From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6D6C6C3A59B for ; Sat, 17 Aug 2019 08:13:06 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E830A2077C for ; Sat, 17 Aug 2019 08:13:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E830A2077C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=bugzilla.kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 469XxW5BGyzDqw8 for ; Sat, 17 Aug 2019 18:13:03 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=bugzilla.kernel.org (client-ip=198.145.29.98; helo=mail.wl.linuxfoundation.org; envelope-from=bugzilla-daemon@bugzilla.kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=bugzilla.kernel.org Received: from mail.wl.linuxfoundation.org (mail.wl.linuxfoundation.org [198.145.29.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 469Xsy0P35zDrhR for ; Sat, 17 Aug 2019 18:09:56 +1000 (AEST) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C551D28A80 for ; Sat, 17 Aug 2019 08:09:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B9B5128AA1; Sat, 17 Aug 2019 08:09:52 +0000 (UTC) From: bugzilla-daemon@bugzilla.kernel.org To: linuxppc-dev@lists.ozlabs.org Subject: [Bug 204371] BUG kmalloc-4k (Tainted: G W ): Object padding overwritten Date: Sat, 17 Aug 2019 08:09:51 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Memory Management X-Bugzilla-Component: Slab Allocator X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: christophe.leroy@c-s.fr X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: akpm@linux-foundation.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-Virus-Scanned: ClamAV using ClamSMTP X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" https://bugzilla.kernel.org/show_bug.cgi?id=3D204371 --- Comment #38 from Christophe Leroy (christophe.leroy@c-s.fr) --- Le 30/07/2019 =C3=A0 20:52, bugzilla-daemon@bugzilla.kernel.org a =C3=A9cri= t=C2=A0: > https://bugzilla.kernel.org/show_bug.cgi?id=3D204371 >=20 > --- Comment #2 from Andrew Morton (akpm@linux-foundation.org) --- > (switched to email. Please respond via emailed reply-to-all, not via the > bugzilla web interface). Reply all replies to bugzilla-daemon@bugzilla.kernel.org only. [...] >=20 > cc'ing various people here. Hum ... only got that email through the bugzilla interface, and CC'ed=20 people don't show up. >=20 > I suspect proc_cgroup_show() is innocent and that perhaps > bpf_prepare_filter() had a memory scribble. iirc there has been at > least one recent pretty serious bpf fix applied recently. Can others > please take a look? >=20 > (Seriously - please don't modify this report via the bugzilla web interfa= ce!) >=20 Haven't got the original CC'ed list, so please reply with missing Cc's=20 if any. We have well progressed on this case. Erhard made a relation being this "Object padding overwritten" issue=20 arising on any driver, and the presence of the BTRFS driver. Then he was able to bisect the issue to: commit 69d2480456d1baf027a86e530989d7bedd698d5f Author: David Sterba Date: Fri Jun 29 10:56:44 2018 +0200 btrfs: use copy_page for copying pages instead of memcpy Use the helper that's possibly optimized for full page copies. Signed-off-by: David Sterba After looking in the code, it has appeared that some of the said "pages"=20 were allocated with "kzalloc()". Using the patch https://patchwork.ozlabs.org/patch/1148033/ Erhard=20 confirmed that some btrfs functions were calling copy_page() with=20 misaligned destinations. copy_page(), at least on powerpc, expects cache aligned destination. The patch https://patchwork.ozlabs.org/patch/1148606/ fixes the issue. Christophe --- L'absence de virus dans ce courrier =C3=A9lectronique a =C3=A9t=C3=A9 v=C3= =A9rifi=C3=A9e par le logiciel antivirus Avast. https://www.avast.com/antivirus --=20 You are receiving this mail because: You are on the CC list for the bug.=