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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 5BA42C73C53 for ; Tue, 9 Jul 2019 22:36:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2298420665 for ; Tue, 9 Jul 2019 22:36:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="THZRHUUf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726996AbfGIWgL (ORCPT ); Tue, 9 Jul 2019 18:36:11 -0400 Received: from hqemgate16.nvidia.com ([216.228.121.65]:1978 "EHLO hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726133AbfGIWgK (ORCPT ); Tue, 9 Jul 2019 18:36:10 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Tue, 09 Jul 2019 15:36:08 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Tue, 09 Jul 2019 15:36:09 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Tue, 09 Jul 2019 15:36:09 -0700 Received: from HQMAIL102.nvidia.com (172.18.146.10) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Tue, 9 Jul 2019 22:36:09 +0000 Received: from HQMAIL101.nvidia.com (172.20.187.10) by HQMAIL102.nvidia.com (172.18.146.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Tue, 9 Jul 2019 22:36:09 +0000 Received: from hqnvemgw01.nvidia.com (172.20.150.20) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Tue, 9 Jul 2019 22:36:09 +0000 Received: from rcampbell-dev.nvidia.com (Not Verified[10.110.48.66]) by hqnvemgw01.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Tue, 09 Jul 2019 15:36:09 -0700 From: Ralph Campbell To: CC: , Ralph Campbell , Andrew Morton , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , "Kirill A. Shutemov" , Mike Kravetz Subject: [PATCH] mm/hmm: Fix bad subpage pointer in try_to_unmap_one Date: Tue, 9 Jul 2019 15:35:56 -0700 Message-ID: <20190709223556.28908-1-rcampbell@nvidia.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-NVConfidentiality: public Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1562711768; bh=WmDfProy1Dp6O/d7UXR/pCuB4a9yi2oJwRAiLHXR8FI=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: MIME-Version:X-NVConfidentiality:Content-Type: Content-Transfer-Encoding; b=THZRHUUfPOzbOu0G+mUFBwdXTkVaIRyYUhTmyBN+kxFrZrkuCZMB0QIbsgRmMgdxv fhWfhYtObglVZpAYUg9wae+eqbuKmR0WpWK1LgzKnYNDm90H4nC5PYbjMibG+FexFY ws73FQ7OyJbc5tGO4q0fM3859mCHmEWKlrqf/SNrUFffaP+vIxlTvmLpXnU87yW+LE GDaFsFG9TOopI7e6oMVFJP+A2eSqnP7NlydABKF5OpHYbq6I2XMDctzEZpY/8Ocvbt 3kYpx8pU7JykioEa0fCpomdY+HONkVJg0Q0yDCVmmeO9IL42bJ2OA6u2X+0WLdnjKn Ki52Yfw+aFsCQ== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When migrating a ZONE device private page from device memory to system memory, the subpage pointer is initialized from a swap pte which computes an invalid page pointer. A kernel panic results such as: BUG: unable to handle page fault for address: ffffea1fffffffc8 Initialize subpage correctly before calling page_remove_rmap(). Signed-off-by: Ralph Campbell Cc: Andrew Morton Cc: "J=C3=A9r=C3=B4me Glisse" Cc: "Kirill A. Shutemov" Cc: Mike Kravetz --- mm/rmap.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/rmap.c b/mm/rmap.c index e5dfe2ae6b0d..ec1af8b60423 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1476,6 +1476,7 @@ static bool try_to_unmap_one(struct page *page, struc= t vm_area_struct *vma, * No need to invalidate here it will synchronize on * against the special swap migration pte. */ + subpage =3D page; goto discard; } =20 --=20 2.20.1