From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f70.google.com (mail-wm0-f70.google.com [74.125.82.70]) by kanga.kvack.org (Postfix) with ESMTP id A2FFA6B0289 for ; Wed, 26 Oct 2016 05:15:45 -0400 (EDT) Received: by mail-wm0-f70.google.com with SMTP id i128so12230271wme.11 for ; Wed, 26 Oct 2016 02:15:45 -0700 (PDT) Received: from mail-wm0-f41.google.com (mail-wm0-f41.google.com. [74.125.82.41]) by mx.google.com with ESMTPS id x14si2040247wmf.65.2016.10.26.02.15.44 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 26 Oct 2016 02:15:44 -0700 (PDT) Received: by mail-wm0-f41.google.com with SMTP id e69so13857239wmg.0 for ; Wed, 26 Oct 2016 02:15:44 -0700 (PDT) Date: Wed, 26 Oct 2016 11:15:43 +0200 From: Michal Hocko Subject: Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls Message-ID: <20161026091542.GD18382@dhcp22.suse.cz> References: <20161025233609.5601-1-lstoakes@gmail.com> <20161025234631.GA5946@lucifer> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161025234631.GA5946@lucifer> Sender: owner-linux-mm@kvack.org List-ID: To: Lorenzo Stoakes Cc: linux-mm@kvack.org, Linus Torvalds , Jan Kara , Hugh Dickins , Dave Hansen , Rik van Riel , Mel Gorman , Andrew Morton , Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , kvm@vger.kernel.org, linux-kernel@vger.kernel.org On Wed 26-10-16 00:46:31, Lorenzo Stoakes wrote: > The holdout for unexporting __get_user_pages_unlocked() is its invocation in > mm/process_vm_access.c: process_vm_rw_single_vec(), as this definitely _does_ > seem to invoke VM_FAULT_RETRY behaviour which get_user_pages_remote() will not > trigger if we were to replace it with the latter. I am not sure I understand. Prior to 1e9877902dc7e this used get_user_pages_unlocked. What prevents us from reintroducing it with FOLL_REMOVE which was meant to be added by the above commit? Or am I missing your point? -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org