Re: [PATCH] fs: Remove duplicated flag from VALID_OPEN_FLAGS

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

On Fri, May 22, 2020 at 10:01:19AM -0700, Matthew Wilcox wrote:
> On Fri, May 22, 2020 at 04:47:19PM +0100, Al Viro wrote:
> > On Fri, May 22, 2020 at 01:37:23PM +0000, Krzysztof Wilczynski wrote:
> > > From: Krzysztof Wilczyński <kw@linux.com>
> > > 
> > > Also, remove extra tab after the FASYNC flag, and keep line under 80
> > > characters.  This also resolves the following Coccinelle warning:
> > > 
> > >   include/linux/fcntl.h:11:13-21: duplicated argument to & or |
> > 
> > Now ask yourself what might be the reason for that "duplicated argument".  
> > Try to figure out what the values of those constants might depend upon.
> > For extra points, try to guess what has caused the divergences.
> > 
> > Please, post the result of your investigation in followup to this.
> 
> I think the patch is actually right, despite the shockingly bad changelog.
> He's removed the duplicate 'O_NDELAY' and reformatted the lines.

So he has; my apologies - the obvious false duplicate in there would be
O_NDELAY vs. O_NONBLOCK and I'd misread the patch.

Commit message should've been along the lines of "O_NDELAY occurs twice
in definition of VALID_OPEN_FLAGS; get rid of the duplicate", possibly
along with "Note: O_NONBLOCK in the same expression is *not* another
duplicate - on sparc O_NONBLOCK != O_NDELAY (done that way for ABI
compatibility with Solaris back when sparc port began)".