diff options
| author | Borislav Petkov <[email protected]> | 2019-08-25 22:50:18 +0200 |
|---|---|---|
| committer | Borislav Petkov <[email protected]> | 2019-10-01 19:55:32 +0200 |
| commit | 7879fc4bdc7506d37bd67b6fc29442c53c06dfda (patch) | |
| tree | 6877dbd8fcb96773c98ead06bd2b1bdc51b5c388 /scripts/gcc-plugins/cyc_complexity_plugin.c | |
| parent | 54ecb8f7028c5eb3d740bb82b0f1d90f2df63c5c (diff) | |
x86/rdrand: Sanity-check RDRAND output
It turned out recently that on certain AMD F15h and F16h machines, due
to the BIOS dropping the ball after resume, yet again, RDRAND would not
function anymore:
c49a0a80137c ("x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h")
Add a silly test to the CPU bringup path, to sanity-check the random
data RDRAND returns and scream as loudly as possible if that returned
random data doesn't change.
Suggested-by: Linus Torvalds <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Cc: Pu Wen <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tom Lendacky <[email protected]>
Cc: x86-ml <[email protected]>
Link: https://lkml.kernel.org/r/CAHk-=wjWPDauemCmLTKbdMYFB0UveMszZpcrwoUkJRRWKrqaTw@mail.gmail.com
Diffstat (limited to 'scripts/gcc-plugins/cyc_complexity_plugin.c')
0 files changed, 0 insertions, 0 deletions