Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18;
MIME-Version: 1.0
References: <878rrrh32q.fsf_-_@email.froward.int.ebiederm.org> <20220426225211.308418-4-ebiederm@xmission.com>
In-Reply-To: <20220426225211.308418-4-ebiederm@xmission.com>
From:   Max Filippov <jcmvbkbc@gmail.com>
Date:   Tue, 26 Apr 2022 16:33:24 -0700
Message-ID: <CAMo8BfJdDJ2tWPp0vNZ0SF2HkRGsytoVhnsnRMDcbSmGByH8zA@mail.gmail.com>
Subject: Re: [PATCH 4/9] ptrace/xtensa: Replace PT_SINGLESTEP with TIF_SINGLESTEP
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, rjw@rjwysocki.net,
        Oleg Nesterov <oleg@redhat.com>,
        Ingo Molnar <mingo@kernel.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        dietmar.eggemann@arm.com, Steven Rostedt <rostedt@goodmis.org>,
        mgorman@suse.de, Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Will Deacon <will@kernel.org>, Tejun Heo <tj@kernel.org>,
        linux-pm@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>,
        Richard Weinberger <richard@nod.at>,
        Anton Ivanov <anton.ivanov@cambridgegreys.com>,
        Johannes Berg <johannes@sipsolutions.net>,
        linux-um@lists.infradead.org, Chris Zankel <chris@zankel.net>,
        inux-xtensa@linux-xtensa.org, Kees Cook <keescook@chromium.org>,
        Jann Horn <jannh@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue, Apr 26, 2022 at 3:52 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
>
> xtensa is the last user of the PT_SINGLESTEP flag.  Changing tsk->ptrace in
> user_enable_single_step and user_disable_single_step without locking could
> potentiallly cause problems.
>
> So use a thread info flag instead of a flag in tsk->ptrace.  Use TIF_SINGLESTEP
> that xtensa already had defined but unused.
>
> Remove the definitions of PT_SINGLESTEP and PT_BLOCKSTEP as they have no more users.
>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
> ---
>  arch/xtensa/kernel/ptrace.c | 4 ++--
>  arch/xtensa/kernel/signal.c | 4 ++--
>  include/linux/ptrace.h      | 6 ------
>  3 files changed, 4 insertions(+), 10 deletions(-)

Acked-by: Max Filippov <jcmvbkbc@gmail.com>

-- 
Thanks.
-- Max