On Tue, Nov 17, 2020 at 08:02:51PM +0100, Alexandre Chartre wrote: > No. This prevents the guest VM from gathering data from the host > kernel on the same cpu-thread. But there's no mitigation for a guest > VM running on a cpu-thread attacking another cpu-thread (which can be > running another guest VM or the host kernel) from the same cpu-core. > You cannot use flush/clear barriers because the two cpu-threads are > running in parallel.
Now there's your justification for why you're doing this. It took a while... The "why" should always be part of the 0th message to provide reviewers/maintainers with answers to the question, what this pile of patches is all about. Please always add this rationale to your patchset in the future. Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette