From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Andrzej Siewior Date: Fri, 20 May 2022 09:19:02 +0000 Subject: Re: [PATCH 00/16] ptrace: cleanups and calling do_cldstop with only siglock Message-Id: List-Id: References: <20220421150248.667412396@infradead.org> <20220421150654.817117821@infradead.org> <87czhap9dy.fsf@email.froward.int.ebiederm.org> <878rrrh32q.fsf_-_@email.froward.int.ebiederm.org> <87k0b7v9yk.fsf_-_@email.froward.int.ebiederm.org> <87k0b0apne.fsf_-_@email.froward.int.ebiederm.org> <87a6bv6dl6.fsf_-_@email.froward.int.ebiederm.org> <871qwq5ucx.fsf_-_@email.froward.int.ebiederm.org> In-Reply-To: <871qwq5ucx.fsf_-_@email.froward.int.ebiederm.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Eric W. Biederman" Cc: linux-kernel@vger.kernel.org, rjw@rjwysocki.net, oleg@redhat.com, mingo@kernel.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de, Will Deacon , tj@kernel.org, linux-pm@vger.kernel.org, Peter Zijlstra , Richard Weinberger , Anton Ivanov , Johannes Berg , linux-um@lists.infradead.org, Chris Zankel , Max Filippov , linux-xtensa@linux-xtensa.org, Jann Horn , Kees Cook , linux-ia64@vger.kernel.org, Robert O'Callahan , Kyle Huey , Richard Henderson , Ivan Kokshaysky , Matt Turner , Jason Wessel , Daniel Thompson , Douglas Anderson , Douglas Miller , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras On 2022-05-18 17:49:50 [-0500], Eric W. Biederman wrote: > After this set of changes only cgroup_enter_frozen should remain a > stumbling block for PREEMPT_RT in the ptrace_stop path. Yes, I can confirm that. I have no systemd-less system at hand which means I can't boot a kernel without CGROUP support. But after removing cgroup_{enter|leave}_frozen() in ptrace_stop() I don't see the problems I saw earlier. Sebastian