From patchwork Tue Jan 12 09:33:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Kepplinger X-Patchwork-Id: 12012907 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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 20382C4332E for ; Tue, 12 Jan 2021 09:35:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0A0E23100 for ; Tue, 12 Jan 2021 09:35:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392656AbhALJfA (ORCPT ); Tue, 12 Jan 2021 04:35:00 -0500 Received: from comms.puri.sm ([159.203.221.185]:33640 "EHLO comms.puri.sm" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731123AbhALJe7 (ORCPT ); Tue, 12 Jan 2021 04:34:59 -0500 Received: from localhost (localhost [127.0.0.1]) by comms.puri.sm (Postfix) with ESMTP id 8BBC8DFDE2; Tue, 12 Jan 2021 01:33:49 -0800 (PST) Received: from comms.puri.sm ([127.0.0.1]) by localhost (comms.puri.sm [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id bBp79AYO0gXz; Tue, 12 Jan 2021 01:33:48 -0800 (PST) From: Martin Kepplinger To: jejb@linux.ibm.com, martin.petersen@oracle.com, stern@rowland.harvard.edu, bvanassche@acm.org Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Martin Kepplinger Subject: [PATCH v2 0/3] scsi: add runtime PM workaround for SD cardreaders Date: Tue, 12 Jan 2021 10:33:26 +0100 Message-Id: <20210112093329.3639-1-martin.kepplinger@puri.sm> Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org revision history ---------------- v2: * move module parameter to sd * add Documentation v1: https://lore.kernel.org/linux-scsi/20210111152029.28426-1-martin.kepplinger@puri.sm/T/#t hi, In short: there are SD cardreaders that send MEDIA_CHANGED on runtime resume. We cannot use runtime PM with these devices as I/O basically always fails. I'd like to discuss a way to fix this or at least allow users to work around this problem: For the full background, the discussion started in June 2020 here: https://lore.kernel.org/linux-scsi/20200623111018.31954-1-martin.kepplinger@puri.sm/ and I sent the first of these patches in August, as a reference: https://lore.kernel.org/linux-scsi/20200824190400.12339-1-martin.kepplinger@puri.sm/ so this is where I'm following up on. I'm not sure whether maintaining an in-kernel quirk for specific devices makes sense so here I suggest adding a userspace knob. This way there's at least a chance to use runtime PM for sd cardreaders that send MEDIA_CHANGED. I'd appreciate any feedback. Martin Kepplinger (3): scsi: add expecting_media_change flag to error path scsi: sd: add ignore_resume_medium_changed disk setting scsi: sd: Documentation: describe ignore_resume_medium_changed Documentation/scsi/sd-parameters.rst | 14 ++++++++ drivers/scsi/scsi_error.c | 36 +++++++++++++++++--- drivers/scsi/sd.c | 50 +++++++++++++++++++++++++++- drivers/scsi/sd.h | 1 + include/scsi/scsi_device.h | 1 + 5 files changed, 96 insertions(+), 6 deletions(-)