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=-16.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 0F1DFC432C3 for ; Mon, 2 Dec 2019 21:20:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C968D20675 for ; Mon, 2 Dec 2019 21:20:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="YjS2Bjfg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726060AbfLBVUA (ORCPT ); Mon, 2 Dec 2019 16:20:00 -0500 Received: from mail-ot1-f67.google.com ([209.85.210.67]:45517 "EHLO mail-ot1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726024AbfLBVUA (ORCPT ); Mon, 2 Dec 2019 16:20:00 -0500 Received: by mail-ot1-f67.google.com with SMTP id 59so848703otp.12 for ; Mon, 02 Dec 2019 13:19:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=n2uB+/TzMRfuXTzQ7bU449yX1FcyufRJbPoSOJ+c3b0=; b=YjS2BjfgIad+yr/+k7u+m/tqwJlSMc306BJTD1R5TazsQg2W7cfJ9FfJsaHT4l7CQO jh1+EvC5J9CoSXHl14gwyx/ChCj3zGXoNYgOGCvs0mUTuuKDbNHUWXeFgZzuvnEOtbpD ZzXIjnObv/CGwdOK/eDZTrsI9E/RcXoe41Ha4QozYVBFL6jFmAzqFHW4lLt27jb6Da9O cEpHFCqT9zjgAqGnaYrn0jAUBNCxXDn+qhlswz+DhyfbIZ9NsOjVBJ01N2r++1D0zyLB 8HHSB6jb+5TX8T0Ma57wQTefq25AllLETsyab1+fAsPmRcB8XnrzpN4pMnLoxkTCmoIu sVKQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=n2uB+/TzMRfuXTzQ7bU449yX1FcyufRJbPoSOJ+c3b0=; b=unvMN+t1Euo2BCYH7LJF+M9NOMDAR74UacPRBqxECJOTUQA9LgwD5i0vxFW9eFLEPc WHG7roOHo9e3NU8VafP3nm1TlY5OObFTK9k0ceeLC56CX2Aknp8uVbndOKBapDdZXzI+ 0mMXtcGSPIBpQ8b3ExJ75hYkQ9y4MJJUs6i3m7g0+23vzV2GMeZYmzakl3kZYhR7xovA glcxrHqDDyZ9eBPMuSFIyXfIaeGooAoLWyx/yIqskxjGEJ6knEtBpWCcRcQFAmrJerDg E4ULhmHP4a0I0hxZrYWkXwJEV+pjPY59XSk6dPvm5MezpxXVkX4rE8nVubbju1FDqusB pWPg== X-Gm-Message-State: APjAAAWi/MSRX30kpfapa3da6rPEtSW7mTTgKOXG5Lgr5k9M3ijfsXTt Hjw2P/2Jzm9G7AD6zCC0fRLB5hperGEZFdP63Os03w== X-Google-Smtp-Source: APXvYqykoqTX4clV94B0+24/eTdmMzmP3M1dBPtTZhuddmIhYXFIEk7t4XfCzz/I6yQtBNdvOPcm4xoLtzhy9BkNS10= X-Received: by 2002:a9d:648f:: with SMTP id g15mr844588otl.195.1575321598246; Mon, 02 Dec 2019 13:19:58 -0800 (PST) MIME-Version: 1.0 References: <20191201150015.GC18573@shao2-debian> In-Reply-To: <20191201150015.GC18573@shao2-debian> From: Saravana Kannan Date: Mon, 2 Dec 2019 13:19:22 -0800 Message-ID: Subject: Re: 5e6669387e ("of/platform: Pause/resume sync state during init .."): [ 3.192726] WARNING: CPU: 1 PID: 1 at drivers/base/core.c:688 device_links_supplier_sync_state_resume To: Frank Rowand , Rob Herring Cc: Greg Kroah-Hartman , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , LKML , LKP , kernel test robot Content-Type: text/plain; charset="UTF-8" Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Sun, Dec 1, 2019 at 7:00 AM kernel test robot wrote: > > Greetings, > > 0day kernel testing robot got the below dmesg and the first bad commit is > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > > commit 5e6669387e2287f25f09fd0abd279dae104cfa7e > Author: Saravana Kannan > AuthorDate: Wed Sep 4 14:11:24 2019 -0700 > Commit: Greg Kroah-Hartman > CommitDate: Fri Oct 4 17:30:19 2019 +0200 > > of/platform: Pause/resume sync state during init and of_platform_populate() > > When all the top level devices are populated from DT during kernel > init, the supplier devices could be added and probed before the > consumer devices are added and linked to the suppliers. To avoid the > sync_state() callback from being called prematurely, pause the > sync_state() callbacks before populating the devices and resume them > at late_initcall_sync(). > > Similarly, when children devices are populated from a module using > of_platform_populate(), there could be supplier-consumer dependencies > between the children devices that are populated. To avoid the same > problem with sync_state() being called prematurely, pause and resume > sync_state() callbacks across of_platform_populate(). > > Signed-off-by: Saravana