1707955 - Disable Spectre Mitigations for Desktop

Status: NEW

(Core :: JavaScript Engine: JIT, enhancement, P3)

Description

[Tom Ritter [:tjr] (OOTO Oct 18-26)]

This bug tracks disabling JIT Mitigations for Spectre. Its dependencies will cover all of the "Data in a Content Process we may not want to leak", but the priority of each will determined in the future.

This is blocked by Fission as well as the individual bugs but because Fission-Android is more nebulous we will only be disabling the mitigations on desktop for now.

Comment 1

[Nicolas B. Pierron [:nbp]]

(In reply to Tom Ritter [:tjr] (ni? for response to sec-[advisories/bounties/ratings/cves]) from comment #0)

This is blocked by Fission […]

I presume we might also want to have a grace period where the instrumentation is simply disabled and not removed.

Also, SpiderMonkey is embedded in other applications which might not have any Fission equivalent.

Comment 2

[Tom Ritter [:tjr] (OOTO Oct 18-26)]

(In reply to Nicolas B. Pierron [:nbp] from comment #1)

(In reply to Tom Ritter [:tjr] (ni? for response to sec-[advisories/bounties/ratings/cves]) from comment #0)

This is blocked by Fission […]

I presume we might also want to have a grace period where the instrumentation is simply disabled and not removed.

Also, SpiderMonkey is embedded in other applications which might not have any Fission equivalent.

Yes; and internally because of Android actually removing the mitigations will be a future milestone.

Comment 3

[Olli Pettay [:smaug][[e-mail]]]

Trying to make dependency tree a bit more manageable for speedometer3.
Fission has shipped, so this doesn't really depend on that anymore, but things like ORB.

Comment 4

[Olli Pettay [:smaug][[e-mail]]]

Bug 1851162 landed, so this doesn't need to block sp3.