linux-kernel - Re: [RFC/PATCH] - revert generic_fillattr stat->blksize to PAGE_CACHE

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:	Mon, 06 Nov 2006 19:39:10 -0600
From:	Eric Sandeen <sandeen@...hat.com>
To:	Eric Sandeen <sandeen@...hat.com>,
	Christoph Hellwig <hch@...radead.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>,
	Theodore Tso <tytso@....edu>
Subject: Re: [RFC/PATCH] - revert generic_fillattr stat->blksize to PAGE_CACHE_SIZE

Andreas Dilger wrote:
> On Nov 06, 2006  17:15 -0600, Eric Sandeen wrote:
>> Christoph Hellwig wrote:
>>> I agree with the conclusion, but the patch is incomplete.  You went down
>>> all the way to find out what the fileystems do in this messages, so add
>>> the hunks to override the defaults for non-standard filesystems to the
>>> patch aswell to restore the pre-inode diet state.
>> Well, agreed.  I put 80% or more back to pre-patch state, but not all.
>> :)  So it's less broken with my patch than without, so at least it's
>> moving forward.  So... Ted's patches get in w/o fixing up all the other
>> filesystems (left as an exercise to the patch reader) but mine can't? :)
> 
> Actually, rather than blindly revert to pre-patch behaviour it would be
> worthwhile to determine if PAGE_SIZE isn't the better value.  In some
> cases people don't understand that i_blksize is the "optimal IO size"
> and instead assume it is the filesystem blocksize.  I saw a few that were
> e.g. 512 and that can't be very useful.

I'm willing to either revert everyting to pre-inode-diet behavior, or leave it 
at the (newly re-proposed) page size default and let the other fs maintainers 
sort it out for their own codebase, but I don't pretend to know what is best 
for, say, qnx4 etc...  I'd be willing to cc: all maintainers asking them to take 
another long hard look at their code. :)

As we saw with cifs, these changes can have unintended consequences (not picking 
on cifs, it's just one that ran into issues with the broad-stroke change).

-Eric
-
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/