diff options
author | Wladislav Wiebe <wladislav.kw@gmail.com> | 2013-08-12 13:06:53 +0200 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2015-02-16 11:32:50 +0900 |
commit | f80b1f865b8a901b293dec99685afa56b41c040b (patch) | |
tree | c8db7634c82757176f622e551a9397dd1ce41b85 | |
parent | ca25778ff3c90cd0489d599c66aa63671792ed8a (diff) |
of: fdt: fix memory initialization for expanded DT
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>
Cc: stable@vger.kernel.org
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
(cherry picked from commit 9e40127526e857fa3f29d51e83277204fbdfc6ba)
Signed-off-by: Mark Brown <broonie@kernel.org>
-rw-r--r-- | drivers/of/fdt.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 21123b8ee4d4..a1ebaecc8122 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); |