linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jamie Lokier <jamie@shareable.org>
To: James Bottomley <James.Bottomley@suse.de>
Cc: akpm@linux-foundation.org, viro@zeniv.linux.org.uk,
	linux-fsdevel@vger.kernel.org, fengguang.wu@intel.com,
	davem@davemloft.net, eparis@redhat.com, hch@infradead.org,
	rdreier@cisco.com, schwab@linux-m68k.org, sfr@canb.auug.org.au
Subject: Re: [patch 2/5] vfs: O_* bit numbers uniqueness check
Date: Fri, 27 Aug 2010 02:27:00 +0100	[thread overview]
Message-ID: <20100827012700.GK3574@shareable.org> (raw)
In-Reply-To: <1282864959.8133.67.camel@mulgrave.site>

James Bottomley wrote:
> On Tue, 2010-07-20 at 15:29 -0700, akpm@linux-foundation.org wrote:
> > From: Wu Fengguang <fengguang.wu@intel.com>
> > 
> > The O_* bit numbers are defined in 20+ arch/*, and can silently overlap. 
> > Add a compile time check to ensure the uniqueness as suggested by David
> > Miller.
> 
> Can we get this reverted or fixed?  It's causing the parisc compiles to
> fail.  The reason is O_NONBLOCK on parisc has a dual value:
> 
> #define O_NONBLOCK	000200004 /* HPUX has separate NDELAY & NONBLOCK */
> 
> The fix would be to take O_NONBLOCK out.

A more thoroughly checking fix would be

BUILD_BUG_ON(18 - 1 /* For O_RDONLY being 0 */
             + HWEIGHT32(O_NONBLOCK) /* Because it's 2 bits on parisc */
             != HWEIGHT32(    .... all the bits ....     ));

Am I allowed to Sign-off handwavy pseudocode? ;-)

-- Jamie

  reply	other threads:[~2010-08-27  1:27 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-07-20 22:29 [patch 2/5] vfs: O_* bit numbers uniqueness check akpm
2010-08-26 23:22 ` James Bottomley
2010-08-27  1:27   ` Jamie Lokier [this message]
2010-08-27  5:53     ` James Bottomley
2010-09-04  1:22       ` [PATCH] vfs: take O_NONBLOCK out of the O_* uniqueness test Wu Fengguang
  -- strict thread matches above, loose matches on Subject: below --
2010-05-24 19:24 [patch 2/5] vfs: O_* bit numbers uniqueness check akpm

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20100827012700.GK3574@shareable.org \
    --to=jamie@shareable.org \
    --cc=James.Bottomley@suse.de \
    --cc=akpm@linux-foundation.org \
    --cc=davem@davemloft.net \
    --cc=eparis@redhat.com \
    --cc=fengguang.wu@intel.com \
    --cc=hch@infradead.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=rdreier@cisco.com \
    --cc=schwab@linux-m68k.org \
    --cc=sfr@canb.auug.org.au \
    --cc=viro@zeniv.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).