
Ksplice wins $100,000 in MIT start-up contest - peter123
http://news.cnet.com/8301-11386_3-10240865-76.html?part=rss&subj=news&tag=2547-1_3-0-20
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lincolnq
If you're into systems programming, read the paper!
<http://www.ksplice.com/paper>

The process they follow to apply a patch is:

\- compile the kernel without the patch, but using certain options
(-ffunction-sections and -fdata-sections, to produce location-independent
code). This is known as the _pre_ code.

\- compile the kernel with the patch and same options, producing the _post_
code.

\- perform a binary diff between _pre_ and _post_ to figure out what changed;
extract the changed functions and package them up into their own module.

\- perform a binary diff between the running kernel, known as _run_ , and the
_pre_ code. This is the _run-pre_ matching stage, and it has two goals: to
verify the assumption that they are fundamentally the same, and to get the
symbol addresses out of the running kernel. (Since _pre_ was compiled with
slightly different options, _run_ and _pre_ don't match up perfectly; the
paper explains how they can safely differ.)

\- use the symbol addresses learned during _run-pre_ matching to patch the
_post_ code

\- stop the machine at a safe point (no functions which are being updated can
be on any thread's call stack)

\- load the _post_ code into the running kernel as a new module, inserting
jump instructions at the beginnings of obsolete functions being replaced.

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dryicerx
KSplice seems to be a interesting concept, but seems like the product/service
is quite an unfit for the domain they are operating in (Linux Kernel updates).

The KSplice software is open source under GNU, so why not a community behind
KSplice's technology simply package these (just like you would deb or rpm
packages) and publish them freely (instead of having to pay KSplice, Inc
simply to convert these diff's in to KSplice format).

The technology is wonderful, and I am very glad they open sourced it as well,
but I am just wondering why they made it a Inc (assuming it's for-profit with
their subscription service) instead of making it a open source project.

Source: <http://en.wikipedia.org/wiki/Ksplice> Source:
<http://www.youtube.com/watch?v=dhbRyLATEPo>

~~~
ShabbyDoo
The only obvious exit strategy is an "HR acquisition".

------
3ds
At first I thought it was all about Windows and I'm like "on linux there's no
rebooting necessary!" mumbling: "except for kernel updates"

But reading the website, it turns out, that they seem to have found a way to
do kernel updates without rebooting. Big Up!

And it seems like they want to support all major and minor OS.

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sadiq
The write-up didn't fill me with confidence but their website actually has a
more technical take on things.

It seems to be (atleast initially) a way of updating the Linux kernel without
rebooting.

<http://www.ksplice.com/>

