Re: git: 84369dd52369 - main - x86: Probe the TSC frequency earlier

From: Shawn Webb <shawn.webb_at_hardenedbsd.org>
Date: Fri, 04 Mar 2022 14:24:47 UTC 
On Tue, Mar 01, 2022 at 02:39:55PM +0000, Mark Johnston wrote:
> The branch main has been updated by markj:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=84369dd52369cbae28970dca20a53d3de1719907
> 
> commit 84369dd52369cbae28970dca20a53d3de1719907
> Author:     Mark Johnston <markj@FreeBSD.org>
> AuthorDate: 2022-03-01 14:39:35 +0000
> Commit:     Mark Johnston <markj@FreeBSD.org>
> CommitDate: 2022-03-01 14:39:35 +0000
> 
>     x86: Probe the TSC frequency earlier
>     
>     This lets us use the TSC to implement early DELAY, limiting the use of
>     the sometimes-unreliable 8254 PIT.
>     
>     PR:             262155
>     Reviewed by:    emaste
>     Tested by:      emaste, mike tancsa <mike@sentex.net>, Stefan Hegnauer <stefan.hegnauer@gmx.ch>
>     MFC after:      1 month
>     Sponsored by:   The FreeBSD Foundation
>     Differential Revision:  https://reviews.freebsd.org/D34367
> ---
>  sys/amd64/amd64/machdep.c |  14 +++++-
>  sys/i386/i386/machdep.c   |  11 ++++-
>  sys/x86/include/clock.h   |   3 +-
>  sys/x86/isa/clock.c       |   4 +-
>  sys/x86/x86/tsc.c         | 123 +++++++++++++++++++++++++---------------------
>  5 files changed, 94 insertions(+), 61 deletions(-)

Hey Mark,

Something about this commit breaks booting in Hyper-V. Reverting this
particular commit makes Hyper-V happy again.

Thanks,

-- 
Shawn Webb
Cofounder / Security Engineer
HardenedBSD

https://git.hardenedbsd.org/hardenedbsd/pubkeys/-/raw/master/Shawn_Webb/03A4CBEBB82EA5A67D9F3853FF2E67A277F8E1FA.pub.asc