Backport suggestions for Xen 4.4

[Andrew Cooper <andrew.cooper3@citrix.com>]

Hello,

Some further backport suggestions, from the XenServer patch queue.

Xen bugfixes:
* 415738e "x86/traps: make panic and reboot paths safe during early boot"
* d4f88fc "make the main trap handlers safe for use early during Xen boot"
** including "\n" fix for #MC handler from b30d333
* 92009d3 "x86/boot: correct CR4 setup on APs"

I would also consider 07884c9 "x86/amd: protect set_cpuidmask() against
#GP faults" a bugfix, but it depends on e74de9c and 7c6c8cc, the former
of which is far closer to a new feature than a bugfixes. 


Xen non-bugfix suggestions:
* d8af81a "x86/nmi: remove spurious local_irq_enable from
check_nmi_watchdog()"
* f64b190 "x86/nmi: be less verbose when testing the NMI watchdog"
* 11dba84 "x86/traps: do not inline do_trap() into 10 different handlers"
* 3385bf3 "x86: Intel CPU family update"


Toolstack bugfixes:
* 0e94de8 "tools/libxc: Issue individual DPRINTF()s rather than
multiline ones."
* d752158 "tools/pygrub: Fix error handling if no valid partitions are
found"
* 0c12e5b "tools/pygrub: Fix extlinux when /boot is a separate partition
from /"
* 84acc84 "libxc: Protect xc_domain_resume from clobbering domain registers"
* e86539a "libxc: check return values on mmap() and madvise() on
xc_alloc_hypercall_buffer()"
* 66f8c63 "tools/libxc: Annotate xc_osdep_log with __attribute__((format))"
* f1f009a "tools/libxc: Annotate xc_report_error with
__attribute__((format))"
** This patch applies cleanly, but doesn't compile cleanly due to other
xc_report_error() printf mismatches in 4.4.  The issues and fixes are
all obvious.


Toolstack non-bugfix suggestions:
* e927d4b "tools/mfndump: Avoid unintentional NULL dereference"
* 42e896b "tools/xenstore: Fix memory leaks in the client"
* dd7317a "libxl/save-helper: Code motion of logging functions"
* 82774ac "tools/libxl: Improvements to libxl-save-helper when using
valgrind"


Thanks,

~Andrew