>
Subject: Re: [PATCH v3 1/2] clone3: add CLONE_CLEAR_SIGHAND
Date: Mon, 21 Oct 2019 16:46:33 +0200 [thread overview]
Message-ID: <20191021144633.GA2720@redhat.com> (raw)
In-Reply-To: <20191014104538.3096-1-christian.brauner@ubuntu.com>
On 10/14, Christian Brauner wrote:
>
> The child helper process on Linux posix_spawn must ensure that no signal
> handlers are enabled, so the signal disposition must be either SIG_DFL
> or SIG_IGN. However, it requires a sigprocmask to obtain the current
> signal mask and at least _NSIG sigaction calls to reset the signal
> handlers for each posix_spawn call
Plus the caller has to block/unblock all signals around clone(VM|VFORK).
Can this justify the new CLONE_ flag? Honestly, I have no idea. But the
patch is simple and looks technically correct to me. FWIW,
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
WARNING: multiple messages have this Message-ID (diff)
From: Oleg Nesterov <oleg@redhat.com>
To: Christian Brauner <christian.brauner@ubuntu.com>
Cc: linux-kernel@vger.kernel.org, Florian Weimer <fweimer@redhat.com>,
Arnd Bergmann <arnd@arndb.de>,
libc-alpha@sourceware.org, David Howells <dhowells@redhat.com>,
Jann Horn <jannh@google.com>, Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
Shuah Khan <shuah@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Michal Hocko <mhocko@suse.com>,
Elena Reshetova <elena.reshetova@intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Roman Gushchin <guro@fb.com>,
Andrea Arcangeli <aarcange@redhat.com>,
Al Viro <viro@zeniv.linux.org.uk>,
Aleksa Sarai <cyphar@cyphar.com>,
"Dmitry V. Levin" <ldv@altlinux.org>,
linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org
Subject: Re: [PATCH v3 1/2] clone3: add CLONE_CLEAR_SIGHAND
Date: Mon, 21 Oct 2019 16:46:33 +0200 [thread overview]
Message-ID: <20191021144633.GA2720@redhat.com> (raw)
In-Reply-To: <20191014104538.3096-1-christian.brauner@ubuntu.com>
On 10/14, Christian Brauner wrote:
>
> The child helper process on Linux posix_spawn must ensure that no signal
> handlers are enabled, so the signal disposition must be either SIG_DFL
> or SIG_IGN. However, it requires a sigprocmask to obtain the current
> signal mask and at least _NSIG sigaction calls to reset the signal
> handlers for each posix_spawn call
Plus the caller has to block/unblock all signals around clone(VM|VFORK).
Can this justify the new CLONE_ flag? Honestly, I have no idea. But the
patch is simple and looks technically correct to me. FWIW,
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
next prev parent reply other threads:[~2019-10-21 14:46 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-14 10:45 [PATCH v3 1/2] clone3: add CLONE_CLEAR_SIGHAND Christian Brauner
2019-10-14 10:45 ` Christian Brauner
2019-10-14 10:45 ` [PATCH v3 2/2] tests: test CLONE_CLEAR_SIGHAND Christian Brauner
2019-10-14 10:45 ` Christian Brauner
2019-10-21 14:46 ` Oleg Nesterov [this message]
2019-10-21 14:46 ` [PATCH v3 1/2] clone3: add CLONE_CLEAR_SIGHAND Oleg Nesterov
2019-10-21 15:12 ` Oleg Nesterov
2019-10-21 15:12 ` Oleg Nesterov
2019-10-21 19:40 ` Christian Brauner
2019-10-21 19:40 ` Christian Brauner
2019-10-21 19:42 ` Christian Brauner
2019-10-21 19:42 ` Christian Brauner
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