Re: [PATCH v3 0/2] openat2: minor uapi cleanups

[Al Viro <viro@zeniv.linux.org.uk>]

On Sat, Jan 18, 2020 at 11:07:58PM +1100, Aleksa Sarai wrote:
> Patch changelog:
>   v3:
>    * Merge changes into the original patches to make Al's life easier.
>      [Al Viro]
>   v2:
>    * Add include <linux/types.h> to openat2.h. [Florian Weimer]
>    * Move OPEN_HOW_SIZE_* constants out of UAPI. [Florian Weimer]
>    * Switch from __aligned_u64 to __u64 since it isn't necessary.
>      [David Laight]
>   v1: <https://lore.kernel.org/lkml/20191219105533.12508-1-cyphar@cyphar.com/>
> 
> While openat2(2) is still not yet in Linus's tree, we can take this
> opportunity to iron out some small warts that weren't noticed earlier:
> 
>   * A fix was suggested by Florian Weimer, to separate the openat2
>     definitions so glibc can use the header directly. I've put the
>     maintainership under VFS but let me know if you'd prefer it belong
>     ot the fcntl folks.
> 
>   * Having heterogenous field sizes in an extensible struct results in
>     "padding hole" problems when adding new fields (in addition the
>     correct error to use for non-zero padding isn't entirely clear ).
>     The simplest solution is to just copy clone(3)'s model -- always use
>     u64s. It will waste a little more space in the struct, but it
>     removes a possible future headache.
> 
> This patch is intended to replace the corresponding patches in Al's
> #work.openat2 tree (and *will not* apply on Linus' tree).
> 
> @Al: I will send some additional patches later, but they will require
>      proper design review since they're ABI-related features (namely,
> 	 adding a way to check what features a syscall supports as I
> 	 outlined in my talk here[1]).

#work.openat2 updated, #for-next rebuilt and force-pushed.  There's
a massive update of #work.namei as well, also pushed out; not in
#for-next yet, will post the patch series for review later today.