Speculative execution side channel attacks can read the
entire FPU/SIMD register state on affected Intel Core
processors, see CVE-2018-3665.
We now have two options for managing floating point
context between threads on x86: CONFIG_EAGER_FP_SHARING
and CONFIG_LAZY_FP_SHARING.
The mitigation is to unconditionally save/restore these
registers on context switch, instead of the lazy sharing
algorithm used by CONFIG_LAZY_FP_SHARING.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
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