GEOM_ULZMA

[Alexandr Rybalko]

On Wed, 3 Mar 2010 07:35:55 +0100
Pawel Jakub Dawidek <pjd at FreeBSD.org> wrote:

>> On Tue, Mar 02, 2010 at 08:32:20PM +0100, Dimitry Andric wrote:
>> > On 2010-03-02 09:47, Alexandr Rybalko wrote:
>> > >>>Definiatelly separately, not sure where. There is ongoing discussion
>> > >>>somwhere on importing this algorithm to the base for tar(1) to use, it
>> > >>>would be best to have only one copy of code in the tree.
>> > >I have already said, that it would be good for embedded platforms have 
>> > >only one copy of the code for the kernel and userland.
>> > >It is not thought of how done it.
>> > 
>> > I think Pawel means the *source* code in this case, not the executable
>> > code.  E.g. lzma source should most likely go under /usr/src/contrib,
>> > and be built separately for kernel and userland.
>> 
>> If it is going to be used be the kernel it has to be under sys/.
>> 
>> And yes, I was talking about one copy of the source, not executable.
>> I think it would be bad idea to do compression in the kernel for
>> userland applications for many reasons - the most important one is
>> security. Look at projects like Capsicum where Robert closed for example
>> gzip in a tight sandbox and gzip is not even set-uid and giving it
>> chance to gain kernel access when bug is found is very, very bad.
>> Another reason is performance. You can see how much faster, eg. openssl
>> crypto is when doing it in userland and when forcing it to use software
>> crypto from the opencrypto kernel framework.

Ok, already forgotten. 
Well, LZMA code is not so big, so will use two copies for kernel and for userland.

It is possible to have number of different version of LZMA in kernel source tree?

>> 
>> -- 
>> Pawel Jakub Dawidek                       http://www.wheelsystems.com
>> pjd at FreeBSD.org                           http://www.FreeBSD.org
>> FreeBSD committer                         Am I Evil? Yes, I Am!


-- 
Alexandr Rybalko <ray at dlink.ua> 
aka Alex RAY <ray at ddteam.net>