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From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 01/13] devpts: Teach /dev/ptmx to find the associated
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To: Linus Torvalds <torvalds@linux-foundation.org>,
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Date: Tue, 12 Apr 2016 12:07:45 -0700
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On 04/12/16 11:12, Linus Torvalds wrote:
>
> So what I want to happen is to "just make /dev/ptmx work".  Get rid of
> the broken "single instance" crap. The only reason it exists is
> exactly because /dev/ptmx does not work.
>
> I think the current situation is completely and utterly broken. We
> should never have done what we did. I want to *fix* the kernel, not
> add random new magic crap.
>

Agreed.  As far as I'm concerned, there seem to be two realistic 
variants, talking semantically as opposed to implementation-wise:


1. Change the default mode of /dev/pts/ptmx to default to 0666, and make 
/dev/ptmx have the effective semantics of the symlink which userspace 
and userdev/devramfs should have provided all along.

2. Make /dev/ptmx simply look up the pts superblock from its path and 
then act like /dev/pts/ptmx.  In that case we can probably remove the 
ptmx device node unless the ptmxmode mount option is given (in which 
case user space probably enabled the symlink.)

	-hpa