Re: [lm-sensors] [PATCH] x86/hwmon: fix module init for hotplug-but-no-device-found case

[Chen Gong <gong.chen@linux.intel.com>]

于 9/13/2010 6:05 PM, Jan Beulich 写道:
> In commit 0dca94baeab4a1a514841b0a4c8e3a51dfb4d5ae the call to
> platform_driver_unregister() was made conditional upon !HOTPLUG_CPU,
> but the return value from coretemp_init() was left to indicate an
> error. This isn't correct, as the negative return value indicates to
> the module loader that initialization failed, which isn't intended

only !HOTPLUG_CPU can remove the driver. That is what we need to do 
because under the hotplug condition, we need to consider those "offline"
cpus. I don't understand what you are afraid. Can you give me a scinario ?

> here and results in dangling pointers.
>
> Signed-off-by: Jan Beulich<jbeulich@novell.com>
> Cc: Chen Gong<gong.chen@linux.intel.com>
>
> ---
>   drivers/hwmon/coretemp.c |    5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
>
> --- linux-2.6.36-rc4/drivers/hwmon/coretemp.c	2010-09-13 08:45:02.000000000 +0200
> +++ 2.6.36-rc4-x86-coretemp-hotplug-init-return/drivers/hwmon/coretemp.c	2010-09-03 17:54:14.000000000 +0200
> @@ -541,16 +541,19 @@ static int __init coretemp_init(void)
>   				" has no thermal sensor.\n", c->x86_model);
>   		}
>   	}
> +
> +#ifndef CONFIG_HOTPLUG_CPU
>   	if (list_empty(&pdev_list)) {
>   		err = -ENODEV;
>   		goto exit_driver_unreg;
>   	}
> +#endif
>
>   	register_hotcpu_notifier(&coretemp_cpu_notifier);
>   	return 0;
>
> -exit_driver_unreg:
>   #ifndef CONFIG_HOTPLUG_CPU
> +exit_driver_unreg:
>   	platform_driver_unregister(&coretemp_driver);
>   #endif
>   exit:
>
>
>
>