svn commit: r332994 - head/sys/amd64/amd64

[Tycho Nightingale]

> On Apr 25, 2018, at 10:30 AM, Oliver Pinter <oliver.pinter at hardenedbsd.org> wrote:
> 
> On Wednesday, April 25, 2018, Tycho Nightingale <tychon at freebsd.org <mailto:tychon at freebsd.org>> wrote:
> Author: tychon
> Date: Wed Apr 25 14:21:13 2018
> New Revision: 332994
> URL: https://svnweb.freebsd.org/changeset/base/332994 <https://svnweb.freebsd.org/changeset/base/332994>
> 
> Log:
>   If a trap is encountered upon executing iretq from within doreti() the
>   hardware will ensure the stack pointer is aligned to a 16-byte
>   boundary before saving the fault state on the stack.
> 
>   In the PTI case, handle this potential alignment adjustment by copying
>   both frames independently while unwinding the stack in between.
> 
>   Reviewed by:  kib
>   Sponsored by: Dell EMC Isilon
>   Differential Revision:        https://reviews.freebsd.org/D15183 <https://reviews.freebsd.org/D15183>
> 
> Is there any plan to MFC this commit? 

Yes, it seems reasonable to do that after 2 weeks.

Tycho