[RFC PATCH] OF: fix of_find_node_by_path() assumption that of_allnodes is root

From: Frank Rowand
Date: Fri Jun 13 2014 - 01:53:49 EST


From: Frank Rowand <frank.rowand@xxxxxxxxxxxxxx>

Pantelis Antoniou reports that of_find_node_by_path() is borked because
of_allnodes is not guaranteed to contain the root of the tree after using
any of the dynamic update functions because some other nodes ends up as
of_allnodes.

Fixes: c22e650e66b8 of: Make of_find_node_by_path() handle /aliases

Signed-off-by: Frank Rowand <frank.rowand@xxxxxxxxxxxxxx>
---


Pantelis,

Can you test whether the problem you reported in irc?

This patch has not been tested, not even compile tested.


drivers/of/base.c | 8 6 + 2 - 0 !
1 file changed, 6 insertions(+), 2 deletions(-)

Index: b/drivers/of/base.c
===================================================================
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1948,6 +1948,9 @@ int of_reconfig_notify(unsigned long act

/**
* of_attach_node - Plug a device node into the tree and global list.
+ *
+ * Put the device node after of_allnodes in the global list so that
+ * of_allnodes remains the root.
*/
int of_attach_node(struct device_node *np)
{
@@ -1958,11 +1961,12 @@ int of_attach_node(struct device_node *n
if (rc)
return rc;

+ BUG_ON(!of_allnodes);
raw_spin_lock_irqsave(&devtree_lock, flags);
np->sibling = np->parent->child;
- np->allnext = of_allnodes;
+ np->allnext = of_allnodes->allnext;
np->parent->child = np;
- of_allnodes = np;
+ of_allnodes->allnext = np;
of_node_clear_flag(np, OF_DETACHED);
raw_spin_unlock_irqrestore(&devtree_lock, flags);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/