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A comment on Meltdown and Spectre. Parent comment

Re:Meltdown and Spectre by zitterbewegung on Thursday January 04, 2018 @11:08AM (#16071408)
Bare metal servers that run trusted code like a build not are not effected. Maybe this will be a bios setting or a kernel flag to set .
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Re:Meltdown and Spectre by swsieber on Thursday January 04, 2018 @11:13AM (#16071443)
Kernel flag at compile time? - Yes

Kernel flag at boot time? - No (the fix is a to compile instructions differently).

Bare metal servers that only run trusted code are only unaffected so long as they explicitly opt out of the new security model, and I'm not sure how easy that'll be...

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Re:Meltdown and Spectre by FreedomWarrior on Thursday January 04, 2018 @11:40AM (#16071682)
IIUC it's not possible to opt out at this time (short of reverting the patches). Linus expressed some concern about it: https://lkml.org/lkml/2018/1/3/797
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Re:Meltdown and Spectre by slowmovintarget on Thursday January 04, 2018 @11:51AM (#16071802)
What a tl;dr!

  Please talk to management. Because I really see exactly two possibibilities:
 
  - Intel never intends to fix anything

  OR

  - these workarounds should have a way to disable them.

  Which of the two is it?
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Re:Meltdown and Spectre by walkingolof on Thursday January 04, 2018 @11:59AM (#16071869)
In case of Meltdown and Linux you simply set the boot parameter pti=off and reboot the machine.
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Re:Meltdown and Spectre by swsieber on Thursday January 04, 2018 @01:19PM (#16072626)
Ah, sorry. My comment was specifically directed at Spectre (though I didn't say it), the more serious of the two.
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Re:Meltdown and Spectre by blattimwind on Thursday January 04, 2018 @11:56AM (#16071843)
I feel like user-facing server-side scripting languages should be investigated whether they incur the same risk as running JavaScript in a browser (which is big and complicated). I'm thinking about stuff like Sievescript and IFTTT-like applications.
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