Hi Lee,

FYI, there are new smatch warnings show up in

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched/numa
head:   7eaffe9d688041a66acac719aa7eaec23fb1f437
commit: 0719b9688bfedbc6ab12e863a0b2daf37d319f8d [20/35] mm/mpol: Add MPOL_MF_NOOP

  mm/mempolicy.c:2064 __mpol_equal() info: ignoring unreachable code.
+ mm/mempolicy.c:2426 mpol_parse_str() error: buffer overflow 'policy_modes' 5 <= 5

Need to define one more entry in policy_modes[] for fixing the bug.

vim +2426 mm/mempolicy.c

095f1fc4 (Lee Schermerhorn 2008-04-28  2410) 	int err = 1;
095f1fc4 (Lee Schermerhorn 2008-04-28  2411) 
095f1fc4 (Lee Schermerhorn 2008-04-28  2412) 	if (nodelist) {
095f1fc4 (Lee Schermerhorn 2008-04-28  2413) 		/* NUL-terminate mode or flags string */
095f1fc4 (Lee Schermerhorn 2008-04-28  2414) 		*nodelist++ = '\0';
71fe804b (Lee Schermerhorn 2008-04-28  2415) 		if (nodelist_parse(nodelist, nodes))
095f1fc4 (Lee Schermerhorn 2008-04-28  2416) 			goto out;
71fe804b (Lee Schermerhorn 2008-04-28  2417) 		if (!nodes_subset(nodes, node_states[N_HIGH_MEMORY]))
095f1fc4 (Lee Schermerhorn 2008-04-28  2418) 			goto out;
71fe804b (Lee Schermerhorn 2008-04-28  2419) 	} else
71fe804b (Lee Schermerhorn 2008-04-28  2420) 		nodes_clear(nodes);
71fe804b (Lee Schermerhorn 2008-04-28  2421) 
095f1fc4 (Lee Schermerhorn 2008-04-28  2422) 	if (flags)
095f1fc4 (Lee Schermerhorn 2008-04-28  2423) 		*flags++ = '\0';	/* terminate mode string */
095f1fc4 (Lee Schermerhorn 2008-04-28  2424) 
6f98f929 (Peter Zijlstra   2012-03-19  2425) 	for (mode = 0; mode < MPOL_MAX; mode++) {
345ace9c (Lee Schermerhorn 2010-05-24 @2426) 		if (!strcmp(str, policy_modes[mode])) {
095f1fc4 (Lee Schermerhorn 2008-04-28  2427) 			break;
095f1fc4 (Lee Schermerhorn 2008-04-28  2428) 		}
095f1fc4 (Lee Schermerhorn 2008-04-28  2429) 	}
6f98f929 (Peter Zijlstra   2012-03-19  2430) 	if (mode >= MPOL_MAX)
095f1fc4 (Lee Schermerhorn 2008-04-28  2431) 		goto out;
095f1fc4 (Lee Schermerhorn 2008-04-28  2432) 
71fe804b (Lee Schermerhorn 2008-04-28  2433) 	switch (mode) {
095f1fc4 (Lee Schermerhorn 2008-04-28  2434) 	case MPOL_PREFERRED:

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0-DAY kernel build testing backend         Open Source Technology Centre
Fengguang Wu, Yuanhan Liu                              Intel Corporation