Hi! On 08/12/2013 01:00 PM, ext Wladislav Wiebe wrote: > 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@xxxxxxxxx> Acked-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxx> > --- > 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 6bb7cf2..b10ba00 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); > -- Best regards, Alexander Sverdlin. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html