drivers/of: Fix build warning in populate_node()
Function populate_node() is used to unflatten FDT blob to device
tree. It supports maximal 64 level of device nodes. There is one
array @fpsizes[64] tracking the full name length of last unflattened
device node in the corresponding level (index of element in the
array - 1). Build warning is seen with CONFIG_FRAME_WARN=1024 like
below on ARM64 as Geert reported. The issue can be reproduced on
PPC64 as well.
$ make drivers/of/fdt.o
drivers/of/fdt.c:443:1: warning: the frame size of 1136 bytes is \
larger than 1024 bytes [-Wframe-larger-than=]
This changes the data type of @fpsizes[i] from "unsigned long" to
"unsigned int" to avoid the build warning. The return value type
of populate_node() and its @fpsize argument is adjusted accordingly.
With this applied, 256 bytes saved from the stack frame on ARM64 and
PPC64 platforms and the above warning isn't seen.
Fixes: 50800082f176 ("drivers/of: Avoid recursively calling unflatten_dt_node()")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index b352f67..14f2f8c 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -264,13 +264,13 @@
*pprev = NULL;
}
-static unsigned long populate_node(const void *blob,
- int offset,
- void **mem,
- struct device_node *dad,
- unsigned long fpsize,
- struct device_node **pnp,
- bool dryrun)
+static unsigned int populate_node(const void *blob,
+ int offset,
+ void **mem,
+ struct device_node *dad,
+ unsigned int fpsize,
+ struct device_node **pnp,
+ bool dryrun)
{
struct device_node *np;
const char *pathp;
@@ -397,7 +397,7 @@
struct device_node *root;
int offset = 0, depth = 0;
#define FDT_MAX_DEPTH 64
- unsigned long fpsizes[FDT_MAX_DEPTH];
+ unsigned int fpsizes[FDT_MAX_DEPTH];
struct device_node *nps[FDT_MAX_DEPTH];
void *base = mem;
bool dryrun = !base;