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A comment on Reading privileged memory with a side-channel. Parent comment

Re:Reading privileged memory with a side-channel by tankenmate on Thursday January 04, 2018 @04:47AM (#16069080)
But if you use AMD ASID it blocks this as memory mappings for VM guests are in a completely separate address space.

What I was wondering was for local OS user mode to local OS root / kernel mode access; i.e. user to kernel privilege escalation.

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Re:Reading privileged memory with a side-channel by caf on Thursday January 04, 2018 @05:58AM (#16069361)
It isn't obvious at all how a separate address space would block that method.

What would block it is flushing the branch predictor state when switching privilege levels and/or address spaces.

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