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  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:	Thu, 28 Jun 2007 10:53:08 +1000
From:	Nathan Scott <nscott@...nex.com>
To:	David Chinner <dgc@....com>
Cc:	Andreas Dilger <adilger@...sterfs.com>, xfs-oss <xfs@....sgi.com>,
	"Amit K. Arora" <aarora@...ux.vnet.ibm.com>,
	linux-fsdevel@...r.kernel.org, linux-ext4@...r.kernel.org,
	suparna@...ibm.com, cmm@...ibm.com
Subject: Re: [PATCH 4/7][TAKE5] support new modes in fallocate

On Thu, 2007-06-28 at 10:39 +1000, David Chinner wrote:
> 
> 
> I don't think it does - swapfile I/O looks like it goes direct to
> bio without passing through the filesystem.  When the swapfile is
> mapped, it scans and records the extent map of the entire swapfile
> in a separate structure and AFAICT the swap code uses that built map
> without touching the filesystem at all.
> 
> If that is true then the written/unwritten state of the extents is
> irrelevant; all we need is allocated disk space for the file and
> swapping should work. And it's not like anyone should be reading
> the contents of that swapfile through the filesystem, either. ;)

Ah, yes, good point - thats true.  Unwritten extents are ideal for
this then, as attempts to read swap via the regular interfaces will
return zeros instead of random swapped out memory contents.

cheers.

-
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists