On Thu, May 25, 2023 at 04:40:00PM -0700, Sathyanarayanan Kuppuswamy wrote: > Hi, > > On 5/25/23 3:58 PM, 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_tlb_flush_required() called after adjusting direct mapping and > > it converts the memory to shared. > > Do you mean .enc_status_change_finish() here? Isn't enc_tlb_flush_required() > called before adjusting the mapping? Yes, I copy-pasted wrong callback :/ -- Kiryl Shutsemau / Kirill A. Shutemov
