x86/mm: update log-dirty bitmap when manipulating P2M

Just like for PV guests MMU_MACHPHYS_UPDATE implies marking of the
respective page as dirty, additions to a HVM guest's P2M should do so.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
[jb: backport limited to the new paging_mark_pfn_dirty() use]
master commit: 98fccdf0ac
master date: 2025-12-11 09:50:30 +0100

xen/arch/x86/mm/p2m.c

@@ -753,8 +753,11 @@ p2m_add_page(struct domain *d, gfn_t gfn, mfn_t mfn,
         if ( !p2m_is_grant(t) )
         {
             for ( i = 0; i < (1UL << page_order); i++ )
+            {
                 set_gpfn_from_mfn(mfn_x(mfn_add(mfn, i)),
                                   gfn_x(gfn_add(gfn, i)));
+                paging_mark_pfn_dirty(d, _pfn(gfn_x(gfn) + i));
+            }
         }
     }
     else