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 6E59DC433EF for ; Thu, 7 Jul 2022 08:04:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234907AbiGGIEg (ORCPT ); Thu, 7 Jul 2022 04:04:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232120AbiGGIEe (ORCPT ); Thu, 7 Jul 2022 04:04:34 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C20F25C5; Thu, 7 Jul 2022 01:04:33 -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 ams.source.kernel.org (Postfix) with ESMTPS id A02ADB81F50; Thu, 7 Jul 2022 08:04:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3100C341C8; Thu, 7 Jul 2022 08:04:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1657181070; bh=i3ubyFnOD3zhjC1AIUILsyZXAyE/N1coKv+uqBVa8Z0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=xXCqNLAfXYa38ck54PvLEFvRVCNtD/7EEsqBmJZU/dy5P8udEd3TfpR8pDo79XQKq UKxBKT4lfdaqth7MXIz5qMOQJV9ag0Tmm7vMq0yN64MK8GuLDSalGxiI9nrLFqRJCE UkSEYCLninFNnTT8zdP4zQQIx4738L7Bpwpt7mhk= Date: Thu, 7 Jul 2022 10:04:27 +0200 From: Greg KH To: Tetsuo Handa Cc: Oliver Neukum , "Rafael J. Wysocki" , Wedson Almeida Filho , Len Brown , Pavel Machek , Arnd Bergmann , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Dmitry Vyukov , Arjan van de Ven Subject: Re: [PATCH] char: misc: make misc_open() and misc_register() killable Message-ID: References: <617f64e3-74c8-f98b-3430-bd476867e483@I-love.SAKURA.ne.jp> <5665ccb2-b92b-9e1f-8bb5-a950986450ec@I-love.SAKURA.ne.jp> <064bbe2a-c18e-203e-9e01-b32fe9baa390@I-love.SAKURA.ne.jp> <7ddb25ff-60e5-75be-8080-2a7465cca68c@I-love.SAKURA.ne.jp> <815866b5-842e-4829-5ed8-26a5f1e856a4@suse.com> <22c61a75-8140-c62d-ffe0-efd6e9fa38ee@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <22c61a75-8140-c62d-ffe0-efd6e9fa38ee@I-love.SAKURA.ne.jp> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 07, 2022 at 02:06:38PM +0900, Tetsuo Handa wrote: > On 2022/07/06 20:04, Oliver Neukum wrote: > > > > > > On 06.07.22 12:26, Tetsuo Handa wrote: > >> On 2022/07/06 15:34, Greg KH wrote: > >>> On Wed, Jul 06, 2022 at 03:21:15PM +0900, Tetsuo Handa wrote: > >>>> How should we fix this problem? > >>> > >>> We can decrease the timeout in usb_stor_msg_common(). I imagine that if > >>> that timeout is ever hit in this sequence, then all will recover, right? > > > > Not really. The timeout there is supposed to come from the SCSI layer > > in the general case. > > I couldn't catch. usb_stor_msg_common() belongs to USB subsystem, doesn't it? > > How does SCSI layer matter here? > Does USB storage device shows up as if SCSI disk (e.g. /dev/sdb) relevant? Yes. USB storage is a very tiny wrapper around the whole SCSI protocol, it is a SCSI disk for all all intensive purposes. thanks, greg k-h