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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9F12C77B73 for ; Wed, 31 May 2023 13:10:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233203AbjEaNKT (ORCPT ); Wed, 31 May 2023 09:10:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235873AbjEaNKO (ORCPT ); Wed, 31 May 2023 09:10:14 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6BE5713E; Wed, 31 May 2023 06:10:06 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E7C9762861; Wed, 31 May 2023 13:10:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A8B0C433D2; Wed, 31 May 2023 13:10:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1685538605; bh=N7v6UdCdoRDaOMtpTdXXMBT2de0u9wjqumzPzRpdTAw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Wr+xtuxP/fN6kmb8aGSppryJP3huDhA21hKsAT3N8F9gvrVKbCQ0F7VJzgKL4cssQ DWwxG3Y5twq5W5vXGLpbJL+4m8CLRQPnqCDeayf1bGLEcWDZZsn/WUHmy/HAYWTHdm /A80iws/6gDkmrEB8MvL+qVRj06ibzBfIGO2xB+8= Date: Wed, 31 May 2023 14:10:02 +0100 From: Greg Kroah-Hartman To: Ricardo Ribalda Delgado Cc: Mathias Nyman , Mathias Nyman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Stephen Boyd Subject: Re: [PATCH] xhci: Do not create endpoint debugfs while holding the bandwidth mutex Message-ID: <2023053152-pegboard-oncoming-18ce@gregkh> References: <20230531-xhci-deadlock-v1-1-57780bff5124@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230531-xhci-deadlock-v1-1-57780bff5124@chromium.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 31, 2023 at 02:40:02PM +0200, Ricardo Ribalda Delgado wrote: > xhci_debugfs_create_endpoint needs to take the mm->mmap_sem, which is > not serialized with the hcd->bandwidth_mutex across the codebase. > > Without this patch a deadlock has been observed with the uvc driver at > the functions v4l2_mmap() and usb_set_interface(). > > Cc: Stephen Boyd " :(