From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753078AbeBLRDa (ORCPT ); Mon, 12 Feb 2018 12:03:30 -0500 Received: from mail-qt0-f182.google.com ([209.85.216.182]:41628 "EHLO mail-qt0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752745AbeBLRD2 (ORCPT ); Mon, 12 Feb 2018 12:03:28 -0500 X-Google-Smtp-Source: AH8x224enHG1Js2g63B6y0/L6hW/eusKhkKp29IDIUlJYCMqGnR69IXfUGTo0vqlPA86VHOxoYYU7w== Date: Mon, 12 Feb 2018 09:03:25 -0800 From: Tejun Heo To: Daniel Borkmann Cc: dennisszhou@gmail.com, Dmitry Vyukov , syzbot , Alexei Starovoitov , netdev , LKML , syzkaller-bugs@googlegroups.com Subject: Re: lost connection to test machine (4) Message-ID: <20180212170325.GW695913@devbig577.frc2.facebook.com> References: <001a113f8734783e94056505f8fd@google.com> <00c45ca8-305d-1818-e974-a9903c8494b8@iogearbox.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <00c45ca8-305d-1818-e974-a9903c8494b8@iogearbox.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Daniel. On Mon, Feb 12, 2018 at 06:00:13PM +0100, Daniel Borkmann wrote: > [ +Dennis, +Tejun ] > > Looks like we're stuck in percpu allocator with key/value size of 4 bytes > each and large number of entries (max_entries) in the reproducer in above > link. > > Could we have some __GFP_NORETRY semantics and let allocations fail instead > of triggering OOM killer? For some part, maybe, but not generally. The virt area allocation goes down to page table allocation which is hard coded to use GFP_KERNEL in arch mm code. Thanks. -- tejun