svn commit: r325860 - head/sbin/newfs

[Rodney W. Grimes]

> Author: emaste
> Date: Wed Nov 15 18:40:40 2017
> New Revision: 325860
> URL: https://svnweb.freebsd.org/changeset/base/325860
> 
> Log:
>   newfs: warn if newer than kernel
>   
>   Creating a UFS filesystem with a newfs newer than the running kernel,
>   and then mounting that filesystem, can lead to interesting failures.
>   
>   Add a safety belt to explicitly warn when newfs is newer than the
>   running kernel.

You should probably make the warning if (newer || older) as
either is likely to have interesting side effects, as are
mounting ufs file systems on different versions.

*Sigh*  why did not UFS grow a version number of its own
when things started to change other than UFS1 vs UFS2.


>   Reviewed by:	gjb, jhb, mckusick
>   Sponsored by:	The FreeBSD Foundation
>   Differential Revision:	https://reviews.freebsd.org/D12765
> 
> Modified:
>   head/sbin/newfs/newfs.c
> 
> Modified: head/sbin/newfs/newfs.c
> ==============================================================================
> --- head/sbin/newfs/newfs.c	Wed Nov 15 18:03:31 2017	(r325859)
> +++ head/sbin/newfs/newfs.c	Wed Nov 15 18:40:40 2017	(r325860)
> @@ -398,6 +398,10 @@ main(int argc, char *argv[])
>  		if (pp != NULL)
>  			pp->p_size *= secperblk;
>  	}
> +	if (getosreldate() < __FreeBSD_version) {
> +		warnx("%s is newer than the running kernel and may not be compatible",
> +		    getprogname());
> +	}
>  	mkfs(pp, special);
>  	ufs_disk_close(&disk);
>  	if (!jflag)
> 
> 

-- 
Rod Grimes                                                 rgrimes at freebsd.org