diff options
authorWladislav Wiebe <wladislav.kw@gmail.com>2013-08-12 13:06:53 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-08-29 09:47:37 -0700
commitabcdf87c25278b38972e41ca13fffc42b9d1f6f8 (patch)
parentce04434c6e596b264f92f39d3228883c60262b69 (diff)
of: fdt: fix memory initialization for expanded DT
commit 9e40127526e857fa3f29d51e83277204fbdfc6ba upstream. Already existing property flags are filled wrong for properties created from initial FDT. This could cause problems if this DYNAMIC device-tree functions are used later, i.e. properties are attached/detached/replaced. Simply dumping flags from the running system show, that some initial static (not allocated via kzmalloc()) nodes are marked as dynamic. I putted some debug extensions to property_proc_show(..) : .. + if (OF_IS_DYNAMIC(pp)) + pr_err("DEBUG: xxx : OF_IS_DYNAMIC\n"); + if (OF_IS_DETACHED(pp)) + pr_err("DEBUG: xxx : OF_IS_DETACHED\n"); when you operate on the nodes (e.g.: ~$ cat /proc/device-tree/*some_node*) you will see that those flags are filled wrong, basically in most cases it will dump a DYNAMIC or DETACHED status, which is in not true. (BTW. this OF_IS_DETACHED is a own define for debug purposes which which just make a test_bit(OF_DETACHED, &x->_flags) If nodes are dynamic kernel is allowed to kfree() them. But it will crash attempting to do so on the nodes from FDT -- they are not allocated via kzmalloc(). Signed-off-by: Wladislav Wiebe <wladislav.kw@gmail.com> Acked-by: Alexander Sverdlin <alexander.sverdlin@nsn.com> Signed-off-by: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 808be06bb67..118773751ea 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -392,6 +392,8 @@ static void __unflatten_device_tree(struct boot_param_header *blob,
mem = (unsigned long)
dt_alloc(size + 4, __alignof__(struct device_node));
+ memset((void *)mem, 0, size);
((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef);
pr_debug(" unflattening %lx...\n", mem);