Description: x86/fpu: Don't cache access to fpu_fpregs_owner_ctx
References:
 https://bugzilla.kernel.org/show_bug.cgi?id=205663
 https://github.com/golang/go/issues/35777#issuecomment-561935388
Notes:
 carnil> Introduced in 5f409e20b7945 ("x86/fpu: Defer FPU state load
 carnil> until return to userspace") which is 5.2-rc1.
Bugs:
upstream: released (5.5-rc1) [59c4bd853abcea95eccc167a7d7fd5f1a5f47b98]
4.19-upstream-stable: N/A "Vulnerable code introduced later"
4.9-upstream-stable: N/A "Vulnerable code introduced later"
3.16-upstream-stable: N/A "Vulnerable code introduced later"
sid: released (5.3.15-1)
4.19-buster-security: N/A "Vulnerable code introduced later"
4.9-stretch-security: N/A "Vulnerable code introduced later"
3.16-jessie-security: N/A "Vulnerable code introduced later"