Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755259AbbFMGvm (ORCPT ); Sat, 13 Jun 2015 02:51:42 -0400 Received: from mail-wi0-f174.google.com ([209.85.212.174]:36396 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753466AbbFMGtg (ORCPT ); Sat, 13 Jun 2015 02:49:36 -0400 Date: Sat, 13 Jun 2015 08:49:31 +0200 From: Ingo Molnar To: Oleg Nesterov Cc: linux-kernel@vger.kernel.org, linux-mml@vger.kernel.org, Andy Lutomirski , Andrew Morton , Denys Vlasenko , Brian Gerst , Peter Zijlstra , Borislav Petkov , "H. Peter Anvin" , Linus Torvalds , Thomas Gleixner , Waiman Long Subject: Re: [PATCH 06/12] x86/mm: Enable and use the arch_pgd_init_late() method Message-ID: <20150613064930.GB13835@gmail.com> References: <1434031637-9091-1-git-send-email-mingo@kernel.org> <1434031637-9091-7-git-send-email-mingo@kernel.org> <20150612225000.GA24699@redhat.com> <20150612225711.GB24699@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150612225711.GB24699@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 651 Lines: 25 * Oleg Nesterov wrote: > On 06/13, Oleg Nesterov wrote: > > > > Afaics, we need to ensure that: > > > > > + if (pgd_val(*pgd_src)) > > > + WRITE_ONCE(*pgd_dst, *pgd_src); > > > > either we notice the recent update of this PGD, or (say) the subsequent > > sync_global_pgds() can miss the child. > > and perhaps !pgd_none(pgd_src) will look better. Indeed - fixed. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/