kernel 4.4.0 OOPS: "x86/mm: Found insecure W+X mapping at address ..."

[suse.dev@fea.st]

I'm booting kernel 4.4.x + xen 4.6 -- recently upgraded from kernel 4.3.x,

	uname -rm
		4.4.0-3.g0567b9b-default x86_64

kernel pkgs are from opensuse repos @

	http://download.opensuse.org/repositories/Kernel:/stable/standard

Post-upgrade, I'm seeing the following OOPS on boot; apparently non-fatal, as the system _does_ subsequently complete boot.

There are a couple of prior mentions on LKML, as yet unaddressed

	https://lkml.org/lkml/2015/11/7/57
	https://lkml.org/lkml/2016/1/19/134

as well as on Xen ML

	http://lists.xen.org/archives/html/xen-devel/2015-11/msg00514.html

Here's the trace,

	Jan 20 17:43:49 x001 kernel: ------------[ cut here ]------------
	Jan 20 17:43:49 x001 kernel: WARNING: CPU: 0 PID: 1 at ../arch/x86/mm/dump_pagetables.c:225 note_page+0x5e1/0x780()
	Jan 20 17:43:49 x001 kernel: x86/mm: Found insecure W+X mapping at address ffff880000000000/0xffff880000000000
	Jan 20 17:43:49 x001 kernel: Modules linked in:
	Jan 20 17:43:49 x001 kernel: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.0-3.g0567b9b-default #1
	Jan 20 17:43:49 x001 kernel: Hardware name: Supermicro X10SAT/X10SAT, BIOS 3.0 05/26/2015
	Jan 20 17:43:49 x001 kernel:  ffffffff81a44e20 ffff880169f57d58 ffffffff8137f639 ffff880169f57da0
	Jan 20 17:43:49 x001 kernel:  ffff880169f57d90 ffffffff8107d132 ffff880169f57e98 0010000000000027
	Jan 20 17:43:49 x001 kernel:  0000000000000004 0000000000000000 0000000000000000 ffff880169f57df0
	Jan 20 17:43:49 x001 kernel: Call Trace:
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8101a095>] try_stack_unwind+0x175/0x190
	Jan 20 17:43:49 x001 kernel:  [<ffffffff81018fe9>] dump_trace+0x69/0x3a0
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8101a0fb>] show_trace_log_lvl+0x4b/0x60
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8101942c>] show_stack_log_lvl+0x10c/0x180
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8101a195>] show_stack+0x25/0x50
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8137f639>] dump_stack+0x4b/0x72
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8107d132>] warn_slowpath_common+0x82/0xc0
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8107d1bc>] warn_slowpath_fmt+0x4c/0x50
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8106e2b1>] note_page+0x5e1/0x780
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8106e73e>] ptdump_walk_pgd_level_core+0x2ee/0x420
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8106e8a7>] ptdump_walk_pgd_level_checkwx+0x17/0x20
	Jan 20 17:43:49 x001 kernel:  [<ffffffff81064b2f>] mark_rodata_ro+0xef/0x100
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8169d72d>] kernel_init+0x1d/0xe0
	Jan 20 17:43:49 x001 kernel:  [<ffffffff816aa40f>] ret_from_fork+0x3f/0x70
	Jan 20 17:43:49 x001 kernel: DWARF2 unwinder stuck at ret_from_fork+0x3f/0x70
	Jan 20 17:43:49 x001 kernel:
	Jan 20 17:43:49 x001 kernel: Leftover inexact backtrace:
	Jan 20 17:43:49 x001 kernel:  [<ffffffff8169d710>] ? rest_init+0x90/0x90
	Jan 20 17:43:49 x001 kernel: ---[ end trace 3cc91a447d30cdcf ]---
	Jan 20 17:43:49 x001 kernel: x86/mm: Checked W+X mappings: FAILED, 4090 W+X pages found.

No sure what additional info's helpful; let me know specific, and I can provide.

Thanks.

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