Re: Linux 4.15-rc7

From: Thomas Gleixner
Date: Mon Jan 08 2018 - 02:20:55 EST


Linus,

On Sun, 7 Jan 2018, Linus Torvalds wrote:

> The one thing I want to do now that Meltdown and Spectre are public,
> is to give a *big* shout-out to the x86 people, and Thomas Gleixner in
> particular for really being on top of this. It's been one huge
> annoyance, and honestly, Thomas really went over and beyond in this
> whole mess. A lot of other people have obviously been involved too,
> don't get me wrong, but this is exactly the kind of issue that easily
> results in lots of nasty hacky patches because people are falling all
> over themselves trying to fix it and they can't even talk about why
> they are doing it in public, and Thomas &co ended up being a huge
> reason for why it was all much easier for me to merge: because of the
> literally _months_ of work on quality control and gating these patches
> and making sure the end result was a clean and manageable series.
>
> So a big *BIG* thanks to Thomas for making it so much easier for me to
> merge all this stuff. The whole nasty TLB isolation patches would
> have been just _so_ much more horrible without him.

I'm deeply moved and feel a little ashamed as without the help of others
this wouldn't have been possible at all. So it's on me to hand over the
*BIG* thanks to:

Ingo Molnar who was the git logistics mastermind behind this, the last
sanity check before commit and the initial stress tester. Thanks
especially for taking over most of the regular tip maintenance workload.

Andi Lutomirksy for the great work on the entry code, cpu entry area, LDT
mapping and the PCID rework and his reviews.

Borislav Petkov for his meticulous reviews, his help with all AMD issues
and being always on standby for testing and debugging despite his
workload of backporting KAISER to dead kernels.

Peter Zijlstra for his work on the tlb flush / PCID code, reviews and
supporting me on the short trip into LDT VMA mapping which we had to drop
for various reasons.

Dave Hansen who did the initial KAISER port and helped all along with the
rework in various ways

Josh Poimboeuf for fixing up all the stacktrace issues we encountered

Juergen Gross for helping out on the XEN side of things so we did
not have to dig into the inwards of XEN/PV.

Kess Cook for helping with coordination behind the scenes

Greg Kroah-Hartman for not pestering us with all the pre 4.14 backports
and the smooth integration and exposure to 4.14 stable which gave us more
test coverage and helped us to iron out the inevitable hickups.

Linus for keeping his diving harpune in the cabinet and giving us great
support for getting this into his tree on time which allowed 4.14 to gain
all the goods as well.

The team at TU Graz who did the initial KAISER implementation. I'm really
impressed what kernel first timers can achieve and I have to say that I
see worse code in my daily work as a maintainer. Congrats to them for
their findings in the guts of our CPUs as well. Really impressive!

This list is surely not complete, so I extend the thanks to everyone who
helped with review, patches, testing, bug reports and regression hunting.

I want to take the opportunity to say thanks to my wife Monika, my family
and my great team @linutronix for bearing with the extraordinary grumpy old
greybeard which I certainly was for the past two month.

It's been an interesting challenge to sort that out in such a short
timeframe, but I'm sure all of the involved people would have preferred to
do this with the head start which at least one other OS got on this.

But it's not time yet for a post-mortem of this mess, we still have to sort
out the spectre mitigations and it seems Linus expects me to keep my hand
on things for the next time. Aye, aye, captain!

Lets sort this in a technical manner, with the security of our users in
mind and then take a break and after that sit down and gain the performance
back which we lost on the way. Lots of work ahead.

Thanks,

Thomas