From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [PATCH RESEND^2] sd: fix infinite kernel/udev loop on non-removable Medium Not Present Date: Fri, 26 Apr 2013 10:10:31 -0700 Message-ID: <20130426171031.GA29600@kroah.com> References: <1366994373-13324-1-git-send-email-steve@digidescorp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pb0-f48.google.com ([209.85.160.48]:49509 "EHLO mail-pb0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754092Ab3DZRKe (ORCPT ); Fri, 26 Apr 2013 13:10:34 -0400 Received: by mail-pb0-f48.google.com with SMTP id wy7so174463pbc.21 for ; Fri, 26 Apr 2013 10:10:34 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1366994373-13324-1-git-send-email-steve@digidescorp.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Steven J. Magnani" Cc: "James E.J. Bottomley" , Tejun Heo , linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, stable@vger.kernel.org On Fri, Apr 26, 2013 at 11:39:33AM -0500, Steven J. Magnani wrote: > Commit eface65c336eff420d70beb0fb6787a732e05ffb (2.6.38) altered > set_media_not_present() in a way that prevents the sd driver from > remembering that a non-removable device has reported "Medium Not Present". > This condition can occur on hotplug of a (i.e.) USB Mass Storage device > whose medium is offline due to an unrecoverable controller error, > but which is otherwise capable of SCSI communication (to download new > microcode, etc.). > > Under these conditions, the changed code results in an infinite loop > between the kernel and udevd. When udevd attempts to open the device > in response to a change notification, a SCSI "Medium Not Present" error > occurs which causes the kernel to signal another change. The cycle > repeats until the device is unplugged, resulting in udevd consuming ever- > increasing amounts of CPU and virtual memory. > > Resolve this by remembering "media not present" whether the device has > declared itself "removable" or not. > > Signed-off-by: Steven J. Magnani > --- This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read Documentation/stable_kernel_rules.txt for how to do this properly.