Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965425AbaGQQXx (ORCPT ); Thu, 17 Jul 2014 12:23:53 -0400 Received: from smtp4-g21.free.fr ([212.27.42.4]:5688 "EHLO smtp4-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757600AbaGQQXt (ORCPT ); Thu, 17 Jul 2014 12:23:49 -0400 Date: Thu, 17 Jul 2014 18:23:45 +0200 From: Guillaume Morin To: Naoya Horiguchi , Hugh Dickins Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [BUG] new copy_hugetlb_page_range() causing crashes Message-ID: <20140717162345.GA8550@bender.morinfr.org> Mail-Followup-To: Naoya Horiguchi , Hugh Dickins , linux-kernel@vger.kernel.org, stable@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline 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 Naoya, Hugh, I am seeing lots of crashes with the new copy_hugetlb_page_range() code added by 4a705fef986231a3e7a6b1a6d3c37025f021f49f for some set of programs. Specifically, I am running some test programs which use huge pages for malloc (through libhugetlbfs with HUGETLB_MORECORE=yes and HUGETLB_NO_PREFAULT= set) that also do fork() a lot. The crashes are very diverse: assertion failures in malloc() or the python GC code, some SIGSEGV as well. I started observing these crashes with 3.4.98 and 3.14.12 which just got a backport of the patch above (as 2bcdd4933ff4dc46445dcae93cb37c648283b782 in the stable branch). The 3.4 and 3.14 patches are identical to the upstream commit so that's not a patch backport issue. If I revert only 2bcdd4933ff4dc46445dcae93cb37c648283b782 in my 3.4 tree, the crashes disappear right away and everything is stable. -- Guillaume Morin -- 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/