smsc/xpmem: retry with requested if aligned range cannot be mapped

The aligned range computed in mca_smsc_xpmem_map_peer_region may reach past the end of the stack, which may cause the mapping to fail. Retrying with the requested upper bound has a better chance to succeed. Signed-off-by: Joseph Schuchart <[email protected]>
open-mpi · Mar 16, 2022 · ae71d72 · ae71d72
1 parent 1440592
commit ae71d72
Showing 1 changed file with 9 additions and 3 deletions.
diff --git a/opal/mca/smsc/xpmem/smsc_xpmem_module.c b/opal/mca/smsc/xpmem/smsc_xpmem_module.c
@@ -157,8 +157,14 @@ void *mca_smsc_xpmem_map_peer_region(mca_smsc_endpoint_t *endpoint, uint64_t fla
 
             reg->rcache_context = xpmem_attach(xpmem_addr, bound - base, NULL);
             if (OPAL_UNLIKELY((void *) -1 == reg->rcache_context)) {
-                OBJ_RELEASE(reg);
-                return NULL;
+                /* retry with the provided range as the upper bound */
+                bound = (uintptr_t)remote_ptr + size;
+                reg->bound = (unsigned char *) bound;
+                reg->rcache_context = xpmem_attach(xpmem_addr, bound - base, NULL);
+                if (OPAL_UNLIKELY((void *) -1 == reg->rcache_context)) {
+                    OBJ_RELEASE(reg);
+                    return NULL;
+                }
             }
 
             opal_memchecker_base_mem_defined(reg->rcache_context, bound - base);
@@ -307,5 +313,5 @@ mca_smsc_xpmem_module_t mca_smsc_xpmem_module = {
         .copy_from = mca_smsc_xpmem_copy_from,
         .map_peer_region = mca_smsc_xpmem_map_peer_region,
         .unmap_peer_region = mca_smsc_xpmem_unmap_peer_region,
-    }, 
+    },
 };