From: Simon Glass <s...@chromium.org>
Add a little more detail in a few of these comments.
Signed-off-by: Simon Glass <s...@chromium.org>
Suggested-by: David Gibson <da...@gibson.dropbear.id.au>
Message-Id: <20200302190255.51426-2-...@chromium.org>
Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
---
cpukit/dtc/libfdt/libfdt_internal.h | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/cpukit/dtc/libfdt/libfdt_internal.h
b/cpukit/dtc/libfdt/libfdt_internal.h
index 3201678cf6..7999f6a2d4 100644
--- a/cpukit/dtc/libfdt/libfdt_internal.h
+++ b/cpukit/dtc/libfdt/libfdt_internal.h
@@ -91,7 +91,9 @@ enum {
*
* With this assumption enabled, normal device trees produced by libfdt
* and the compiler should be handled safely. Malicious device trees and
- * complete garbage may cause libfdt to behave badly or crash.
+ * complete garbage may cause libfdt to behave badly or crash. Truncated
+ * device trees (e.g. those only partially loaded) can also cause
+ * problems.
*
* Note: Only checks that relate exclusively to the device tree itself
* (not the parameters passed to libfdt) are disabled by this
@@ -130,8 +132,15 @@ enum {
ASSUME_NO_ROLLBACK = 1 << 3,
/*
- * This assumes that the device tree components appear in the correct
- * order. As such it disables a check in fdt_open_into() and removes the
+ * This assumes that the device tree components appear in a 'convenient'
+ * order, i.e. the memory reservation block first, then the structure
+ * block and finally the string block.
+ *
+ * This order is not specified by the device-tree specification,
+ * but is expected by libfdt. The device-tree compiler always created
+ * device trees with this order.
+ *
+ * This assumption disables a check in fdt_open_into() and removes the
* ability to fix the problem there. This is safe if you know that the
* device tree is correctly ordered. See fdt_blocks_misordered_().
*/
--
2.31.1
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