lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Wed, 10 Aug 2011 06:26:04 -0400
From:	Christoph Hellwig <hch@...radead.org>
To:	Miklos Szeredi <miklos@...redi.hu>
Cc:	Christoph Hellwig <hch@...radead.org>,
	Johannes Weiner <jweiner@...hat.com>,
	fuse-devel@...ts.sourceforge.net, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: Re: [patch 1/2] fuse: delete dead .write_begin and .write_end aops

On Mon, Aug 08, 2011 at 05:05:20PM +0200, Miklos Szeredi wrote:
> > The loop code still calls them uncondtionally.  This actually is a big
> > as write_begin and write_end require filesystems specific locking,
> > and might require code in the filesystem to e.g. update the ctime
> > properly.  I'll let Miklos chime in if leaving them in was intentional,
> > and if it was a comment is probably justified.
> 
> Loop checks for ->write_begin() and falls back to ->write if the former
> isn't defined.
> 
> So I think the patch is fine.  I tested loop over fuse, and it still
> works after the patch.

It works, but it involves another data copy, which will slow down
various workloads that people at least historically cared about.

And yes, unconditionally above was wrong - calls them if present without
taking care of filesystem specific locking would be the right term.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