From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751962AbeFANl7 (ORCPT ); Fri, 1 Jun 2018 09:41:59 -0400 Received: from mx2.suse.de ([195.135.220.15]:55427 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751852AbeFANl4 (ORCPT ); Fri, 1 Jun 2018 09:41:56 -0400 Date: Fri, 1 Jun 2018 15:41:54 +0200 From: Michal Hocko To: Alex Richman Cc: linux-man@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: mlock() confusing 1 half of system RAM limit Message-ID: <20180601134154.GD15278@dhcp22.suse.cz> References: <20180601114425.GA15686@dhcp22.suse.cz> <3e33edd7-89dd-1c09-77df-a2ae23c208f1@gblabs.co.uk> <20180601130524.GB15278@dhcp22.suse.cz> <1ae5c450-1ffe-cf15-e878-b40f30c0acc3@gblabs.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1ae5c450-1ffe-cf15-e878-b40f30c0acc3@gblabs.co.uk> User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 01-06-18 14:24:23, Alex Richman wrote: > Ah, that's it.  Increased the limit on the mount and it works fine now. Well, it is hidden very well. It is not until the page fault time (or get_user_pages aka __mm_populate) when the operation fails and remasks ENOSPC -> VM_FAULT_SIGBUS -> EFAULT -> ENOMEM on the way. -- Michal Hocko SUSE Labs