Re: [PATCH tip/core/rcu 1/4] rcutorture: Fix module unwind when bad torture_type specified

[Josh Triplett <josh@joshtriplett.org>]

On Tue, Oct 06, 2015 at 09:49:10AM -0700, Paul E. McKenney wrote:
> The rcutorture module has a list of torture types, and specifying a
> type not on this list is supposed to cleanly fail the module load.
> Unfortunately, the "fail" happens without the "cleanly".  This commit
> therefore adds the needed clean-up after an incorrect torture_type.
> 
> Reported-by: David Miller <davem@davemloft.net>
> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> Acked-by: David Miller <davem@davemloft.net>

After a careful review of rcu_torture_cleanup and the cur_ops->init()
functions to verify that the dire comment about not using "goto unwind"
doesn't actually apply (rcu_torture_cleanup *seems* to handle lack of
init), this seems fine.

Reviewed-by: Josh Triplett <josh@joshtriplett.org>

>  kernel/rcu/rcutorture.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
> index 77192953dee5..b74b56474e17 100644
> --- a/kernel/rcu/rcutorture.c
> +++ b/kernel/rcu/rcutorture.c
> @@ -1742,15 +1742,15 @@ rcu_torture_init(void)
>  		for (i = 0; i < ARRAY_SIZE(torture_ops); i++)
>  			pr_alert(" %s", torture_ops[i]->name);
>  		pr_alert("\n");
> -		torture_init_end();
> -		return -EINVAL;
> +		firsterr = -EINVAL;
> +		goto unwind;
>  	}
>  	if (cur_ops->fqs == NULL && fqs_duration != 0) {
>  		pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n");
>  		fqs_duration = 0;
>  	}
>  	if (cur_ops->init)
> -		cur_ops->init(); /* no "goto unwind" prior to this point!!! */
> +		cur_ops->init();
>  
>  	if (nreaders >= 0) {
>  		nrealreaders = nreaders;
> -- 
> 2.5.2
>