On Mon, Apr 02, 2012 at 04:04:23PM -0400, David Quigley wrote:
On 04/02/2012 15:58, Richard W.M. Jones wrote:
>On Mon, Apr 02, 2012 at 08:32:56PM +0200, Miloslav Trmač wrote:
>>* #834 F18 Feature: /tmp on tmpfs -
>>
http://fedoraproject.org/wiki/Features/tmp-on-tmpfs (mitr,
>>17:40:06)
>> * AGREED: tmp-on-tmpfs is accepted (+5 -3) (mitr, 18:12:52)
>
>Actually I think this is a good feature, but ...
>
>The feature page is wrong about "The user experience should barely
>change. This is mostly a low-level change that has little visibility
>to the user."
>
>tmpfs is different in a number of important ways:
>
> - it's very limited in space compared to a real disk
>
> - it doesn't support O_DIRECT
>
> - it doesn't support user extended attrs; and not very old kernels
> didn't support any xattrs at all, meaning things like SELinux
> labels don't work
>
>All this means it's going to need a bit more testing, since
>potentially any package that stores a file on /tmp should be tested
>and may need to be fixed.
>
>Rich.
>
>--
>Richard Jones, Virtualization Group, Red Hat
>http://people.redhat.com/~rjones
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I really need to remember to send with the right user identity for
this list.
<resend of my message since its going to bounce>
That third part is not correct. tmpfs supports SELinux labels. If
you mount a tmpfs filesystem you'll see it reports seclabel as one
of the mount options. You can also just use chcon -t to set the type
on any file you like. SELinux labels are stored in the security
namespace which is separate from user extended attributes.
That's not what I said. I said that relatively recent kernels (up to
the middle of last year) didn't support system.*, and tmpfs doesn't
support user.* at all AFAICT.
Rich.
--
Richard Jones, Virtualization Group, Red Hat
http://people.redhat.com/~rjones
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