linux-kernel - [PATCH v4 0/3] fix runtime PM for SD card readers

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210628133412.1172068-1-martin.kepplinger@puri.sm>
Date:   Mon, 28 Jun 2021 15:34:09 +0200
From:   Martin Kepplinger <martin.kepplinger@...i.sm>
To:     martin.kepplinger@...i.sm
Cc:     bvanassche@....org, jejb@...ux.ibm.com,
        linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
        linux-scsi@...r.kernel.org, martin.petersen@...cle.com,
        stern@...land.harvard.edu
Subject: [PATCH v4 0/3] fix runtime PM for SD card readers

hi,

(According to Alan Stern, "as far as I know, all") SD card readers send
MEDIA_CHANGED unit attention notification on (runtime) resume. We cannot
use runtime PM with these devices as I/O always fails in that case.

This fixes runtime PM for SD cardreaders. I'd appreciate any feedback.

To enable runtime PM for an SD cardreader number 0:0:0:0, do:
    
echo 0 > /sys/module/block/parameters/events_dfl_poll_msecs
echo 1000 > /sys/bus/scsi/devices/0:0:0:0/power/autosuspend_delay_ms
echo auto > /sys/bus/scsi/devices/0:0:0:0/power/control

thank you,
                           martin

revision history
----------------
v4: (thank you Bart and Alan)
* send SENSE REQUEST in sd instead of adding a global scsi error flag.

v3: (thank you Bart)
 * create a new BLIST entry to mark affected devices instead of the
   sysfs module parameter for sd only. still, only sd implements handling
   the flag for now.
 * cc linux-pm list
https://lore.kernel.org/linux-scsi/20210328102531.1114535-1-martin.kepplinger@puri.sm/

v2:
https://lore.kernel.org/linux-scsi/20210112093329.3639-1-martin.kepplinger@puri.sm/
 * move module parameter to sd
 * add Documentation
v1:
https://lore.kernel.org/linux-scsi/20210111152029.28426-1-martin.kepplinger@puri.sm/T/
For the full background, the discussion started in June 2020 here:
https://lore.kernel.org/linux-scsi/20200623111018.31954-1-martin.kepplinger@puri.sm/


Martin Kepplinger (3):
  scsi: devinfo: add new flag BLIST_MEDIA_CHANGE
  scsi: sd: send REQUEST SENSE for BLIST_MEDIA_CHANGE devices in
    runtime_resume()
  scsi: devinfo: add BLIST_MEDIA_CHANGE for Ultra HS-SD/MMC usb
    cardreaders

 drivers/scsi/scsi_devinfo.c |  1 +
 drivers/scsi/sd.c           | 37 ++++++++++++++++++++++++++++++++++++-
 include/scsi/scsi_devinfo.h |  6 +++---
 3 files changed, 40 insertions(+), 4 deletions(-)

-- 
2.30.2