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Mon, 03 Feb 2025 13:49:40 -0500 X-MC-Unique: a840UdVKOzupfVM_af1Y2A-1 X-Mimecast-MFC-AGG-ID: a840UdVKOzupfVM_af1Y2A Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 96B9519560AA; Mon, 3 Feb 2025 18:49:38 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.224.72]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id E26B519560A3; Mon, 3 Feb 2025 18:49:35 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Mon, 3 Feb 2025 19:49:12 +0100 (CET) Date: Mon, 3 Feb 2025 19:49:08 +0100 From: Oleg Nesterov To: Mateusz Guzik Cc: ebiederm@xmission.com, brauner@kernel.org, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 5/6] pid: perform free_pid() calls outside of tasklist_lock Message-ID: <20250203184908.GD1003@redhat.com> References: <20250201163106.28912-1-mjguzik@gmail.com> <20250201163106.28912-6-mjguzik@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250201163106.28912-6-mjguzik@gmail.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: A18F1140019 X-Stat-Signature: ftj83rrjhhj9im8um3wy8k45kyd7z859 X-Rspam-User: X-HE-Tag: 1738608586-478709 X-HE-Meta: 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 XZf1uaK1 jSnV3QNfgKGvPTZlgQXMbFMvx4RtxGor1zyTzD48pCfT3bUFvTFGVzDNYKo/EmOkgcf6vS8BAdYtPIrZoogVdlTLBpYX5h903hRyQ1fUjisFzka4e/kUhQKcSkMZpZqF/K8q2A7fvF0zsSiIepnPrpQeO8JEv88SWGfqDLK7OnqQWbR0ibI7t2HkUPe9efRQKaGgiMP0BTvSQOuNJgcXPZiuLbwYrHHJYiqbhQurqN6wbXXgGAKcY/SSMoVN3xOHgS3rDF3n1Qs1Z7JXPlGswv62f4ApfbUJBN37WJCI8sHBvauYThXj455VvmBGMuE5UeLsdJ23SjZXW63AMcx0aCoYXZjr598KaCL75ii2tc5vi5aAYm7cQxH82kUXGttlld832 X-Bogosity: Ham, tests=bogofilter, spamicity=0.002635, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: To avoid the confusion, my question and a note are absolutely offtopic. On 02/01, Mateusz Guzik wrote: > > @@ -1085,6 +1085,7 @@ SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) > { > struct task_struct *p; > struct task_struct *group_leader = current->group_leader; > + struct pid *pids[PIDTYPE_MAX] = { 0 }; Could you remind me why struct pid *pids[PIDTYPE_MAX] = {}; is not right? I seem to knew it some time before, but can't recall... And just for the record, a note for myself. I need to recheck, but it seems that the comment above flush_sigqueue(&tsk->pending) in __exit_signal() is obsolete, so with some minimal changes we can move more work outside of tasklist. Oleg.