gregkh

Citation needed :)

Seriously, all software has bugs, how do you judge the quality of an operating system that is not finished?

Yes, it is used, but of course it is not all-inclusive to handle all hardware types out there in the world. That takes actual real-world usage to exercise that, although kernelci is starting to pick up the slack in that area.

> Does a userspace filesystem loose a lot of performance...

Yes.

Try the two versions out, and see for yourself if you are curious.

It will be in the "real" kernel soon, here is a patch I submitted adding it: https://lore.kernel.org/lkml/20190828160817.6250-1-gregkh@li...

And yes, this is _much_ better than using a FUSE interface to the filesystem.

This is one of the first times that I know of that the Linux kernel and Windows kernel developers discussed a security issue together directly. So while the fix was much simpler than Meltdown/Spectre was (Linux was fixed with a patch that was written in 2015) overall, the communication between different OS kernel developers right now is very good.

And yes, it is all due to the horrible Meltdown/Spectre problem and how that was handled. We were not allowed to work together for that problem, and we do not want to that to happen again.

Yes, once the patches are generated, they get submitted just like any other kernel change, sent to the responsible subsystem and maintainer for inclusion like any other kernel change.

Linux has a security team/list that does handle disclosures and fixing of reported problems. It usually does this by just dragging in the responsible parties, but many times it just fixes the problems themselves and submits the patches to the proper part of the kernel.

For details on how this works, please see the kernel documentation itself: https://www.kernel.org/doc/html/latest/admin-guide/security-...

The kernel development model is documented here: http://lxr.free-electrons.com/source/Documentation/developme...

Github doesn't scale at all for large projects. The kernel is averaging over 8 changes an hour, 24 hours a day. That rate of change can never be handled by doing pull requests and web site review. It only can work with email and review and scriptable processes.

And take a look at those permissions on your machine and see what they show for you:

crw-rw-rw- 1 root root 1, 8 Jul 15 11:27 /dev/random

crw-rw-rw- 1 root root 1, 9 Jul 15 11:27 /dev/urandom

So, if the default permission is read/write by any user, what limitation should this new syscall add?

Try contacting the Linux kernel RCU maintainer, he should be able to look into if IBM is willing to do this or not.

Odds are, they are not, it was a very specific decision to let this be a GPLv2 only patent grant, but as I haven't worked for IBM for almost a decade, I can't speak for them in any form (not that I ever could...)

Good digging.

If the original RCU patents are expired, it might make more sense for the BSDs to start to use RCU, it makes things much easier in the long run, and should scale a lot better than this proposed solution.

Why wouldn't it be?

It's "out of tree" due to licensing issues (i.e. Oracle is not releasing it under a GPLv2 compatible license for various reasons...)

SuSE has been using btrfs as their "default stable production filesystem" for a few years now, with no problems.

So it isn't a "recent" change at all.