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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 8C336C433DF for ; Wed, 24 Jun 2020 07:00:45 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 6873C206E2 for ; Wed, 24 Jun 2020 07:00:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="oaZVXDQC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6873C206E2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=amd-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 299706E7EC; Wed, 24 Jun 2020 07:00:41 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id F2DB66E45D; Wed, 24 Jun 2020 06:11:54 +0000 (UTC) Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 4D4E52078A; Wed, 24 Jun 2020 06:11:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592979114; bh=FM2tQ6JnRDJ6MT95go3QxanMU7ENKqsXWamZTn77iMQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=oaZVXDQCV0eH6RKo4otHpf4R2vf09cY258wolUgVQ3p6bBb79Q+33ZTw8GvhYp6Bc GhTwpdccP4md0FWDtSREbDvMxAOHmA+hH9bsIgdsdH9iGnbcYx0iwoCi4oz6lML39H EadDHyxFYBLhSAA/mpDr9os2kF1OZ6ECstS3ZU4Y= Date: Wed, 24 Jun 2020 08:11:53 +0200 From: Greg KH To: Andrey Grodzovsky Subject: Re: [PATCH v2 5/8] drm/amdgpu: Refactor sysfs removal Message-ID: <20200624061153.GA933050@kroah.com> References: <1592719388-13819-1-git-send-email-andrey.grodzovsky@amd.com> <1592719388-13819-6-git-send-email-andrey.grodzovsky@amd.com> <20200622095124.GE20149@phenom.ffwll.local> <20200622112139.GA3421602@kroah.com> <20200622164551.GA112181@kroah.com> <4787b2a9-e7bf-ea3c-02e9-484a4fcb4742@amd.com> <20200623060532.GB3818201@kroah.com> <090c5a35-3088-d6d0-dcaf-5ce5542a4298@amd.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <090c5a35-3088-d6d0-dcaf-5ce5542a4298@amd.com> X-Mailman-Approved-At: Wed, 24 Jun 2020 07:00:40 +0000 X-BeenThere: amd-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion list for AMD gfx List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: daniel.vetter@ffwll.ch, michel@daenzer.net, dri-devel@lists.freedesktop.org, ppaalanen@gmail.com, amd-gfx@lists.freedesktop.org, Daniel Vetter , ckoenig.leichtzumerken@gmail.com, alexdeucher@gmail.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: amd-gfx-bounces@lists.freedesktop.org Sender: "amd-gfx" On Tue, Jun 23, 2020 at 11:04:30PM -0400, Andrey Grodzovsky wrote: > > On 6/23/20 2:05 AM, Greg KH wrote: > > On Tue, Jun 23, 2020 at 12:51:00AM -0400, Andrey Grodzovsky wrote: > > > On 6/22/20 12:45 PM, Greg KH wrote: > > > > On Mon, Jun 22, 2020 at 12:07:25PM -0400, Andrey Grodzovsky wrote: > > > > > On 6/22/20 7:21 AM, Greg KH wrote: > > > > > > On Mon, Jun 22, 2020 at 11:51:24AM +0200, Daniel Vetter wrote: > > > > > > > On Sun, Jun 21, 2020 at 02:03:05AM -0400, Andrey Grodzovsky wrote: > > > > > > > > Track sysfs files in a list so they all can be removed during pci remove > > > > > > > > since otherwise their removal after that causes crash because parent > > > > > > > > folder was already removed during pci remove. > > > > > > Huh? That should not happen, do you have a backtrace of that crash? > > > > > 2 examples in the attached trace. > > > > Odd, how did you trigger these? > > > > > > By manually triggering PCI remove from sysfs > > > > > > cd /sys/bus/pci/devices/0000\:05\:00.0 && echo 1 > remove > > For some reason, I didn't think that video/drm devices could handle > > hot-remove like this. The "old" PCI hotplug specification