

What's new in Linux 3.2 - codepopacy
http://h-online.com/-1400680

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jsvaughan
The algorithm for determining when writeback from memory to persistent storage
is interesting:

<https://lwn.net/Articles/456904/>

(Linked from <http://kernelnewbies.org/Linux_3.2>, which has more detail than
the HN posted article)

~~~
sciurus
I'm curious what is viewed as a backing device. Lets say I have a SAN
exporting three volumes via iSCSI to a single server. Does this patch think
those volumes share a single BDI, or does it treat them separately?

~~~
obtu
I think the three volumes will be seen as independent BDIs, because that's the
simplest implementation (look at the block device the pages are for, don't
attempt to count things at multiple levels). Being too granular isn't a
problem, because a process will be slowed down if it writes to any of the
three iSCSI volumes that are throttled by the network.

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keeperofdakeys
Making the RC6 engine for Intel graphics the default was reverted at the last
minute due to instability,
[http://www.phoronix.com/scan.php?page=news_item&px=MTAzN...](http://www.phoronix.com/scan.php?page=news_item&px=MTAzNDg).
It can still be enabled manually by adding i915.i916_enable_rc6=1 to the
kernel boot parameters, just like 3.1.

Another interesting change concerning Logitech Unifying devices is that
multiple devices are now given separate /dev entries, instead of being
multiplexed into one device.

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nodata
The EVM part interests me. It provides a way of guaranteeing that a file has
not been changed by using a combination of a passphrase and a key stored in
the TPM, along with hashes of files stored as xattrs on disk.

More info here: <http://lwn.net/Articles/394170/>

One question I have though is how to guarantee that the kernel hasn't been
modified to misread the xattrs or log the passphrase. Anyone know?

~~~
sp332
TCCBOOT? You could verify the source code of the kernel on a thumb drive, then
boot the computer with TCCBOOT and compile the kernel from source every time
you boot the computer. <http://bellard.org/tcc/tccboot.html>

~~~
astro1138
Does your compiler compile itself twice before? 100% security is just never
achievable.

~~~
sp332
Ah yes, the old Reflections on Trusting Trust. <http://cm.bell-
labs.com/who/ken/trust.html> Fortunately that wasn't nodata's question.
Recompiling the kernel from known source should ensure that it hasn't been
modified to misread xattrs.

~~~
mc32
I found his moral section on security interesting: "...The acts performed by
these kids are vandalism at best and probably trespass and theft at worst. It
is only the inadequacy of the criminal code that saves the hackers from very
serious prosecution."

and

"I have watched kids testifying before Congress. It is clear that they are
completely unaware of the seriousness of their acts. There is obviously a
cultural gap. The act of breaking into a computer system has to have the same
social stigma as breaking into a neighbor's house."

So while interested in trusted code and security, he was also interested in
criminal penalties for unauthorized access to computer systems. Of course,
it's an unstoppable force and the metaphor with the real world is tenuous
--it's just an interesting take.

~~~
sp332
There is absolutely nothing stopping most people from just breaking a window
and climbing into their neighbor's houses. But people don't generally do that,
because there's a social stigma against it. There's no security around men's
and women's bathrooms to make sure only the "right" people go in, but people
know they shouldn't do that. There's no physical barrier on (most) roads to
prevent a driver from going on the other side of the road, or ignoring lights,
but drivers take courses that explain how to drive properly. That's the kind
of cultural gap he's talking about. Stealing is easy, but we teach kids from
an early age to respect each other's property. We could easily instill the
same respect for digital territory, but culture hasn't caught up yet. I think
it will soon though.

~~~
mc32
The digital realm does introduce remoteness[1] too though -and there isn't the
possibility of immediate repercussions (as one can find in the physical
world).

Additionally, the number of people who trespass digital properties are very
few, relatively speaking and could be compared to scofflaws, drunk drivers,
etc. but, and this is the big but, their impact is asymmetrical. They can have
an effect on large numbers of people.

Despite that, I do agree that culture can be changed in a generation.

[1] It's impersonal and removed.

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Roboprog
So does that mean there will soon be distro support for the newer netbooks?
(full sizish keyboards under an 11 inch monitor with slightly faster AMD CPU
is the payoff, but the graphics and wifi have been problematic from what I
understand)

It's an important tangent to me: I like the very small laptop form, but the
newer models have not been well supported yet.

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dguido
Do they still ship with an out-of-date version of AppArmor? I'm pretty sure
the vanilla linux kernel is stuck at version 2.3.1.

It looks like Ubuntu ships with version 2.7 now:
<http://wiki.apparmor.net/index.php/AppArmor_versions>

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FranProgrammer
I always wanted to be a Linux Kernel Developer. At least, help them with the
most tedious task. Where can I start?

~~~
xtacy
<http://kernelnewbies.org> is an excellent resource to get you started. They
recommend starting here: <http://kernelnewbies.org/KernelJanitors>. I would
also recommend subscribing to the KernelNewbies mailing list, to participate
and ask questions.

Good luck!

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squarecat
Soooo, anyone care to translate this into Bourgeois Geek? o_O

