Messages in this thread | | | Date | Thu, 15 Aug 2019 23:05:47 +0200 | From | Borislav Petkov <> | Subject | Re: [PATCH] x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h |
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On Thu, Aug 15, 2019 at 09:59:03PM +0100, Andrew Cooper wrote: > If you're virtualised, the write to MSR_AMD64_CPUID_FN_1 almost > certainly won't take effect, which means userspace will still be able to > see the bit.
msr_clear_bit() has a return value. We should check it before doing anything further. I hope the HV actually signals the write success/failure properly so that we get a correct return value.
-- Regards/Gruss, Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
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