From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oleg Nesterov Date: Thu, 05 May 2022 17:27:45 +0000 Subject: Re: [PATCH v3 08/11] ptrace: Admit ptrace_stop can generate spuriuos SIGTRAPs Message-Id: <20220505172744.GA13664@redhat.com> List-Id: References: <87k0b0apne.fsf_-_@email.froward.int.ebiederm.org> <20220504224058.476193-8-ebiederm@xmission.com> <20220505150158.GB13929@redhat.com> <87a6bv7v49.fsf@email.froward.int.ebiederm.org> In-Reply-To: <87a6bv7v49.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, mingo@kernel.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de, bigeasy@linutronix.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, Kees Cook , Jann Horn , linux-ia64@vger.kernel.org On 05/05, Eric W. Biederman wrote: > > And yes that WARN_ON_ONCE can trigger on PREEMPT_RT but that is just > because PREMPT_RT is currently broken with respect to ptrace. Which > makes a WARN_ON_ONCE appropriate. Yes agreed. In this case WARN_ON_ONCE() can help a user to understand that a failure was caused by the kernel problem which we need to fix anyway. Oleg.