[PATCH] init/main.c: add warning when file specified in rdinit is inaccessible

[PATCH] init/main.c: add warning when file specified in rdinit is inaccessible

[Lillian Berry]

Avoid silently ignoring the initramfs when the file specified in rdinit
is not usable. This prints an error that clearly explains the issue
(file was not found, vs initramfs was not found).

Signed-off-by: Lillian Berry <lillian@star-ark.net>
---
 init/main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/init/main.c b/init/main.c
index 225a58279acd..f391f62864a6 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1593,6 +1593,8 @@ static noinline void __init kernel_init_freeable(void)
 	 * the work
 	 */
 	if (init_eaccess(ramdisk_execute_command) != 0) {
+		pr_warn("WARNING: rdinit=%s is inaccessible or not existing, ignoring\n",
+			ramdisk_execute_command);
 		ramdisk_execute_command = NULL;
 		prepare_namespace();
 	}
-- 
2.48.1

Re: [PATCH] init/main.c: add warning when file specified in rdinit is inaccessible

[Andrew Morton]

On Sun,  6 Jul 2025 18:51:41 +0000 Lillian Berry <lillian@star-ark.net> wrote:

> Avoid silently ignoring the initramfs when the file specified in rdinit
> is not usable. This prints an error that clearly explains the issue
> (file was not found, vs initramfs was not found).
> 
> Signed-off-by: Lillian Berry <lillian@star-ark.net>
> ---
>  init/main.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/init/main.c b/init/main.c
> index 225a58279acd..f391f62864a6 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -1593,6 +1593,8 @@ static noinline void __init kernel_init_freeable(void)
>  	 * the work
>  	 */
>  	if (init_eaccess(ramdisk_execute_command) != 0) {
> +		pr_warn("WARNING: rdinit=%s is inaccessible or not existing, ignoring\n",

"is inaccessible or does not exist", please.

Is the "WARNING: " needed?  It's pr_warn(), which implies that it's a warning.

It would be good to display the errno itself.  This way people can just
look up the numeric value so there's no need for this code to expand it
into text.

Perhaps the kernel should have an strerror() for this sort of thing,
but I don't think we do.  The required table is buried down in
net/9p/error.c, for some reason!

Re: [PATCH] init/main.c: add warning when file specified in rdinit is inaccessible

[Lillian Berry]

On Sun, Jul 6, 2025, at 10:13 PM, Andrew Morton wrote:
> "is inaccessible or does not exist", please.
Will update.

> Is the "WARNING: " needed?  It's pr_warn(), which implies that it's a warning.
I saw this on L486 (warn_bootconfig), but can remove.

> It would be good to display the errno itself. 
Yep! I'll add that.

Kindly,
Lillian