explicitly > > said that video devices were not supported, has that changed? > > > > And this whole issue is probably tied to the larger issue that Daniel > > was asking me about, when it came to device lifetimes and the drm layer, > > so odds are we need to fix that up first before worrying about trying to > > support this crazy request, right? :) > > > > > > > [ 925.738225 < 0.188086>] BUG: kernel NULL pointer dereference, address: 0000000000000090 > > > > > [ 925.738232 < 0.000007>] #PF: supervisor read access in kernel mode > > > > > [ 925.738236 < 0.000004>] #PF: error_code(0x0000) - not-present page > > > > > [ 925.738240 < 0.000004>] PGD 0 P4D 0 > > > > > [ 925.738245 < 0.000005>] Oops: 0000 [#1] SMP PTI > > > > > [ 925.738249 < 0.000004>] CPU: 7 PID: 2547 Comm: amdgpu_test Tainted: G W OE 5.5.0-rc7-dev-kfd+ #50 > > > > > [ 925.738256 < 0.000007>] Hardware name: System manufacturer System Product Name/RAMPAGE IV FORMULA, BIOS 4804 12/30/2013 > > > > > [ 925.738266 < 0.000010>] RIP: 0010:kernfs_find_ns+0x18/0x110 > > > > > [ 925.738270 < 0.000004>] Code: a6 cf ff 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 41 57 41 56 49 89 f6 41 55 41 54 49 89 fd 55 53 49 89 d4 <0f> b7 af 90 00 00 00 8b 05 8f ee 6b 01 48 8b 5f 68 66 83 e5 20 41 > > > > > [ 925.738282 < 0.000012>] RSP: 0018:ffffad6d0118fb00 EFLAGS: 00010246 > > > > > [ 925.738287 < 0.000005>] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 2098a12076864b7e > > > > > [ 925.738292 < 0.000005>] RDX: 0000000000000000 RSI: ffffffffb6606b31 RDI: 0000000000000000 > > > > > [ 925.738297 < 0.000005>] RBP: ffffffffb6606b31 R08: ffffffffb5379d10 R09: 0000000000000000 > > > > > [ 925.738302 < 0.000005>] R10: ffffad6d0118fb38 R11: ffff9a75f64820a8 R12: 0000000000000000 > > > > > [ 925.738307 < 0.000005>] R13: 0000000000000000 R14: ffffffffb6606b31 R15: ffff9a7612b06130 > > > > > [ 925.738313 < 0.000006>] FS: 00007f3eca4e8700(0000) GS:ffff9a763dbc0000(0000) knlGS:0000000000000000 > > > > > [ 925.738319 < 0.000006>] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > > > [ 925.738323 < 0.000004>] CR2: 0000000000000090 CR3: 0000000035e5a005 CR4: 00000000000606e0 > > > > > [ 925.738329 < 0.000006>] Call Trace: > > > > > [ 925.738334 < 0.000005>] kernfs_find_and_get_ns+0x2e/0x50 > > > > > [ 925.738339 < 0.000005>] sysfs_remove_group+0x25/0x80 > > > > > [ 925.738344 < 0.000005>] sysfs_remove_groups+0x29/0x40 > > > > > [ 925.738350 < 0.000006>] free_msi_irqs+0xf5/0x190 > > > > > [ 925.738354 < 0.000004>] pci_disable_msi+0xe9/0x120 > > > > So the PCI core is trying to clean up attributes that it had registered, > > > > which is fine. But we can't seem to find the attributes? Were they > > > > already removed somewhere else? > > > > > > > > that's odd. > > > > > > Yes, as i pointed above i am emulating device remove from sysfs and this > > > triggers pci device remove sequence and as part of that my specific device > > > folder (05:00.0) is removed from the sysfs tree. > > But why are things being removed twice? > > > Not sure I understand what removed twice ? I remove only once per sysfs attribute. This code path shows that the kernel is trying to remove a file that is not present, so someone removed it already... thanks, gre k-h _______________________________________________ amd-gfx mailing list amd-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/amd-gfx