4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tobias Wolf <dev-NTEO@xxxxxxxxx> commit 3ec754410cb3e931a6c4920b1a150f21a94a2bf4 upstream. An empty __dtb_start to __dtb_end section might result in initial_boot_params being null for arch/mips/ralink. This showed that the boot process hangs indefinitely in of_scan_flat_dt(). Signed-off-by: Tobias Wolf <dev-NTEO@xxxxxxxxx> Cc: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxx Patchwork: https://patchwork.linux-mips.org/patch/14605/ Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/of/fdt.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -741,9 +741,12 @@ int __init of_scan_flat_dt(int (*it)(uns const char *pathp; int offset, rc = 0, depth = -1; - for (offset = fdt_next_node(blob, -1, &depth); - offset >= 0 && depth >= 0 && !rc; - offset = fdt_next_node(blob, offset, &depth)) { + if (!blob) + return 0; + + for (offset = fdt_next_node(blob, -1, &depth); + offset >= 0 && depth >= 0 && !rc; + offset = fdt_next_node(blob, offset, &depth)) { pathp = fdt_get_name(blob, offset, NULL); if (*pathp == '/')
