Merge branch 'in-3.1/bug.fixes' into stable/for-linus-3.3.rebased

Merge branch 'in-3.1/bug.fixes' into stable/for-linus-3.3.rebased

* in-3.1/bug.fixes:
  x86/paravirt: PTE updates in k(un)map_atomic need to be synchronous, regardless of lazy_mmu mode.
  xen/i386: follow-up to "replace order-based range checking of M2P table by linear one"
  xen/irq: Alter the locking to use a mutex instead of a spinlock.
  xen/e820: if there is no dom0_mem=, don't tweak extra_pages.
  Revert "xen/e820: if there is no dom0_mem=, don't tweak extra_pages."
  xen/e820: if there is no dom0_mem=, don't tweak extra_pages.
  xen: disable PV spinlocks on HVM
  xen/smp: Warn user why they keel over - nosmp or noapic and what to use instead.
  xen: x86_32: do not enable iterrupts when returning from exception in interrupt context
  xen: use maximum reservation to limit amount of usable RAM
  xen: Do not enable PV IPIs when vector callback not present
  xen/x86: replace order-based range checking of M2P table by linear one
  xen: Fix misleading WARN message at xen_release_chunk
  xen: Fix printk() format in xen/setup.c
  xen/grant: Fix compile warning.
  xen:pvhvm: Modpost section mismatch fix