Re: [RESEND] Spectre-v2 (IBPB/IBRS) and SSBD fixes for 4.4.y

["Srivatsa S. Bhat" <srivatsa@csail.mit.edu>]

On 7/15/18 4:26 AM, Greg KH wrote:
> On Sat, Jul 14, 2018 at 02:25:43AM -0700, Srivatsa S. Bhat wrote:
>> Hi Greg,
>>
>> This patch series is a backport of the Spectre-v2 fixes (IBPB/IBRS)
>> and patches for the Speculative Store Bypass vulnerability to 4.4.y
>> (they apply cleanly on top of 4.4.140).
>>
>> I used 4.9.y as my reference when backporting to 4.4.y (as I thought
>> that would minimize the amount of fixing up necessary). Unfortunately
>> I had to skip the KVM fixes for these vulnerabilities, as the KVM
>> codebase is drastically different in 4.4 as compared to 4.9. (I tried
>> my best to backport them initially, but wasn't confident that they
>> were correct, so I decided to drop them from this series).
>>
>> You'll notice that the initial few patches in this series include
>> cleanups etc., that are non-critical to IBPB/IBRS/SSBD. Most of these
>> patches are aimed at getting the cpufeature.h vs cpufeatures.h split
>> into 4.4, since a lot of the subsequent patches update these headers.
>> On my first attempt to backport these patches to 4.4.y, I had actually
>> tried to do all the updates on the cpufeature.h file itself, but it
>> started getting very cumbersome, so I resorted to backporting the
>> cpufeature.h vs cpufeatures.h split and their dependencies as well. I
>> think apart from these initial patches, the rest of the patchset
>> doesn't have all that much noise. 
> 
> I've applied the "initial" patches to the 4.4-stable queue right now, as
> those were all just "housekeeping" stuff.  I'll let others review the
> rest of the series this week and see if anyone objects before throwing
> them at the test-bots.
> 

Sounds great! Thanks a lot!

> Many thanks for doing all of this work.
> 

Thank you Greg!
 
Regards,
Srivatsa
VMware Photon OS