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> >> + if ( unlikely(exit_reason & VMX_EXIT_REASONS_BUS_LOCK) ) > >> + { > >> + /* > >> + * Delivery of Bus Lock VM exit was pre-empted by a higher priority VM > >> + * exit. > >> + */ > >> + exit_reason &= ~VMX_EXIT_REASONS_BUS_LOCK; > >> + if ( exit_reason != EXIT_REASON_BUS_LOCK ) > >> + perfc_incr(buslock); > >> + } > > > > I know this post-dates you posting v2, but given the latest update from > > Intel, VMX_EXIT_REASONS_BUS_LOCK will be set on all exits. > > Mind me asking what "latest update" you're referring to? Neither SDM nor > ISE have seen a recent update, afaict. After Andrew's request we got in touch with Intel regarding whether VMX_EXIT_REASONS_BUS_LOCK is set when exit_reason == EXIT_REASON_BUS_LOCK, and they will update the ISE to contain: "the bit 26 in the exit-reason field will always be set on VM exits due to bus locks." So I will apply the changes requested by Andrew to match this behavior. Thanks, Roger.