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Dave proposed another option of using > a percpu boolean to track the need for flushing: > > https://lore.kernel.org/lkml/20250416230259.97989-1-kai.huang@intel.com/ > > One advantage of the percpu boolean is for TDX we could do optimization > to do: > > wbinvd(); > percpu(boolean) = 0; > > for all CPUs at early stage to avoid having to do WBINVD in > stop_this_cpu() at kexec time. I made a RFC patch to show the idea: > > https://github.com/intel/tdx/commit/d9f0123b1d63ba24f472da6971181939ce53d2e3 > > I'll also reply this RFC patch to this coverletter in case anyone wants > to have a discussion. Nevertheless, my exception is this series can be > merged first w/o the RFC patch. We can follow up the optimizations > later. > > This series is tagged v2, since it's a closer follow on to the RFC > patchset, which was posted before the single patch: > > https://lore.kernel.org/all/cover.1741778537.git.kai.huang@intel.com/ > > This series is based on today's tip/master. I'm on PTO for the next few days, so I'll try to review/test the SME related changes when I return. Thanks, Tom >