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Date: Wed, 28 Mar 2018 10:26:57 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] proc: register filesystem last
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On Wed, Mar 28, 2018 at 05:48:23AM +0100, Al Viro wrote:
> On Sat, Mar 10, 2018 at 03:06:34AM +0300, Alexey Dobriyan wrote:
> > On Fri, Mar 09, 2018 at 02:49:38PM -0800, Andrew Morton wrote:
> > > On Sat, 10 Mar 2018 01:27:09 +0300 Alexey Dobriyan <adobriyan@gmail.com> wrote:
> > > 
> > > > As soon as register_filesystem() exits, filesystem can be mounted.
> > > > It is better to present fully operational /proc.
> > > > 
> > > > Of course it doesn't matter because /proc is not modular
> > > > but do it anyway.
> > > > 
> > > > Drop error check, it should be handled by panicking.
> > > 
> > > So... shouldn't we add a call to panic()?
> > 
> > via FS_PANIC flag, yes. I have a patch somewhere.
> > There are 104 filesystems ATM, some internal, some not.
> > Some modular, some not.
> 
> You do realize that the only case when register_filesystem() fails is
> "another driver has already registered filesystem type with the same
> name"?  Is there *ever* a case when
> 	* you could expect that to happen and
> 	* panic would be a sane response?

It is for standartizing all those error checks in init sequence by
removing them. Modules won't have FS_PANIC.