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Date:   Tue, 3 Sep 2019 18:56:10 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Christoph Hellwig <hch@infradead.org>
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Subject: Re: "fs/namei.c: keep track of nd->root refcount status" causes boot
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On Tue, Sep 03, 2019 at 08:39:30AM -0700, Christoph Hellwig wrote:

> > There's much nastier situation than "new upstream kernel released,
> > need to rebuild" - it's bisect in mainline trying to locate something...
> 
> I really don't get the point.  And it's not like we've card about
> this anywhere else.  And jumping wildly around with the numeric values
> for constants will lead to bugs like the one you added and fixed again
> and again.

The thing is, there are several groups - it's not as if all additions
were guaranteed to be at the end.  So either we play with renumbering
again and again, or we are back to the square one...

Is there any common trick that would allow to verify the lack of duplicates
at the build time?

Or we can reorder the list by constant value, with no grouping visible
anywhere...