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Subject: Re: [PATCH] Avoid null-pointer access in w1/slaves/w1_therm
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Date: Tue, 10 Mar 2015 16:52:00 +0300
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Hi

10.03.2015, 02:09, "David Fries" <david@fries.net>:

> diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c
> index 1f11a20..39a9e6a 100644
> --- a/drivers/w1/slaves/w1_therm.c
> +++ b/drivers/w1/slaves/w1_therm.c
> @@ -59,9 +59,20 @@ MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS28EA00));
> šstatic int w1_strong_pullup = 1;
> šmodule_param_named(strong_pullup, w1_strong_pullup, int, 0);
>
> +struct w1_therm_family_data {
> + uint8_t rom[9];
> + struct mutex lock;
> +};

This approach will not scale to other w1 families, I would rather prefer solutions on w1 level,
not in particular drivers. What if we drop slave reference counter at all in favor of automatic sysfs device management?