Section "J.2 Undefined behavior" of n1570 includes:
* Pointers that do not point to the same aggregate or union (nor just
beyond the same array object) are compared using relational
operators (6.5.8).
I think that's what's happening when using RB trees in subr_hibernate.c.
subr_pool.c fixes this issue by casting the address to vaddr_t. Diff
to do the same in subr_hibernate.c below.
Index: sys/kern/subr_hibernate.c
===================================================================
RCS file: /cvs/src/sys/kern/subr_hibernate.c,v
retrieving revision 1.116
diff -u -p -r1.116 subr_hibernate.c
--- sys/kern/subr_hibernate.c 4 May 2015 02:18:05 -0000 1.116
+++ sys/kern/subr_hibernate.c 31 Aug 2016 08:35:53 -0000
@@ -156,7 +156,10 @@ hibernate_sort_ranges(union hibernate_in
static __inline int
hibe_cmp(struct hiballoc_entry *l, struct hiballoc_entry *r)
{
- return l < r ? -1 : (l > r);
+ vaddr_t vl = (vaddr_t)l;
+ vaddr_t vr = (vaddr_t)r;
+
+ return vl < vr ? -1 : (vl > vr);
}
RB_PROTOTYPE(hiballoc_addr, hiballoc_entry, hibe_entry, hibe_cmp)
--
Michal Mazurek
