[dm-devel] Re: [PATCH 7/9] scsi_dh: Add support for SDEV_PASSIVE

[James Bottomley]

On Mon, 2008-02-04 at 12:15 -0800, Chandra Seetharaman wrote:
> On Mon, 2008-02-04 at 12:58 -0600, James Bottomley wrote:
> > On Wed, 2008-01-23 at 16:32 -0800, Chandra Seetharaman wrote:
> > > Subject: scsi_dh: Add support for SDEV_PASSIVE
> > > 
> > > From: Chandra Seetharaman <sekharan at us.ibm.com>
> > > 
> > > This patch adds a new device state SDEV_PASSIVE, to correspond to the
> > > passive side access of an active/passive multipathed device.
> > 
> > Really, no; this isn't right.  The state field of a SCSI device is for
> > the SCSI state model.  Passive might be a valid device mapper state, but
> 
> Hi James,
> 
> It is not the "device mapper state", it is the state of the device
> itself. These devices have active/passive paths, the passive paths will
> be represented by SDEV_PASSIVE device state in SCSI.

Yes, it is .. you're killing commands on the basis of being in this
state, which nothing in SCSI ever sets.

A proper return from a passive path is the SCSI standard NOT_READY
LOGICAL UNIT NOT READY, INITIALIZING COMMAND REQUIRED.  We expect to see
this, not the command being killed.

James