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=-7.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 C397FC433DF for ; Tue, 25 Aug 2020 21:32:21 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8410A206EB for ; Tue, 25 Aug 2020 21:32:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="DylhKp38" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8410A206EB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0F3C76B0006; Tue, 25 Aug 2020 17:32:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0A75A6B0007; Tue, 25 Aug 2020 17:32:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EFC6C6B0008; Tue, 25 Aug 2020 17:32:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0033.hostedemail.com [216.40.44.33]) by kanga.kvack.org (Postfix) with ESMTP id DB0646B0006 for ; Tue, 25 Aug 2020 17:32:20 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 5BD0C180AD801 for ; Tue, 25 Aug 2020 21:32:20 +0000 (UTC) X-FDA: 77190389640.27.birth06_5608ca72705f Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin27.hostedemail.com (Postfix) with ESMTP id 302283D663 for ; Tue, 25 Aug 2020 21:32:20 +0000 (UTC) X-HE-Tag: birth06_5608ca72705f X-Filterd-Recvd-Size: 3923 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Tue, 25 Aug 2020 21:32:19 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A45FD206EB; Tue, 25 Aug 2020 21:32:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598391138; bh=Ep3dimXXCaaIGD2nTvOy/HpQVRAxH9on+IsBQT7q0aw=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=DylhKp38oftKSzESaH0wfO3FZOtfHqiZuQNZBvxuUOKr0YRwxDpYgzjudgLjH352k fxtXUYczJe/GLimohJhl6F8GNVlfQ+vR9e7VxpPPhxYgIVa0G0AoSQcFb74e3MKfbp SVcgQDghBHBjuHlfMBqrnO0Gb2X4CGqWISqgomTQ= Date: Tue, 25 Aug 2020 14:32:18 -0700 From: Andrew Morton To: kernel test robot Cc: Linux Memory Management List , Joao Martins , Vishal L Verma , Dan Williams Subject: Re: [linux-next:master] BUILD REGRESSION 3a00d3dfd4b68b208ecd5405e676d06c8ad6bb63 Message-Id: <20200825143218.7fc406bf642ad7f0cc9cfb26@linux-foundation.org> In-Reply-To: <5f457d73.gsRq3vmXOfOBWd0d%lkp@intel.com> References: <5f457d73.gsRq3vmXOfOBWd0d%lkp@intel.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 302283D663 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 26 Aug 2020 05:06:59 +0800 kernel test robot wrote: > drivers/dax/bus.c:626 alloc_dev_dax_range() error: potential null dereference 'alloc'. (__request_region returns null) > drivers/dax/bus.c:626 alloc_dev_dax_range() error: we previously assumed 'alloc' could be null (see line 610) yes, looks fishy: alloc = __request_region(res, start, size, dev_name(dev), 0); if (!alloc && !dev_dax->nr_range) { /* * If we adjusted an existing @ranges leave it alone, * but if this was an empty set of ranges nothing else * will release @ranges, so do it now. */ kfree(ranges); return -ENOMEM; } ... .start = alloc->start, Added by "[PATCH v4 18/23] device-dax: Add dis-contiguous resource support", https://lkml.kernel.org/r/159643104304.4062302.16561669534797528660.stgit@dwillia2-desk3.amr.corp.intel.com > drivers/dax/device.c:111:21: warning: variable 'dax_region' set but not used [-Wunused-but-set-variable] yup, "device-dax: make align a per-device property" needs --- a/drivers/dax/device.c~device-dax-make-align-a-per-device-property-fix +++ a/drivers/dax/device.c @@ -108,7 +108,6 @@ static vm_fault_t __dev_dax_pmd_fault(st { unsigned long pmd_addr = vmf->address & PMD_MASK; struct device *dev = &dev_dax->dev; - struct dax_region *dax_region; phys_addr_t phys; pgoff_t pgoff; unsigned int fault_size = PMD_SIZE; @@ -116,7 +115,6 @@ static vm_fault_t __dev_dax_pmd_fault(st if (check_vma(dev_dax, vmf->vma, __func__)) return VM_FAULT_SIGBUS; - dax_region = dev_dax->region; if (dev_dax->align > PMD_SIZE) { dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n", dev_dax->align, fault_size); @@ -151,7 +149,6 @@ static vm_fault_t __dev_dax_pud_fault(st { unsigned long pud_addr = vmf->address & PUD_MASK; struct device *dev = &dev_dax->dev; - struct dax_region *dax_region; phys_addr_t phys; pgoff_t pgoff; unsigned int fault_size = PUD_SIZE; @@ -160,7 +157,6 @@ static vm_fault_t __dev_dax_pud_fault(st if (check_vma(dev_dax, vmf->vma, __func__)) return VM_FAULT_SIGBUS; - dax_region = dev_dax->region; if (dev_dax->align > PUD_SIZE) { dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n", dev_dax->align, fault_size); _