Re: [PATCH] introduce kernel_execve function to replace __KERNEL_SYSCALLS__

[Paul Mackerras <paulus@samba.org>]

Arnd Bergmann writes:

> Iit turned out most of the architectures that already implement
> their own execve() call instead of using the _syscall3 function
> for it end up passing the return value of sys_execve down, 
> instead of setting errno.

I really don't like having an "errno" variable in the kernel.  What if
two processes are doing an execve concurrently?

Anyway, your patch returns the (positive) errno value here:

> +	WARN_ON(segment_eq(fs, USER_DS));
> +	ret = execve(filename, (char **)argv, (char **)envp);
> +	if (ret)
> +		ret = errno;
> +
> +	return ret;

but here we are testing for a negative value to mean error:

> -	if (execve("/sbin/shutdown", argv, envp) < 0) {
> +	if (kernel_execve("/sbin/shutdown", argv, envp) < 0) {

Paul.