Re: kern/53928: modules/t_builtin:disable test case randomly fails

[Paul Goyette <paul%whooppee.com@localhost>]

The following reply was made to PR kern/53928; it has been noted by GNATS.

From: Paul Goyette <paul%whooppee.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/53928: modules/t_builtin:disable test case randomly fails
Date: Wed, 30 Jan 2019 20:18:07 +0800 (PST)

 I rebuilt a local librump with kern.module.verbose enabled and ran the
 test case with RUMP_VERBOSE=1 defined.  This resulted in the following:
 
 ...
 [   1.0000090] root file system type: rumpfs
 [   1.0000090] kern.module.path=/stand/amd64/8.99.32/modules
 [   1.0200090] DEBUG: module: unload requested for 'kernfs' (TRUE)
 [   1.0200090] DEBUG: module: cannot unload module `kernfs' error=16
 
 The particular "cannot unload module" error is generated when there
 is an error returned from the module's MODULE_CMD_FINI routine.
 
 So, the problem here would appear to be vfs_detach() returning EBUSY
 when trying to unload the module.
 
 Since this is not strictly speaking a module problem, I'm going to
 reassign this PR back to kern-bug-people.  Someone who knows about
 vfs_detach() can determine why it sometimes fails.
 
 
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