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From: Richard Weinberger <richard@nod.at>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
	a.p.zijlstra@chello.nl, mingo@elte.hu, xiyou.wangcong@gmail.com
Subject: Re: [PATCH] init: Warn on non-existent rdinit
Date: Thu, 05 Jan 2012 22:45:29 +0100	[thread overview]
Message-ID: <4F0619F9.8010505@nod.at> (raw)
In-Reply-To: <m14nw9c1me.fsf@fess.ebiederm.org>

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Am 05.01.2012 21:53, schrieb Eric W. Biederman:
> Richard Weinberger <richard@nod.at> writes:
> 
>> Such a warning would have saved me some time...
>> Hopefully this printk() saves someone else's time. :-)
> 
> The warning is wrong if you are not using an initramfs or an initial
> ramdisk.

Gnah, you're so right.
I did not test it without a ramdisk.

> I expect what you want is something like:
> 
> diff --git a/init/main.c b/init/main.c
> index 217ed23..8d53d28 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -830,10 +830,11 @@ static int __init kernel_init(void * unused)
>          * the work
>          */
>  
> -       if (!ramdisk_execute_command)
> +       if (!ramdisk_execute_command &&
> +           (sys_access((const char __user *)"/init", 0) == 0))
>                 ramdisk_execute_command = "/init";
>  
> -       if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
> +       if (!ramdisk_execute_command) {
>                 ramdisk_execute_command = NULL;
>                 prepare_namespace();
>         }

Why ramdisk_execute_command = NULL; in the !ramdisk_execute_command case?

> 
> That way we don't clear ramdisk_execute_command if it was set and
> we complain if we attempt exec the ramdisk_execute_command.

If "/init" does not exist we still don't get a warning.

Thanks,
//richard



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  reply	other threads:[~2012-01-05 21:45 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-05 18:56 [PATCH] init: Warn on non-existent rdinit Richard Weinberger
2012-01-05 20:53 ` Eric W. Biederman
2012-01-05 21:45   ` Richard Weinberger [this message]
2012-01-05 22:00     ` Eric W. Biederman
2012-01-05 22:03       ` Richard Weinberger

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