xen/arm: fix duplicate /reserved-memory node in Dom0

In case there is a /reserved-memory node already present in the host
dtb, current Xen codes would create yet another /reserved-memory node
when the static shared memory feature is enabled and static shared
memory regions are present.
This would result in an incorrect device tree generation and hwdom
would not be able to detect the static shared memory region.

Avoid this issue by checking the presence of the /reserved-memory
node and appending the nodes instead of generating a duplicate
/reserved-memory.

Make make_shm_memory_node externally visible and rename it to
make_shm_resv_memory_node to make clear it produces childs for
/reserved-memory.

Signed-off-by: Penny Zheng <penny.zheng@arm.com>
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 0cc39b0bd7bb5c139b515041afb0114fd92fe5a3..68532ddc084cbf9ef304c349fab75da25136b776 100644 (file)
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -1640,6 +1640,7 @@ static int __init handle_node(struct domain *d, struct kernel_info *kinfo,
         DT_MATCH_PATH("/hypervisor"),
         { /* sentinel */ },
     };
+    static __initdata bool res_mem_node_found = false;
     struct dt_device_node *child;
     int res, i, nirq, irq_id;
     const char *name;
@@ -1734,6 +1735,19 @@ static int __init handle_node(struct domain *d, struct kernel_info *kinfo,
     if ( res )
         return res;
 
+    if ( dt_node_path_is_equal(node, "/reserved-memory") )
+    {
+        res_mem_node_found = true;
+        /*
+         * Avoid duplicate /reserved-memory nodes in Device Tree, so add the
+         * static shared memory nodes there.
+         */
+        res = make_shm_resv_memory_node(kinfo, dt_n_addr_cells(node),
+                                        dt_n_size_cells(node));
+        if ( res )
+            return res;
+    }
+
     for ( child = node->child; child != NULL; child = child->sibling )
     {
         res = handle_node(d, kinfo, child, p2mt);
@@ -1786,9 +1800,12 @@ static int __init handle_node(struct domain *d, struct kernel_info *kinfo,
                 return res;
         }
 
-        res = make_resv_memory_node(kinfo, addrcells, sizecells);
-        if ( res )
-            return res;
+        if ( !res_mem_node_found )
+        {
+            res = make_resv_memory_node(kinfo, addrcells, sizecells);
+            if ( res )
+                return res;
+        }
     }
 
     res = fdt_end_node(kinfo->fdt);

diff --git a/xen/arch/arm/include/asm/static-shmem.h b/xen/arch/arm/include/asm/static-shmem.h
index 2e8b138eb9898004467c21c5366d62c32eb7ae8f..7495a91e7a3194ba3ff69018cc86da0ee3eab45e 100644 (file)
--- a/xen/arch/arm/include/asm/static-shmem.h
+++ b/xen/arch/arm/include/asm/static-shmem.h
@@ -34,6 +34,9 @@ int remove_shm_from_rangeset(const struct kernel_info *kinfo,
 int remove_shm_holes_for_domU(const struct kernel_info *kinfo,
                               struct membanks *ext_regions);
 
+int make_shm_resv_memory_node(const struct kernel_info *kinfo, int addrcells,
+                              int sizecells);
+
 #else /* !CONFIG_STATIC_SHM */
 
 static inline int make_resv_memory_node(const struct kernel_info *kinfo,
@@ -77,6 +80,12 @@ static inline int remove_shm_holes_for_domU(const struct kernel_info *kinfo,
     return 0;
 }
 
+static inline int make_shm_resv_memory_node(const struct kernel_info *kinfo,
+                                            int addrcells, int sizecells)
+{
+    return 0;
+}
+
 #endif /* CONFIG_STATIC_SHM */
 
 #endif /* __ASM_STATIC_SHMEM_H_ */

diff --git a/xen/arch/arm/static-shmem.c b/xen/arch/arm/static-shmem.c
index 12e2df93991549fc613c9a9c920277fb6915a78b..c85f60dd1bf7ead41f91ffa6ed643ba93fc7f6ac 100644 (file)
--- a/xen/arch/arm/static-shmem.c
+++ b/xen/arch/arm/static-shmem.c
@@ -297,8 +297,8 @@ int __init process_shm(struct domain *d, struct kernel_info *kinfo,
     return 0;
 }
 
-static int __init make_shm_memory_node(const struct kernel_info *kinfo,
-                                       int addrcells, int sizecells)
+int __init make_shm_resv_memory_node(const struct kernel_info *kinfo,
+                                     int addrcells, int sizecells)
 {
     const struct membanks *mem = &kinfo->shm_mem.common;
     void *fdt = kinfo->fdt;
@@ -306,7 +306,7 @@ static int __init make_shm_memory_node(const struct kernel_info *kinfo,
     int res = 0;
 
     if ( mem->nr_banks == 0 )
-        return -ENOENT;
+        return 0;
 
     /*
      * For each shared memory region, a range is exposed under
@@ -544,7 +544,7 @@ int __init make_resv_memory_node(const struct kernel_info *kinfo, int addrcells,
     if ( res )
         return res;
 
-    res = make_shm_memory_node(kinfo, addrcells, sizecells);
+    res = make_shm_resv_memory_node(kinfo, addrcells, sizecells);
     if ( res )
         return res;