id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	field_blocks	field_dependson	field_seealso
480	VFS deadlocks when FS calles VFS operation (namespace_rwlock)	Zdenek Bouska	Jakub Jermář	"Jakub on mailing list:

The solution with a global namespace lock traded flexibility for
simplicity. When your fs implementation uses the VFS input interface
(e.g. via libc wrappers) it always creates a possibility for a deadlock
because it creates a loop and there may always be some locks taken or
resources consumed along the codepaths that form the loop. The more
operations this loop involves, the more likely it is that there will be
a deadlock.

We should probably change this behavior and remove this inflexibility as
it is a potential security problem at the same time; if we want to have
unprivileged file systems (or just privileged less than VFS), VFS needs
to be able to gracefully survive someone's attempt to do crazy stuff.

http://lists.modry.cz/cgi-bin/private/helenos-devel/2012-August/008685.html
http://lists.modry.cz/cgi-bin/private/helenos-devel/2012-August/008691.html
http://lists.modry.cz/cgi-bin/private/helenos-devel/2012-August/008692.html
http://lists.modry.cz/cgi-bin/private/helenos-devel/2012-August/008693.html"	enhancement	new	major		helenos/srv/vfs	mainline