Re: [PATCH 1/1] x86: Fix mcheck_init_device() to handle misc_register() correctly

Johan Wessfeldt
2011-03-04T21:38:37Z

On Fri, Mar 4, 2011 at 2:29 PM, J.P. Lacerda <jp.lacerda@codethink.co.uk> wrote:
> The return value for misc_register() was not being taken into account.
> Furthermore, if misc_register() fails, we must rollback any changes made by
> mcheck_init_device()
>
> Signed-off-by: J.P. Lacerda <jp.lacerda@codethink.co.uk>
> ---
>  arch/x86/kernel/cpu/mcheck/mce.c |   13 ++++++++++++-
>  1 files changed, 12 insertions(+), 1 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
> index d916183..20c2c44 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce.c
> @@ -2140,7 +2140,18 @@ static __init int mcheck_init_device(void)
>        }
>
>        register_hotcpu_notifier(&mce_cpu_notifier);
> -       misc_register(&mce_log_device);
> +       err = misc_register(&mce_log_device);
> +
> +       if (err) {
> +               unregister_hotcpu_notifier(&mce_cpu_notifier);
> +
> +               for_each_online_cpu(i) {
> +                       mce_remove_device(i);
> +               }
> +
> +               sysdev_class_unregister(&mce_sysclass);
> +               free_cpumask_var(mce_dev_initialized);
> +       }
>
>        return err;
>  }
> --
> 1.7.1
>
>
I want to thank J.P. Lacerda for pointing out an additional leak that I
missed in my first version. ie. calling free_cpumask_var(mce_dev_initialized).

Regards.
// Johan W.