usb/140477: [umass] [patch] allow boot-time attachment of daX devices to GEOM_ELI

[Eygene Ryabinkin]

The following reply was made to PR usb/140477; it has been noted by GNATS.

From: Eygene Ryabinkin <rea-fbsd at codelabs.ru>
To: "Bjoern A. Zeeb" <bzeeb-lists at lists.zabbadoz.net>
Cc: bug-followup at FreeBSD.org
Subject: Re: usb/140477: [umass] [patch] allow boot-time attachment of daX
 devices to GEOM_ELI
Date: Thu, 12 Nov 2009 12:11:17 +0300

 Bjoern, good day.
 
 Thu, Nov 12, 2009 at 07:28:03AM +0000, Bjoern A. Zeeb wrote:
 > has this changed recently, that it no longer works?  I seem to
 > remember that it had perfectly worked before this year.
 
 Yes, it used to work with up to 7.<anything>.  But it seems that with
 the new USB stack we have asynchronous discovery and attachment, so
 other subsystems are started when this process isn't yet fully
 completed, so root mount is getting "closer" and, for my case, root
 mount typically waits only for the completion of USB tasks.
 
 My gut feeling is that the device discovery prior to the USBv2 was
 done synchronously, but with USBv2 kernel use async callbacks.  Though,
 I may be wrong in this judgement.
 
 You can try it yourself -- plugged USB stick with geli volume that is
 marked as attach-on-boot should show the current behaviour.
 -- 
 Eygene
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