Re: [RESEND v3 PATCH 3/3] vfs: make mounts and mountstats honor root dir like mountinfo does

From: Dmitry V. Levin
Date: Mon Sep 29 2014 - 18:56:54 EST


On Mon, Sep 29, 2014 at 10:20:57PM +0100, Al Viro wrote:
> On Tue, Sep 30, 2014 at 12:26:59AM +0400, Dmitry V. Levin wrote:
>
> > > Again, we do not break userland.
> >
> > Occasionally, we do. If you say there was no chroot prefix removal in the
> > kernel before, and there seems to be a prefix removal for at least 5 years,
> > then there must have been a break some years ago that went unnoticed.
>
> D'oh! Yes, we did. And yes, it was quite a few years ago, actually - back
> in 2000. I plead being low on sleep and lower on caffeine...
>
> For a moment I was even afraid that it was my own doing, but no - it came
> in https://lkml.org/lkml/2000/1/16/54. Werner Almesberger. IIRC, I hadn't
> realized that it was going to cause fun problems back then - basically,
> by that point 2.3 and 2.2 had already diverged a lot and quite a few things
> got written off as "oh, well - upgrade from 2.2 to 2.4 is going to be not
> far from building the system from scratch anyway, and nobody sane would be
> using 2.3 on anything other than scratch filesystem - IDE broken more often
> than not, memory corruption aplenty, etc."

Thanks, I won't be able to locate the change that fast.

It also means that the phrase "show mountpoints relative to the root
directory" I used in the commit message is irrelevant and should be
removed to avoid confusion.

> My apologies. Hmm... Filtering the out-of-root ones out is probably OK,
> but let's put that into -next after 3.18-rc1 and see if anyone yells.

BTW, the cleanup patch (vfs: cleanup show_mountinfo) could be safely
applied anytime - it's completely harmless.


--
ldv
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/