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Sun, 8 Nov 2026 18:59:29 +0000 (UTC) Received: from onestero-thinkpadp1gen7.tpbc.csb (headnet04.pony-001.prod.iad2.dc.redhat.com [10.2.32.116]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id D7BB31956041; Sun, 8 Nov 2026 18:59:26 +0000 (UTC) Received: by onestero-thinkpadp1gen7.tpbc.csb (nbSMTP-1.00) for uid 13628 oleg@redhat.com; Sun, 8 Nov 2026 19:59:29 +0100 (CET) Date: Sun, 8 Nov 2026 19:59:25 +0100 From: Oleg Nesterov To: Zhao Gongyi Cc: catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, ruanjinjie@huawei.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] arm64: ptrace: don't warn on missing siginfo in a group-stop Message-ID: References: <20261105113051.97810-1-zhaogongyi@bytedance.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261105113051.97810-1-zhaogongyi@bytedance.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 On 11/05, Zhao Gongyi wrote: > > --- a/arch/arm64/kernel/ptrace.c > +++ b/arch/arm64/kernel/ptrace.c > @@ -573,8 +573,8 @@ static void update_syscall_orig_x0_after_ptrace(struct task_struct *target) > if (regs->syscallno == NO_SYSCALL) > return; > > - /* We should only be called when target is in a ptrace stop */ > - if (WARN_ON_ONCE(!info)) > + /* Non-seized group-stops do not provide siginfo (see do_jobctl_trap()). */ > + if (!info) > return; First of all, FWIW Acked-by: Oleg Nesterov This change is "obviously good" and doesn't change the current behaviour. ---------------------------------------------------------------------------- But can't resist... The old comment was obviously wrong, the new one doesn't look clear to me. It correctly explains why info can be NULL, but not why we should not update orig_x0 in this case. May be it should just say that exit-stop always comes with info != NULL? Nevermind, I leave this to you, Catalin, and Will. And I see another email from Will, I'll try to reply tomorrow. In any case, let me repeat, the patch looks fine to me. Oleg.