From: Matthew Dillon <dillon@apollo.backplane.com>
Date: Tue, 21 Oct 2014 06:08:50 +0000 (-0700)
Subject: kernel - Fix int/long truncation problem in rman_reserve_resource()
X-Git-Tag: v4.1.0~29
X-Git-Url: https://gitweb.dragonflybsd.org/~tuxillo/dragonfly.git/commitdiff_plain/fc4394d140be3e7dba4315d0af40b2efa433164e

kernel - Fix int/long truncation problem in rman_reserve_resource()

* Use ulmin/ulmax instead of min/max in three places, fixing a 32-bit
  truncation problem when setting up memory resources that caused our
  48-core opteron to panic.

* An earlier commit adjusting count values to be more correct revealed
  the bug.

* Fixes booting the kernel on our 48-core opteron w/128G of ram.
---

diff --git a/sys/kern/subr_rman.c b/sys/kern/subr_rman.c
index 75705440f7..386b654226 100644
--- a/sys/kern/subr_rman.c
+++ b/sys/kern/subr_rman.c
@@ -227,7 +227,7 @@ rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count,
 		rstart = ulmax(s->r_start, start);
 		rstart = (rstart + ((1ul << RF_ALIGNMENT(flags))) - 1) &
 		    ~((1ul << RF_ALIGNMENT(flags)) - 1);
-		rend = min(s->r_end, max(start + count - 1, end));
+		rend = ulmin(s->r_end, ulmax(start + count - 1, end));
 		DPRINTF(("truncated region: [%#lx, %#lx]; size %#lx (requested %#lx)\n",
 		       rstart, rend, (rend - rstart + 1), count));
 
@@ -326,8 +326,8 @@ rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count,
 			break;
 		if ((s->r_flags & flags) != flags)
 			continue;
-		rstart = max(s->r_start, start);
-		rend = min(s->r_end, max(start + count, end));
+		rstart = ulmax(s->r_start, start);
+		rend = ulmin(s->r_end, ulmax(start + count, end));
 		if (s->r_start >= start && s->r_end <= end
 		    && (s->r_end - s->r_start + 1) == count) {
 			rv = kmalloc(sizeof *rv, M_RMAN, M_NOWAIT | M_ZERO);
diff --git a/sys/platform/pc64/x86_64/nexus.c b/sys/platform/pc64/x86_64/nexus.c
index 39626b3244..058959db20 100644
--- a/sys/platform/pc64/x86_64/nexus.c
+++ b/sys/platform/pc64/x86_64/nexus.c
@@ -689,9 +689,13 @@ ram_attach(device_t dev)
 				    __func__, rid, error);
 			res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
 			    0);
-			if (res == NULL)
-				panic("%s: resource %d failed to attach",
-				    __func__, rid);
+			if (res == NULL) {
+				panic("%s: resource %d failed to "
+				      "attach 0x%016jx/%jd",
+				    __func__, rid,
+				    (intmax_t)smap->base,
+				    (intmax_t)smap->length);
+			}
 			rid++;
 		}
 		return (0);