Merge tag 'for-linus-5.16b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - a series to speed up the boot of Xen PV guests

 - some cleanups in Xen related code

 - replacement of license texts with the appropriate SPDX headers and
   fixing of wrong SPDX headers in Xen header files

 - a small series making paravirtualized interrupt masking much simpler
   and at the same time removing complaints of objtool

 - a fix for Xen ballooning hogging workqueues for too long

 - enablement of the Xen pciback driver for Arm

 - some further small fixes/enhancements

* tag 'for-linus-5.16b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (22 commits)
  xen/balloon: fix unused-variable warning
  xen/balloon: rename alloc/free_xenballooned_pages
  xen/balloon: add late_initcall_sync() for initial ballooning done
  x86/xen: remove 32-bit awareness from startup_xen
  xen: remove highmem remnants
  xen: allow pv-only hypercalls only with CONFIG_XEN_PV
  x86/xen: remove 32-bit pv leftovers
  xen-pciback: allow compiling on other archs than x86
  x86/xen: switch initial pvops IRQ functions to dummy ones
  x86/xen: remove xen_have_vcpu_info_placement flag
  x86/pvh: add prototype for xen_pvh_init()
  xen: Fix implicit type conversion
  xen: fix wrong SPDX headers of Xen related headers
  xen/pvcalls-back: Remove redundant 'flush_workqueue()' calls
  x86/xen: Remove redundant irq_enter/exit() invocations
  xen-pciback: Fix return in pm_ctrl_init()
  xen/x86: restrict PV Dom0 identity mapping
  xen/x86: there's no highmem anymore in PV mode
  xen/x86: adjust handling of the L3 user vsyscall special page table
  xen/x86: adjust xen_set_fixmap()
  ...