Merge tag 'stable/for-linus-4.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen bug fixes from David Vrabel:

 - fix a PV regression in 3.19.

 - fix a dom0 crash on hosts with large numbers of PIRQs.

 - prevent pcifront from disabling memory or I/O port access, which may
   trigger host crashes.

* tag 'stable/for-linus-4.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen-pciback: limit guest control of command register
  xen/events: avoid NULL pointer dereference in dom0 on large machines
  xen: Remove trailing semicolon from xenbus_register_frontend() definition
  x86/xen: correct bug in p2m list initialization

arch/x86/xen/p2m.c

@@ -563,7 +563,7 @@ static bool alloc_p2m(unsigned long pfn)
 		if (p2m_pfn == PFN_DOWN(__pa(p2m_missing)))
 			p2m_init(p2m);
 		else
-			p2m_init_identity(p2m, pfn);
+			p2m_init_identity(p2m, pfn & ~(P2M_PER_PAGE - 1));
 
 		spin_lock_irqsave(&p2m_update_lock, flags);