069f9911a3
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4654 When building the Page State Change entries for a range of memory, it can happen that multiple calls to BuildPageStateBuffer() need to be made. If the size of the input work area passed to BuildPageStateBuffer() exceeds the number of entries that can be passed to the hypervisor using the GHCB shared buffer, the Page State Change VMGEXIT support will issue multiple VMGEXITs to process all entries in the buffer. However, it could be that the final VMGEXIT for each round of Page State Changes is only for a small number of entries and subsequent VMGEXITs may still be issued to handle the full range of memory requested. To maximize the number of entries processed during the Page State Change VMGEXIT, limit BuildPageStateBuffer() to not build entries that exceed the maximum number of entries that can be handled in a single Page State Change VMGEXIT. Cc: Ard Biesheuvel <ardb+tianocore@kernel.org> Cc: Erdem Aktas <erdemaktas@google.com> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Michael Roth <michael.roth@amd.com> Cc: Min Xu <min.m.xu@intel.com> Reviewed-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>