linux-kernel - Re: [RFC][PATCH] block: Isolate the buffer cache in it's own mappings.

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]

Message-Id: <200710211424.46650.nickpiggin@yahoo.com.au>
Date:	Sun, 21 Oct 2007 14:24:46 +1000
From:	Nick Piggin <nickpiggin@...oo.com.au>
To:	"Eric W. Biederman" <ebiederm@...ssion.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Chris Mason <chris.mason@...cle.com>,
	Christian Borntraeger <borntraeger@...ibm.com>,
	linux-mm@...ck.org, linux-kernel@...r.kernel.org,
	Martin Schwidefsky <schwidefsky@...ibm.com>,
	"Theodore Ts'o" <tytso@....edu>, stable@...nel.org
Subject: Re: [RFC][PATCH] block: Isolate the buffer cache in it's own mappings.

On Saturday 20 October 2007 07:27, Eric W. Biederman wrote:
> Andrew Morton <akpm@...ux-foundation.org> writes:
> > I don't think we little angels want to tread here.  There are so many
> > weirdo things out there which will break if we bust the coherence between
> > the fs and /dev/hda1.
>
> We broke coherence between the fs and /dev/hda1 when we introduced
> the page cache years ago,

Not for metadata. And I wouldn't expect many filesystem analysis
tools to care about data.

> and weird hacky cases like 
> unmap_underlying_metadata don't change that.

unmap_underlying_metadata isn't about raw block device access at
all, though (if you write to the filesystem via the blockdevice
when it isn't expecting it, it's going to blow up regardless).

> Currently only 
> metadata is more or less in sync with the contents of /dev/hda1.

It either is or it isn't, right? And it is, isn't it? (at least
for the common filesystems).
-
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/