On 02/10/2023 16:11, Roger Pau Monne wrote:
From: Jan Beulich <jbeul...@suse.com> The registration by virtual/linear address has downsides: At least on x86 the access is expensive for HVM/PVH domains. Furthermore for 64-bit PV domains the areas are inaccessible (and hence cannot be updated by Xen) when in guest-user mode, and for HVM guests they may be inaccessible when Meltdown mitigations are in place. (There are yet more issues.) In preparation of the introduction of new vCPU operations allowing to register the respective areas (one of the two is x86-specific) by guest-physical address, flesh out the map/unmap functions. Noteworthy differences from map_vcpu_info(): - areas can be registered more than once (and de-registered), - remote vCPU-s are paused rather than checked for being down (which in principle can change right after the check), - the domain lock is taken for a much smaller region. Signed-off-by: Jan Beulich <jbeul...@suse.com> Reviewed-by: Roger Pau Monné <roger....@citrix.com>
Reviewed-by: Julien Grall <jgr...@amazon.com> Cheers, -- Julien Grall
