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Bug #12923

SMT exclusion should not balk at GZ

Added by Patrick Mooney about 1 month ago. Updated 28 days ago.

Status:
Closed
Priority:
Normal
Category:
kernel
Start date:
Due date:
% Done:

100%

Estimated time:
Difficulty:
Medium
Tags:
Gerrit CR:

Description

The SMT exclusion, used to mitigate some micro-architectural leakage between threads on a single core, currently ASSERT()-s that the caller is not running in the global zone. This prevents bhyve (which obeys the exclusion) from running in the GZ, at least in kernels build with DEBUG. This restriction is somewhat onerous for folks who want to run bhyve outside of a zone. (The easiest way to do so on vanilla illumos-gate right now)


Related issues

Related to illumos gate - Bug #12945: SMT exclusion should be by pid rather than zoneidNew

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History

#1

Updated by Patrick Mooney about 1 month ago

With the proposed patch, I was able to start a bhyve instance in the global zone on a DEBUG platform without an immediate ASSERT panic. The VM came up fine and was functional.

#2

Updated by Electric Monk about 1 month ago

  • Gerrit CR set to 770
#3

Updated by Patrick Mooney about 1 month ago

Mike Zeller confirmed that a mix of bhyve instances (both in the GZ and in NGZs) ran fine on a DEBUG kernel featuring this change.

#4

Updated by Patrick Mooney 28 days ago

  • Related to Bug #12945: SMT exclusion should be by pid rather than zoneid added
#5

Updated by Electric Monk 28 days ago

  • Status changed from New to Closed
  • % Done changed from 0 to 100

git commit fe354f7669cae68869feea028566f75f357ae5e7

commit  fe354f7669cae68869feea028566f75f357ae5e7
Author: Patrick Mooney <pmooney@pfmooney.com>
Date:   2020-07-10T18:06:27.000Z

    12923 SMT exclusion should not balk at GZ
    Reviewed by: Andy Fiddaman <andy@omniosce.org>
    Reviewed by: Mike Zeller <mike.zeller@joyent.com>
    Approved by: Joshua M. Clulow <josh@sysmgr.org>

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