Re: [patch 09/14] tmpfs: disallow CONFIG_TMPFS_INODE64 on alpha

[Arnd Bergmann <arnd@kernel.org>]

On Wed, Feb 10, 2021 at 8:17 PM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> On Wed, Feb 10, 2021 at 5:39 AM Heiko Carstens <hca@linux.ibm.com> wrote:
> >
> > I couldn't spot any and also gave the patch below a try and my system
> > still boots without any errors.
> > So, as far as I can tell it _should_ be ok to change this.
>
> So your patch (with the fix on top) looks sane to me.
>
> I'm not entirely sure it is worth it, but the fact that we've had bugs
> wrt this before does seem to imply that we should do this.
>
> I'd remove the __kernel_ino_t type entirely, but I wonder if user
> space might depend on it. I do find
>
>    #ifndef __kernel_ino_t
>    typedef __kernel_ulong_t __kernel_ino_t;
>    #endif
>
> in the GNU libc headers I have, but then I don't find any actual use
> of that, so it looks like it may be jyst a "we copied things for other
> reasons".

I checked debian codesearch to see if there are any users in
distro source code and found exactly one instance that will
definitely break at compile time:

https://sources.debian.org/src/nfs-utils/1:1.3.4-4/support/include/nfs/nfs.h/?hl=99#L99

This is a copy of a kernel header that was removed ten years ago
with commit c152292f9ee7 ("nfsd: remove include/linux/nfsd/syscall.h").

The mainline version of that package removed the contents in 2016 in
the following release (2.1.1), but debian is still on the previous
version (1.3.4)
http://git.linux-nfs.org/?p=steved/nfs-utils.git;a=commitdiff;h=fc1127d754578cd1

Someone will have to update the package for Debian, but it seems
that would be a good idea anyway.

      Arnd