This is a note to let you know that I've just added the patch titled
of: fdt: Honor CONFIG_CMDLINE* even without /chosen node, take 2
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
of-fdt-honor-config_cmdline-even-without-chosen-node.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5eece547bd36776908d82ffb3ce1120ad84408d7
Author: Rob Herring <robh@xxxxxxxxxx>
Date: Tue Jan 3 12:00:32 2023 -0600
of: fdt: Honor CONFIG_CMDLINE* even without /chosen node, take 2
[ Upstream commit 064e32dc5b03114d0767893fecdaf7b5dfd8c286 ]
I do not read a strict requirement on /chosen node in either ePAPR or in
Documentation/devicetree. Help text for CONFIG_CMDLINE and
CONFIG_CMDLINE_EXTEND doesn't make their behavior explicitly dependent on
the presence of /chosen or the presense of /chosen/bootargs.
However the early check for /chosen and bailing out in
early_init_dt_scan_chosen() skips CONFIG_CMDLINE handling which is not
really related to /chosen node or the particular method of passing cmdline
from bootloader.
This leads to counterintuitive combinations (assuming
CONFIG_CMDLINE_EXTEND=y):
a) bootargs="foo", CONFIG_CMDLINE="bar" => cmdline=="foo bar"
b) /chosen missing, CONFIG_CMDLINE="bar" => cmdline==""
c) bootargs="", CONFIG_CMDLINE="bar" => cmdline==" bar"
Rework early_init_dt_scan_chosen() so that the cmdline config options are
always handled.
[commit msg written by Alexander Sverdlin]
Cc: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Tested-by: Geoff Levand <geoff@xxxxxxxxxxxxx>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
Link: https://lore.kernel.org/r/20230103-dt-cmdline-fix-v1-2-7038e88b18b6@xxxxxxxxxx
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 4f88e8bbdd27..f08b25195ae7 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -1163,18 +1163,32 @@ int __init early_init_dt_scan_chosen(char *cmdline)
if (node < 0)
node = fdt_path_offset(fdt, "/chosen@0");
if (node < 0)
- return -ENOENT;
+ /* Handle the cmdline config options even if no /chosen node */
+ goto handle_cmdline;
chosen_node_offset = node;
early_init_dt_check_for_initrd(node);
early_init_dt_check_for_elfcorehdr(node);
+ rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
+ if (rng_seed && l > 0) {
+ add_bootloader_randomness(rng_seed, l);
+
+ /* try to clear seed so it won't be found. */
+ fdt_nop_property(initial_boot_params, node, "rng-seed");
+
+ /* update CRC check value */
+ of_fdt_crc32 = crc32_be(~0, initial_boot_params,
+ fdt_totalsize(initial_boot_params));
+ }
+
/* Retrieve command line */
p = of_get_flat_dt_prop(node, "bootargs", &l);
if (p != NULL && l > 0)
strscpy(cmdline, p, min(l, COMMAND_LINE_SIZE));
+handle_cmdline:
/*
* CONFIG_CMDLINE is meant to be a default in case nothing else
* managed to set the command line, unless CONFIG_CMDLINE_FORCE
@@ -1195,18 +1209,6 @@ int __init early_init_dt_scan_chosen(char *cmdline)
pr_debug("Command line is: %s\n", (char *)cmdline);
- rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
- if (rng_seed && l > 0) {
- add_bootloader_randomness(rng_seed, l);
-
- /* try to clear seed so it won't be found. */
- fdt_nop_property(initial_boot_params, node, "rng-seed");
-
- /* update CRC check value */
- of_fdt_crc32 = crc32_be(~0, initial_boot_params,
- fdt_totalsize(initial_boot_params));
- }
-
return 0;
}
