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Fri, 15 May 2026 11:49:54 -0400 X-MC-Unique: PVCkdrSANp6znqDPcRhVaA-1 X-Mimecast-MFC-AGG-ID: PVCkdrSANp6znqDPcRhVaA_1778860191 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E4F2D19560A2; Fri, 15 May 2026 15:49:50 +0000 (UTC) Received: from fedora (unknown [10.44.32.66]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id 6A98A1800240; Fri, 15 May 2026 15:49:46 +0000 (UTC) Received: by fedora (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Fri, 15 May 2026 17:49:50 +0200 (CEST) Date: Fri, 15 May 2026 17:49:44 +0200 From: Oleg Nesterov To: Christian Brauner Cc: Minchan Kim , Jann Horn , Linus Torvalds , akpm@linux-foundation.org, hca@linux.ibm.com, linux-s390@vger.kernel.org, david@kernel.org, mhocko@suse.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, surenb@google.com, timmurray@google.com Subject: Re: [PATCH v3] mm: process_mrelease: introduce PROCESS_MRELEASE_REAP_KILL flag Message-ID: References: <20260511214226.937793-1-minchan@kernel.org> <20260515-nachdenken-umbenannt-a90006a46e14@brauner> MIME-Version: 1.0 In-Reply-To: <20260515-nachdenken-umbenannt-a90006a46e14@brauner> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 X-Mimecast-MFC-PROC-ID: 8E1OpzgN48A9LENoGIaAhzfDzRDNgKstQR9WxR0idFA_1778860191 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 9E2FBC0002 X-Stat-Signature: ayt63tbq7uaun1diqx56koho3rqjq763 X-Rspam-User: X-HE-Tag: 1778860201-782370 X-HE-Meta: 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 jrJOMpN2 GnkUXaDIXXmpcBrxWHvheTX77JY8kvtDW8V65kRNE2b8PtfAVy7MreUL380rFz50Ki86oaykVP6/tZFFJ7gslP/BsJufr7xRIFkknSX2zuB9UGw1Py2IpRxMGuFgXSft6W3pQgBPgRt2RAj8xbhnKoplLWKRQ+Ni39RivrFX3uDGwqE4kSkV60J74KJlDuJwutKGMdtwH/OrUneVHJFCDy89kQHLaH3H5kjthwnZhzWC8/a32jWdIsBl5mH3h1uzN42K/s3/LoKl7kuykH16FAK2lMGyhcWobz3mrHAVl+sIHWnqTsYsQe0WPt8GigHP64n2qOvjZeRdlwqRqnyQ6/0dQ1XWMpMpWsvqN89oKvdKAeKlGDRbss988+TiX9bw9QSi/25J0CS2XYTRUlLRkl6ZxUg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 05/15, Christian Brauner wrote: > > Right now we have clear and simple signal sending semantics for pidfds: > > * thread-specific pidfd -> thread-directed signal (unless signal is thread-group scoped by default) > * thread-group pidfd -> thread-group directed signal I don't even understand why this patch uses pidfd to send SIGKILL... > > + reap = reap_kill || task_will_free_mem(p); > > + if (!reap) { > > /* Error only if the work has not been done already */ > > if (!mm_flags_test(MMF_OOM_SKIP, mm)) > > ret = -EINVAL; > > + task_unlock(p); > > + goto put_task; > > } > > + > > + mmgrab(mm); > > task_unlock(p); > > > > - if (!reap) > > - goto drop_mm; > > + if (reap_kill) { > > + ret = kill_all_shared_mm(task, mm); If task_will_free_mem() above succeeded, we do not need to call kill_all_shared_mm() ? Oleg.