While plausible to do what was intended based on the name of the flag (PGC_page_table), that name was misleading and is going to be changed. It marks page tables pages _having_ a shadow, not shadows of page table pages. The attempt also didn't cover the HAP case at all, and it constituted a potentially very long loop doing nothing when !SHADOW_PAGING. Instead leave a comment of what actually wants doing there (which then also may need to account for e.g. the risk of A/D bits becoming set behind our backs).
Signed-off-by: Jan Beulich <[email protected]> --- a/xen/arch/x86/tboot.c +++ b/xen/arch/x86/tboot.c @@ -177,29 +177,6 @@ static void update_iommu_mac(vmac_ctx_t #define is_page_in_use(page) \ (page_state_is(page, inuse) || page_state_is(page, offlining)) -static void update_pagetable_mac(vmac_ctx_t *ctx) -{ - unsigned long mfn; - - for ( mfn = 0; mfn < max_page; mfn++ ) - { - struct page_info *page = mfn_to_page(_mfn(mfn)); - - if ( !mfn_valid(_mfn(mfn)) ) - continue; - if ( is_page_in_use(page) && !is_special_page(page) ) - { - if ( page->count_info & PGC_page_table ) - { - void *pg = map_domain_page(_mfn(mfn)); - - vmac_update(pg, PAGE_SIZE, ctx); - unmap_domain_page(pg); - } - } - } -} - static void tboot_gen_domain_integrity(const uint8_t key[TB_KEY_SIZE], vmac_t *mac) { @@ -233,8 +210,7 @@ static void tboot_gen_domain_integrity(c } } - /* MAC all shadow page tables */ - update_pagetable_mac(&ctx); + /* TODO: MAC all shadow / HAP page tables */ *mac = vmac(NULL, 0, nonce, NULL, &ctx);
