[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] pagetable RO
>>> On 11.10.13 at 08:30, åæ<zhangzhi2022@xxxxxxxxxxx> wrote: > Say, the sub-op: MMU_NORMAL_PT_UPDATE, > if the page that ptr of struct mmu_update points to is PGT_l2_page_table, > then > the address part of val of struct mmu_update points > to a page, which is PGT_l1_page_table. > However, I couldn't find the protections for this PGT_l1_page_table > page in the do_mmu_update, is it already set as read-only > before launching MMU_UPDATE hypercall? Of course - a page can't be PGT_l1_page_table when there still is some writable mapping around. So for an L2 entry update it is sufficient to verify that all contained L1 entries point to R/O pages (and transition them to PGT_l1_page_table if they aren't already). Jan _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |