x86/NUMA: correct off-by-1 in node map population

As it turns out populate_memnodemap() so far "relied" on
extract_lsb_from_nodes() setting memnodemapsize one too high in edge
cases. Correct the issue there as well, by changing "epdx" to be an
inclusive PDX and adjusting the respective relational operators.

While there also limit the scope of both related variables.

Fixes: b1f4b45d02ca ("x86/NUMA: correct off-by-1 in node map size calculation")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Release-acked-by: Henry Wang <Henry.Wang@arm.com>

diff --git a/xen/arch/x86/numa.c b/xen/arch/x86/numa.c
index 2c3c1c15fe8b4499f2e12259ddbdc45d3ec30920..322157fab7ca63ba5d3b9d1712b4d370ea2ac69c 100644 (file)
--- a/xen/arch/x86/numa.c
+++ b/xen/arch/x86/numa.c
@@ -65,15 +65,15 @@ int srat_disabled(void)
 static int __init populate_memnodemap(const struct node *nodes,
                                       int numnodes, int shift, nodeid_t *nodeids)
 {
-    unsigned long spdx, epdx;
     int i, res = -1;
 
     memset(memnodemap, NUMA_NO_NODE, memnodemapsize * sizeof(*memnodemap));
     for ( i = 0; i < numnodes; i++ )
     {
-        spdx = paddr_to_pdx(nodes[i].start);
-        epdx = paddr_to_pdx(nodes[i].end - 1) + 1;
-        if ( spdx >= epdx )
+        unsigned long spdx = paddr_to_pdx(nodes[i].start);
+        unsigned long epdx = paddr_to_pdx(nodes[i].end - 1);
+
+        if ( spdx > epdx )
             continue;
         if ( (epdx >> shift) >= memnodemapsize )
             return 0;
@@ -88,7 +88,7 @@ static int __init populate_memnodemap(const struct node *nodes,
                 memnodemap[spdx >> shift] = nodeids[i];
 
             spdx += (1UL << shift);
-        } while ( spdx < epdx );
+        } while ( spdx <= epdx );
         res = 1;
     }