From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH v3 1/6] [SCSI] Add a kernel config option for enhanced Unit Attention support Date: Wed, 19 Jun 2013 18:35:12 +0000 Message-ID: <1371666911.2409.72.camel@dabdike> References: <1371663761-22481-1-git-send-email-emilne@redhat.com> <1371663761-22481-2-git-send-email-emilne@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from mx2.parallels.com ([199.115.105.18]:53663 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757377Ab3FSSfO convert rfc822-to-8bit (ORCPT ); Wed, 19 Jun 2013 14:35:14 -0400 In-Reply-To: <1371663761-22481-2-git-send-email-emilne@redhat.com> Content-Language: en-US Content-ID: <1683DA38A067FB4FAB4F027FB729A4DA@sw.swsoft.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Ewan D. Milne" Cc: "linux-scsi@vger.kernel.org" , "rwheeler@redhat.com" On Wed, 2013-06-19 at 13:42 -0400, Ewan D. Milne wrote: > From: "Ewan D. Milne" > > Added CONFIG_SCSI_ENHANCED_UA kernel config option to enable changes > in the SCSI mid-layer which detect and report certain Unit Attention > conditions reported by devices. These changes are primarily useful > when storage arrays that can be reconfigured are being used, so the > config option would normally not be used unless it was needed. > > Signed-off-by: Ewan D. Milne > --- > drivers/scsi/Kconfig | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig > index e955978..5d1e614 100644 > --- a/drivers/scsi/Kconfig > +++ b/drivers/scsi/Kconfig > @@ -280,6 +280,18 @@ config SCSI_WAIT_SCAN > # disabling it, whereas people who accidentally switch it off may wonder why > # their mkinitrd gets into trouble. > > +config SCSI_ENHANCED_UA > + bool "Enhanced SCSI Unit Attention handling" > + depends on SCSI > + help > + Certain SCSI devices report changes via a UNIT ATTENTION code. > + (For example, the addition or removal of LUNs from a target, or > + changing the number of logical blocks on a LUN.) This option > + enables reporting of these changes via udev events, so that the > + device can be rescanned to find out what has changed. This is > + primarily useful when storage arrays that can be reconfigured > + are attached to the system, otherwise you can say N here. > + I don't think we need this. If we're going to do device events, we should do it unconditionally. The recourse for not wanting them is not listening for them. That way we don't have two separate config branches to maintain, one of which will surely bitrot. James