Re: kern/52147: deadlock when booting from USB disk

[christos%zoulas.com@localhost (Christos Zoulas)]

The following reply was made to PR kern/52147; it has been noted by GNATS.

From: christos%zoulas.com@localhost (Christos Zoulas)
To: =?UTF-8?B?SmFyb23DrXIgRG9sZcSNZWs=?= <jaromir.dolecek%gmail.com@localhost>
Cc: gnats-bugs%netbsd.org@localhost, Jaromir Dolecek <jdolecek%netbsd.org@localhost>, 
	gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost, 
	Michael van Elst <mlelstv%serpens.de@localhost>
Subject: Re: kern/52147: deadlock when booting from USB disk
Date: Wed, 12 Apr 2017 14:25:13 -0400

 On Apr 12,  8:08pm, jaromir.dolecek%gmail.com@localhost (=?UTF-8?B?SmFyb23DrXIgRG9sZcSNZWs=?=) wrote:
 -- Subject: Re: kern/52147: deadlock when booting from USB disk
 
 | Yes, the offending MODE SENSE was silenced, it doesn't try to print
 | anything out. But it could easily be reintroduced if we add there
 | something else, which would cause the same problem again. Having
 | something inherently deadlocking is quite dangerous.
 | 
 | Given that scsiverbose is only cosmetic and completely optional (code
 | prints some relevant info out even without it), I think it makes sense
 | to leave it up to explicit user action to have it loaded.
 
 I think it is better to just fix it not to deadlock, this is why I was
 asking for a stack trace... This has never been a problem so far; it
 got introduced by adding the mode-sense code. Yes, I agree it could
 be re-introduced again, but manually loading modules goes against the
 principle of having module loading/unloading be seamless and not noticed
 by the user.
 
 christos