Kannan > Link: https://lore.kernel.org/r/20190904211126.47518-6-saravanak@google.com > Signed-off-by: Greg Kroah-Hartman > > fc5a251d0f driver core: Add sync_state driver/bus callback > 5e6669387e of/platform: Pause/resume sync state during init and of_platform_populate() > 81b6b96475 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux; tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping > +-------------------------------------------------------------------------+------------+------------+------------+ > | | fc5a251d0f | 5e6669387e | 81b6b96475 | > +-------------------------------------------------------------------------+------------+------------+------------+ > | boot_successes | 30 | 0 | 0 | > | boot_failures | 1 | 11 | 22 | > | Oops:#[##] | 1 | | | > | EIP:unmap_vmas | 1 | | | > | PANIC:double_fault | 1 | | | > | Kernel_panic-not_syncing:Fatal_exception | 1 | | | > | WARNING:at_drivers/base/core.c:#device_links_supplier_sync_state_resume | 0 | 11 | 22 | > | EIP:device_links_supplier_sync_state_resume | 0 | 11 | 22 | > +-------------------------------------------------------------------------+------------+------------+------------+ > > If you fix the issue, kindly add following tag > Reported-by: kernel test robot > > [ 3.186107] OF: /testcase-data/phandle-tests/consumer-b: #phandle-cells = 2 found -1 > [ 3.188595] platform testcase-data:testcase-device2: IRQ index 0 not found > [ 3.191047] ### dt-test ### end of unittest - 199 passed, 0 failed > [ 3.191932] ------------[ cut here ]------------ > [ 3.192571] Unmatched sync_state pause/resume! > [ 3.192726] WARNING: CPU: 1 PID: 1 at drivers/base/core.c:688 device_links_supplier_sync_state_resume+0x27/0xc0 > [ 3.195084] Modules linked in: > [ 3.195494] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G T 5.4.0-rc1-00005-g5e6669387e228 #1 > [ 3.196674] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 > [ 3.197693] EIP: device_links_supplier_sync_state_resume+0x27/0xc0 > [ 3.198680] Code: 00 00 00 3e 8d 74 26 00 57 56 31 d2 53 b8 a0 d0 d9 c1 e8 6c b6 38 00 a1 e4 d0 d9 c1 85 c0 75 13 68 84 ba c4 c1 e8 29 30 b1 ff <0f> 0b 58 eb 7f 8d 74 26 00 83 e8 01 85 c0 a3 e4 d0 d9 c1 75 6f 8b > [ 3.201560] EAX: 00000022 EBX: 00000000 ECX: 00000000 EDX: 00000000 > [ 3.202466] ESI: 000001ab EDI: c02c7f80 EBP: c1e87d27 ESP: c02c7f20 > [ 3.203301] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010282 > [ 3.204258] CR0: 80050033 CR2: bfa1bf98 CR3: 01f28000 CR4: 00140690 > [ 3.205022] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 > [ 3.205919] DR6: fffe0ff0 DR7: 00000400 > [ 3.206529] Call Trace: > [ 3.207011] ? of_platform_sync_state_init+0x13/0x16 > [ 3.207719] ? do_one_initcall+0xda/0x260 > [ 3.208247] ? kernel_init_freeable+0x110/0x197 > [ 3.208906] ? rest_init+0x120/0x120 > [ 3.209369] ? kernel_init+0xa/0x100 > [ 3.209775] ? ret_from_fork+0x19/0x24 > [ 3.210283] ---[ end trace 81d0f2d2ee65199b ]--- > [ 3.210955] ALSA device list: Rob/Frank, This seems to be an issue with the unit test code not properly cleaning up the state after it's done. Specifically, unittest_data_add() setting up of_root on systems where there's no device tree (of_root == NULL). It doesn't clean up of_root after the tests are done. This affects the of_have_populated_dt() API that in turn affects calls to device_links_supplier_sync_state_pause/resume(). I think unittests shouldn't affect the of_have_populated_dt() API. I was looking into writing a unittest patch to fix this, but I don't know enough about the FDT parsing code to make sure I don't leak any memory or free stuff that's in use. I'm not sure I can simply set of_root = NULL if it was NULL before the unittest started. Let me know how I should proceed or if you plan to write up a patch for this. Thanks, Saravana