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[209.132.183.28]) by mx.google.com with ESMTPS id y12si2904848qty.70.2019.04.29.14.31.58 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 29 Apr 2019 14:31:58 -0700 (PDT) Received-SPF: pass (google.com: domain of aarcange@redhat.com designates 209.132.183.28 as permitted sender) client-ip=209.132.183.28; Authentication-Results: mx.google.com; spf=pass (google.com: domain of aarcange@redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=aarcange@redhat.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id EEDB9309D28F; Mon, 29 Apr 2019 21:31:57 +0000 (UTC) Received: from ultra.random (ovpn-123-98.rdu2.redhat.com [10.10.123.98]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 242D45EE06; Mon, 29 Apr 2019 21:31:55 +0000 (UTC) Date: Mon, 29 Apr 2019 10:37:11 -0400 From: Andrea Arcangeli To: zhong jiang Cc: Andrew Morton , Michal Hocko , linux-mm@kvack.org, syzkaller-bugs@googlegroups.com, syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com, Mike Rapoport , Mike Kravetz , Peter Xu , Dmitry Vyukov Subject: Re: [PATCH 1/1 v2] userfaultfd: use RCU to free the task struct when fork fails Message-ID: <20190429143711.GA11265@redhat.com> References: <20190327084912.GC11927@dhcp22.suse.cz> <20190429035752.4508-1-aarcange@redhat.com> <5CC69B6C.9090608@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5CC69B6C.9090608@huawei.com> User-Agent: Mutt/1.11.4 (2019-03-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Mon, 29 Apr 2019 21:31:58 +0000 (UTC) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hello, On Mon, Apr 29, 2019 at 02:36:28PM +0800, zhong jiang wrote: > if we disable the CONFIG_MEMCG, __delay_free_task will not to be used. Yes, the compiler optimizes that away at build time. Thanks, Andrea