linux-hotplug.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Tejun Heo <tj@kernel.org>
To: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: linux-scsi@vger.kernel.org, kay.sievers@vrfy.org,
	maggu2810@googlemail.com, linux-hotplug@vger.kernel.org
Subject: Re: [PATCH SCSI] sr: check_events() ignore GET_EVENT when TUR says
Date: Wed, 20 Jul 2011 16:33:08 +0000	[thread overview]
Message-ID: <20110720163308.GC9924@mtj.dyndns.org> (raw)
In-Reply-To: <20110630130348.GQ3386@htj.dyndns.org>

On Thu, Jun 30, 2011 at 03:03:48PM +0200, Tejun Heo wrote:
> From: Kay Sievers <kay.sievers@vrfy.org>
> 
> Some broken devices indicates that media has changed on every
> GET_EVENT_STATUS_NOTIFICATION.  This translates into MEDIA_CHANGE
> uevent on every open() which lets udev run into a loop.
> 
> Verify GET_EVENT result against TUR and if it generates spurious
> events for several times in a row, ignore the GET_EVENT events, and
> trust only the TUR status.
> 
> This is the log of a USB stick with a (broken) fake CDROM drive:
> 
>  scsi 5:0:0:0: Direct-Access     SanDisk  U3 Cruzer Micro  8.02 PQ: 0 ANSI: 0 CCS
>  sd 5:0:0:0: Attached scsi generic sg3 type 0
>  scsi 5:0:0:1: CD-ROM            SanDisk  U3 Cruzer Micro  8.02 PQ: 0 ANSI: 0
>  sd 5:0:0:0: [sdb] Attached SCSI removable disk
>  sr2: scsi3-mmc drive: 48x/48x tray
>  sr 5:0:0:1: Attached scsi CD-ROM sr2
>  sr 5:0:0:1: Attached scsi generic sg4 type 5
>  sr2: GET_EVENT and TUR disagree continuously, suppress GET_EVENT events
>  sd 5:0:0:0: [sdb] 31777279 512-byte logical blocks: (16.2 GB/15.1 GiB)
>  sd 5:0:0:0: [sdb] No Caching mode page present
>  sd 5:0:0:0: [sdb] Assuming drive cache: write through
>  sd 5:0:0:0: [sdb] No Caching mode page present
>  sd 5:0:0:0: [sdb] Assuming drive cache: write through
>  sdb: sdb1
> 
> -tj: Updated to consider only spurious GET_EVENT events among
>      different types of disagreement and allow using TUR for kernel
>      event polling after GET_EVENT is ignored.
> 
> Reported-By: Markus Rathgeb maggu2810@googlemail.com
> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
> Signed-off-by: Tejun Heo <tj@kernel.org>
> Cc: stable@kernel.org	# >= v2.6.38, fixes udev busy looping w/ certain devices

James, ping.

-- 
tejun

  reply	other threads:[~2011-07-20 16:33 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-30 13:03 [PATCH SCSI] sr: check_events() ignore GET_EVENT when TUR says Tejun Heo
2011-07-20 16:33 ` Tejun Heo [this message]
2011-07-20 16:42   ` [PATCH SCSI] sr: check_events() ignore GET_EVENT when TUR says otherwise Kay Sievers
2011-07-20 16:45     ` [PATCH SCSI] sr: check_events() ignore GET_EVENT when TUR says James Bottomley
2012-07-30 19:06       ` [PATCH SCSI] sr: check_events() ignore GET_EVENT when TUR says otherwise Markus Rathgeb
2012-07-30 19:41         ` Kay Sievers
2012-07-30 20:28           ` Markus Rathgeb

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20110720163308.GC9924@mtj.dyndns.org \
    --to=tj@kernel.org \
    --cc=James.Bottomley@HansenPartnership.com \
    --cc=kay.sievers@vrfy.org \
    --cc=linux-hotplug@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=maggu2810@googlemail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).