parse_args() is too unforgivable?

From: Oleg Nesterov
Date: Mon Aug 24 2015 - 14:34:00 EST


On 08/24, Oleg Nesterov wrote:
>
> I booted the kernel with the additional patch below, and nothing bad has
> happened,

Until I tried reboot it once with "locktorture.verbose=true" paramater.
It didn't boot.

This is because parse_args() just aborts after it hits the error, so other
arguments at the same initcall level are simply ignored.

Fixed by the patch below, but I simply can't believe nobody hit this (imo)
bug before.

Why does parse_args() do this?? I simply can't understand why parse_args()
adds more random and hard-to-understand problems if one of the args ("=true"
in this particular case) is wrong.

Yes, the patch below is probably oversimplified / incomplete but imho the
current behaviour is confusing. At least I was greatly confused ;) At least
(I think) it makes sense to let the user know that the rest of command line
was probably ignored.

Oleg.
---

--- a/kernel/params.c
+++ b/kernel/params.c
@@ -220,19 +220,19 @@ char *parse_args(const char *doing,
doing, param);

switch (ret) {
+ case 0:
+ break;
case -ENOENT:
pr_err("%s: Unknown parameter `%s'\n", doing, param);
- return ERR_PTR(ret);
+ break;
case -ENOSPC:
pr_err("%s: `%s' too large for parameter `%s'\n",
doing, val ?: "", param);
- return ERR_PTR(ret);
- case 0:
break;
default:
pr_err("%s: `%s' invalid for parameter `%s'\n",
doing, val ?: "", param);
- return ERR_PTR(ret);
+ break;
}
}


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