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Peter Anvin" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 2026-09-14 23:03, Xin Li wrote: > >> On Sep 11, 2026, at 2:36 PM, Sohil Mehta wrote: >> >> I mainly rebased the patches to the latest kvm-x86/next branch and fixed >> a handful of issues reported during internal testing and basic AI >> reviews. I've avoided making any major code changes or commit message >> updates as this is the first iteration that I am posting. > > Thanks a lot for taking care of the patch series. > >> >> Going forward, based on the feedback, I'll rework the patches as needed. >> I've listed a few opens below that need additional discussion or >> clarification. I'm relatively new to the KVM subsystem, so please feel >> free to provide suggestions on the series structure, code organization >> as well as commit log clarity to smoothen the review process. > > I’ve been thinking about an optimization: because FRED drops most of the old > syscall MSRs (IA32_LSTAR/IA32_CSTAR/IA32_SFMASK), we should be able to omit > them from KVM's uret MSR tracking entirely as if host enables FRED (no matter > whether a guest uses FRED). > Yes, although they will need to be handled properly between VCPU switches, of course. -hpa