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=-5.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 3C9ABC4360F for ; Wed, 3 Apr 2019 08:14:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F2B1821473 for ; Wed, 3 Apr 2019 08:14:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554279279; bh=NjzXhV8B4d4khp9HSWu9AlaIUG8DfMNk7Jn/ox0oZ5M=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=V6lZsjWikzujXBOBZBdfhIStsCHuYZQ6BfQaVSgHJHO4HrqWAkFcl7yIlp9QykcEO btZ2Pc+fo0Pm1P9To0CeANE6TeWHKHYqqvtBdYvxxG8EelHHNEE1RnQLhl+NShFoqJ ch6mwYaCihQlEElED9CvhcBvuhB02qsLz/pyQOus= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728774AbfDCIOh (ORCPT ); Wed, 3 Apr 2019 04:14:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:57988 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726004AbfDCIOh (ORCPT ); Wed, 3 Apr 2019 04:14:37 -0400 Received: from localhost (unknown [195.134.171.12]) (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 E42EB2084C; Wed, 3 Apr 2019 08:14:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554279276; bh=NjzXhV8B4d4khp9HSWu9AlaIUG8DfMNk7Jn/ox0oZ5M=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=J8lhENZXa8FnQcUv1zJJIPVdpivTGh6g4OgCO/Y4nKrpng9NTWkBX8XCuq08tCOfN cGxThNXMQL7mpb++ovBxMgUG2jdr1/j8d0F6yVh01M0gxDR9sM62mdZwT2mWfzSDTR BkstukOHVlOCuY/fhdQA7WAJoN+KmkEBJbeXyfgQ= Date: Wed, 3 Apr 2019 10:14:33 +0200 From: Greg KH To: John Garry Cc: rafael@kernel.org, linuxarm@huawei.com, chenxiang66@hisilicon.com, robin.murphy@arm.com, geert@linux-m68k.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, robh@kernel.org, hch@lst.de Subject: Re: [PATCH] driver core: Postpone DMA tear-down until after devres release for probe failure Message-ID: <20190403081433.GA13222@kroah.com> References: <1553767685-27077-1-git-send-email-john.garry@huawei.com> <703aca1f-9475-b50d-624a-5f1ceea2c3b2@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <703aca1f-9475-b50d-624a-5f1ceea2c3b2@huawei.com> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 03, 2019 at 09:02:36AM +0100, John Garry wrote: > On 28/03/2019 10:08, John Garry wrote: > > In commit 376991db4b64 ("driver core: Postpone DMA tear-down until after > > devres release"), we changed the ordering of tearing down the device DMA > > ops and releasing all the device's resources; this was because the DMA ops > > should be maintained until we release the device's managed DMA memories. > > > > Hi all, > > A friendly reminder on this patch... I didn't see any update. > > I thought that it had some importance. > > Thanks, > John > > > However, we have seen another crash on an arm64 system when a > > device driver probe fails: > > > > hisi_sas_v3_hw 0000:74:02.0: Adding to iommu group 2 > > scsi host1: hisi_sas_v3_hw > > BUG: Bad page state in process swapper/0 pfn:313f5 > > page:ffff7e0000c4fd40 count:1 mapcount:0 > > mapping:0000000000000000 index:0x0 > > flags: 0xfffe00000001000(reserved) > > raw: 0fffe00000001000 ffff7e0000c4fd48 ffff7e0000c4fd48 > > 0000000000000000 > > raw: 0000000000000000 0000000000000000 00000001ffffffff > > 0000000000000000 > > page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set > > bad because of flags: 0x1000(reserved) > > Modules linked in: > > CPU: 49 PID: 1 Comm: swapper/0 Not tainted > > 5.1.0-rc1-43081-g22d97fd-dirty #1433 > > Hardware name: Huawei D06/D06, BIOS Hisilicon D06 UEFI > > RC0 - V1.12.01 01/29/2019 > > Call trace: > > dump_backtrace+0x0/0x118 > > show_stack+0x14/0x1c > > dump_stack+0xa4/0xc8 > > bad_page+0xe4/0x13c > > free_pages_check_bad+0x4c/0xc0 > > __free_pages_ok+0x30c/0x340 > > __free_pages+0x30/0x44 > > __dma_direct_free_pages+0x30/0x38 > > dma_direct_free+0x24/0x38 > > dma_free_attrs+0x9c/0xd8 > > dmam_release+0x20/0x28 > > release_nodes+0x17c/0x220 > > devres_release_all+0x34/0x54 > > really_probe+0xc4/0x2c8 > > driver_probe_device+0x58/0xfc > > device_driver_attach+0x68/0x70 > > __driver_attach+0x94/0xdc > > bus_for_each_dev+0x5c/0xb4 > > driver_attach+0x20/0x28 > > bus_add_driver+0x14c/0x200 > > driver_register+0x6c/0x124 > > __pci_register_driver+0x48/0x50 > > sas_v3_pci_driver_init+0x20/0x28 > > do_one_initcall+0x40/0x25c > > kernel_init_freeable+0x2b8/0x3c0 > > kernel_init+0x10/0x100 > > ret_from_fork+0x10/0x18 > > Disabling lock debugging due to kernel taint > > BUG: Bad page state in process swapper/0 pfn:313f6 > > page:ffff7e0000c4fd80 count:1 mapcount:0 > > mapping:0000000000000000 index:0x0 > > [ 89.322983] flags: 0xfffe00000001000(reserved) > > raw: 0fffe00000001000 ffff7e0000c4fd88 ffff7e0000c4fd88 > > 0000000000000000 > > raw: 0000000000000000 0000000000000000 00000001ffffffff > > 0000000000000000 > > > > The crash occurs for the same reason. > > > > In this case, on the really_probe() failure path, we are still clearing > > the DMA ops prior to releasing the device's managed memories. > > > > This patch fixes this issue by reordering the DMA ops teardown and the > > call to devres_release_all() on the failure path. > > > > Reported-by: Xiang Chen > > Tested-by: Xiang Chen > > Signed-off-by: John Garry So does this "fix" 376991db4b64? If so, should this be added to the patch and also backported to the stable trees? thanks, greg k-h