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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 22215C0650F for ; Thu, 8 Aug 2019 09:37:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E809C20880 for ; Thu, 8 Aug 2019 09:37:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732419AbfHHJhE (ORCPT ); Thu, 8 Aug 2019 05:37:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37894 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731122AbfHHJhD (ORCPT ); Thu, 8 Aug 2019 05:37:03 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A7A6530BD1CD; Thu, 8 Aug 2019 09:37:03 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-116-144.ams2.redhat.com [10.36.116.144]) by smtp.corp.redhat.com (Postfix) with ESMTP id 640165EE1D; Thu, 8 Aug 2019 09:37:03 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id 949A917444; Thu, 8 Aug 2019 11:37:02 +0200 (CEST) From: Gerd Hoffmann To: dri-devel@lists.freedesktop.org Cc: tzimmermann@suse.de, Christoph Hellwig , "Martin K . Petersen" , "James E.J. Bottomley" , linux-scsi@vger.kernel.org (open list:SCSI SUBSYSTEM), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v3 1/8] scsi: core: fix the dma_max_mapping_size call Date: Thu, 8 Aug 2019 11:36:55 +0200 Message-Id: <20190808093702.29512-2-kraxel@redhat.com> In-Reply-To: <20190808093702.29512-1-kraxel@redhat.com> References: <20190808093702.29512-1-kraxel@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Thu, 08 Aug 2019 09:37:03 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christoph Hellwig We should only call dma_max_mapping_size for devices that have a DMA mask set, otherwise we can run into a NULL pointer dereference that will crash the system. Also we need to do right shift to get the sectors from the size in bytes, not a left shift. Fixes: bdd17bdef7d8 ("scsi: core: take the DMA max mapping size into account") Reported-by: Bart Van Assche Reported-by: Ming Lei Tested-by: Guilherme G. Piccoli Signed-off-by: Christoph Hellwig Signed-off-by: Martin K. Petersen (cherry picked from commit 1b5d9a6e98350e0713b4faa1b04e8f239f63b581) --- drivers/scsi/scsi_lib.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 9381171c2fc0..11e64b50497f 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1784,8 +1784,10 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize); } - shost->max_sectors = min_t(unsigned int, shost->max_sectors, - dma_max_mapping_size(dev) << SECTOR_SHIFT); + if (dev->dma_mask) { + shost->max_sectors = min_t(unsigned int, shost->max_sectors, + dma_max_mapping_size(dev) >> SECTOR_SHIFT); + } blk_queue_max_hw_sectors(q, shost->max_sectors); if (shost->unchecked_isa_dma) blk_queue_bounce_limit(q, BLK_BOUNCE_ISA); -- 2.18.1