Re: [PATCH 1/9] binfmt_misc: let a register string create an entry disabled

On Mon, Aug 3, 2026 at 10:18 AM Christian Brauner <[email protected]> wrote:
>
> On Sun, Aug 02, 2026 at 04:37:58PM -0700, Farid Zakaria wrote:
> > On Thu, 30 Jul 2026 15:34:03 +0200, Christian Brauner <[email protected]> wrote:
> > > diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
> > > index 707f8a14f8a6..ca7840b01a2b 100644
> > > --- a/fs/binfmt_misc.c
> > > +++ b/fs/binfmt_misc.c
> > > @@ -75,6 +86,7 @@ static const struct binfmt_misc_flag misc_flags[] = {
> > >     { 'F', MISC_FMT_OPEN_FILE,      0,                      "open interpreter file now"     },
> > >     { 'T', MISC_FMT_TRANSPARENT,    MISC_FMT_OPEN_BINARY,   "transparent"                   },
> > >     { 'L', MISC_FMT_LOADER,         0,                      "loader substitution"           },
> > > +   { 'D', MISC_FMT_DISABLED,       0,                      "register disabled"             },
> >
> > AI brought up an interesting point that this now changes the set of
> > valid delimiters which you might want to call out in the commit message.
> >
> > For instance 'DnameDMD0DmagicDDinterpD' was allowed before.
> > It might be a very obscure feature to pick a delimiter because
> > https://docs.kernel.org/admin-guide/binfmt-misc.html does not even
> > mention it beyond 'where you can choose the : upon your needs'.
>
> Yeah, I can send a separate doc addition for that. But that's kinda true
> for any new thing we give meaning. So _shrug_.

I figured but thought it was worth calling out.
Maybe you will want to reserve A-Z for non-delimiters; the
documentation seems to point readers
to #:;- all sensible options. I don't have the history about this.

Having a growing flag set and arbitrary delimiters seems odd.

I am headed to DEFCON tomorrow but I saw a few more patch series will
go through.
They are getting a little more esoteric for me though :)