On 5/26/23 05:02, Kirill A. Shutemov wrote: > Touching privately mapped GPA that is not properly converted to private > with MapGPA and accepted leads to unrecoverable exit to VMM. > > load_unaligned_zeropad() can touch memory that is not owned by the > caller, but just happened to next after the owned memory. > This load_unaligned_zeropad() behaviour makes it important when kernel > asks VMM to convert a GPA from shared to private or back. Kernel must > never have a page mapped into direct mapping (and aliases) as private > when the GPA is already converted to shared or when GPA is not yet > converted to private. > > guest.enc_status_change_prepare() called before adjusting direct mapping > and therefore it is responsible for converting the memory to private. > > guest.enc_status_change_finish() called after adjusting direct mapping > and it converts the memory to shared. > > It is okay to have a shared mapping of memory that is not converted > properly. handle_mmio() knows how to deal with load_unaligned_zeropad() > stepping on it. Yeah, as other said, the changelog grammar here is a bit funky. Can you fix it up and resend, please?
