Linux Patch Posted For Cross-Hyperthread Spectre Mitigation With STIBP

[phoronix]

Phoronix: Linux Patch Posted For Cross-Hyperthread Spectre Mitigation With STIBP

The latest Linux kernel patch coming to light in the Spectre space is by SUSE's Jiri Kosina for enabling cross-hyperthreaded Spectre V2 STIBP mitigation...

http://www.phoronix.com/scan.php?page=news_item&px=Linux-Spectre-V2-STIBP-Patch

[dwagner]

Too bad that this patch cannot possibly help against L1TF, so Intel CPU owners will still need to disable hyperthreading if they want to be safe.

[tildearrow]

What STIBP provides on supported CPUs/microcodes is from indirect branch predictions from being controlled by the sibling hyper-thread.

I feel like there is a typo...

[tildearrow]

Too bad that this patch cannot possibly help against L1TF, so Intel CPU owners will still need to disable hyperthreading if they want to be safe.

Too bad that this patch cannot possibly help against the other thousand Intel vulnerabilities to be discovered, so Intel CPU owners will still need to disable their processors and buy AMD if they want to be safe.

[hiryu]

This doesn't sound specific to hyperthreading, but does sound specific to SMT (of which hyperthread qualifies). Does this mean AMD is vulnerable? Does it mean that other architectures with SMT are vulnerable? Ie, IBM POWER, Sun/Oracle Niagra chips, and so on?