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=-6.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 44968C43214 for ; Wed, 25 Aug 2021 05:54:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 23FD361368 for ; Wed, 25 Aug 2021 05:54:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238139AbhHYFzF (ORCPT ); Wed, 25 Aug 2021 01:55:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:37952 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232420AbhHYFzD (ORCPT ); Wed, 25 Aug 2021 01:55:03 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1385561212; Wed, 25 Aug 2021 05:54:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1629870858; bh=wmjL9w2ZoY8OxCDTzWQ4QOrHwwaiCYA1Pt2DOMduG0Y=; h=References:From:To:Cc:Subject:Date:In-reply-to:From; b=aBBn6u7pGddSuvxDOJohavpgZxxIfIgfS7LFniKKR2eo7+4vZB4hZdceKOFODgjyX EcmfvBm87lNoAC9am4HGFbkLT6QJUOtxdMc5ma5QDF1cLMj1Kvr/h+FJW7mwHJGaZU mHI8mttyOUW9dJ6MD6CY1UYrap44XfNPlb+ioFa5bU4FkagrBNhrug6oGEO1Fm4ZrZ UUGNAG/jhvUsX3fHRJ2M8TFzZiShfF6o1U/N5CwXcP295sqatlteAeh6bgiWkOSOmd UCylXBd1ZvmNIYzziGDR5F3Y0uFszgfkC9JiysP/NcOMePEUExsTvFrdK75Mcb3EjR yp6ee5usIXkXA== References: <20210824201433.11385-1-ftoth@exalondelft.nl> <20210824201433.11385-2-ftoth@exalondelft.nl> User-agent: mu4e 1.6.4; emacs 27.2 From: Felipe Balbi To: Ferry Toth Cc: Greg Kroah-Hartman , Jerome Brunet , Ruslan Bilovol , Oded Gabbay , Cezary Rojewski , Mauro Carvalho Chehab , Pawel Laszczak , Jack Pham , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, linux-doc@vger.kernel.org, Jonathan Corbet , Lorenzo Colitti , Wesley Cheng , robh+dt@kernel.org, agross@kernel.org, bjorn.andersson@linaro.org, frowand.list@gmail.com, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, heikki.krogerus@linux.intel.com, Thinh Nguyen , Andy Shevchenko , Pavel Hofman , Ferry Toth Subject: Re: [PATCH v1 2/3] Revert "usb: gadget: f_uac2: add adaptive sync support for capture" Date: Wed, 25 Aug 2021 08:53:57 +0300 In-reply-to: <20210824201433.11385-2-ftoth@exalondelft.nl> Message-ID: <87r1ei5at8.fsf@kernel.org> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Ferry Toth writes: > This reverts commit 40c73b30546e759bedcec607fedc2d4be954508f. > > The commit is part of a series with commit > 24f779dac8f3efb9629adc0e486914d93dc45517 causing a BUG on dwc3 > hardware, at least on Intel Merrifield platform when configured > through configfs: > BUG: kernel NULL pointer dereference, address: 0000000000000008 > ... > RIP: 0010:dwc3_gadget_del_and_unmap_request+0x19/0xe0 > ... > Call Trace: > dwc3_remove_requests.constprop.0+0x12f/0x170 > __dwc3_gadget_ep_disable+0x7a/0x160 > dwc3_gadget_ep_disable+0x3d/0xd0 > usb_ep_disable+0x1c/0x70 > u_audio_stop_capture+0x79/0x120 [u_audio] > afunc_set_alt+0x73/0x80 [usb_f_uac2] > composite_setup+0x224/0x1b90 [libcomposite] > > Pavel's suggestion to add > `echo "adaptive" > functions/uac2.usb0/c_sync` to the configfs script > resolves the issue. > Thinh suggests "the crash is probably because of f_uac2 prematurely > freeing feedback request before its completion. usb_ep_dequeue() is > asynchronous. dwc2() may treat it as a synchronous call so you didn't > get a crash." > > Revert as this is a regression and the kernel shouldn't crash depending > on configuration parameters. > > Reported-by: Ferry Toth Signed-off-by? -- balbi