> + argv4 = kzalloc(sizeof(*argv4) * (2 * num_of_ranges + 2 + 1), GFP_KERNEL);
> + if (!argv4)
> + return -ENOMEM;
> +
> + argv4[arg_idx].package.type = ACPI_TYPE_PACKAGE;
> + argv4[arg_idx].package.count = 2 + 2 * num_of_ranges;
> + argv4[arg_idx++].package.elements = &argv4[1];
> + argv4[arg_idx].integer.type = ACPI_TYPE_INTEGER;
> + argv4[arg_idx++].integer.value = num_of_ranges;
> + argv4[arg_idx].integer.type = ACPI_TYPE_INTEGER;
> + argv4[arg_idx++].integer.value = action;
There is a lot of magic numbers in that kzalloc. It is being used as
an array, kcalloc() would be a good start to make it more readable.
Can some #define's be used to explain what the other numbers mean?
> + /*
> + * Bit 0 indicates whether there's support for any functions other than
> + * function 0.
> + */
Please make use of the BIT macro to give the different bits
informative names.
> + if ((mask & 0x1) && (mask & funcs) == funcs)
> + return true;
> +
> + return false;
> +}
> +
> +int acpi_amd_wbrf_retrieve_exclusions(struct device *dev,
> + struct wbrf_ranges_out *out)
> +{
> + struct acpi_device *adev = ACPI_COMPANION(dev);
> + union acpi_object *obj;
> +
> + if (!adev)
> + return -ENODEV;
> +
> + obj = acpi_evaluate_wbrf(adev->handle,
> + WBRF_REVISION,
> + WBRF_RETRIEVE);
> + if (!obj)
> + return -EINVAL;
> +
> + WARN(obj->buffer.length != sizeof(*out),
> + "Unexpected buffer length");
> + memcpy(out, obj->buffer.pointer, obj->buffer.length);
You WARN, and then overwrite whatever i passed the end of out? Please
at least use min(obj->buffer.length, sizeof(*out)), but better still:
if (obj->buffer.length != sizeof(*out)) {
dev_err(dev, "BIOS FUBAR, ignoring wrong sized WBRT information");
return -EINVAL;
}
> +#if defined(CONFIG_WBRF_GENERIC)
> static struct exclusion_range_pool wbrf_pool;
>
> static int _wbrf_add_exclusion_ranges(struct wbrf_ranges_in *in)
> @@ -89,6 +92,7 @@ static int _wbrf_retrieve_exclusion_ranges(struct wbrf_ranges_out *out)
>
> return 0;
> }
> +#endif
I was expecting you would keep these tables, and then call into the
BIOS as well. Having this table in debugfs seems like a useful thing
to have for debugging the BIOS.
> +#ifdef CONFIG_WBRF_AMD_ACPI
> +#else
> +static inline bool
> +acpi_amd_wbrf_supported_consumer(struct device *dev) { return false; }
> +static inline bool
> +acpi_amd_wbrf_supported_producer(struct device *dev) {return false; }
> +static inline int
> +acpi_amd_wbrf_remove_exclusion(struct device *dev,
> + struct wbrf_ranges_in *in) { return -ENODEV; }
> +static inline int
> +acpi_amd_wbrf_add_exclusion(struct device *dev,
> + struct wbrf_ranges_in *in) { return -ENODEV; }
> +static inline int
> +acpi_amd_wbrf_retrieve_exclusions(struct device *dev,
> + struct wbrf_ranges_out *out) { return -ENODEV; }
Do you actually need these stub versions?
Andrew
[AMD Official Use Only - General]
> -----Original Message-----
> From: Andrew Lunn <[email protected]>
> Sent: Saturday, July 1, 2023 8:51 AM
> To: Quan, Evan <[email protected]>
> Cc: [email protected]; [email protected]; Deucher, Alexander
> <[email protected]>; Koenig, Christian
> <[email protected]>; Pan, Xinhui <[email protected]>;
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; Limonciello, Mario <[email protected]>;
> [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> Lazar, Lijo <[email protected]>; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected]; linux-
> [email protected]; [email protected]; dri-
> [email protected]; [email protected];
> [email protected]
> Subject: Re: [PATCH V5 2/9] driver core: add ACPI based WBRF mechanism
> introduced by AMD
>
> > + argv4 = kzalloc(sizeof(*argv4) * (2 * num_of_ranges + 2 + 1),
> GFP_KERNEL);
> > + if (!argv4)
> > + return -ENOMEM;
> > +
> > + argv4[arg_idx].package.type = ACPI_TYPE_PACKAGE;
> > + argv4[arg_idx].package.count = 2 + 2 * num_of_ranges;
> > + argv4[arg_idx++].package.elements = &argv4[1];
> > + argv4[arg_idx].integer.type = ACPI_TYPE_INTEGER;
> > + argv4[arg_idx++].integer.value = num_of_ranges;
> > + argv4[arg_idx].integer.type = ACPI_TYPE_INTEGER;
> > + argv4[arg_idx++].integer.value = action;
>
> There is a lot of magic numbers in that kzalloc. It is being used as an array,
> kcalloc() would be a good start to make it more readable.
> Can some #define's be used to explain what the other numbers mean?
Sure, will update accordingly.
>
> > + /*
> > + * Bit 0 indicates whether there's support for any functions other than
> > + * function 0.
> > + */
>
> Please make use of the BIT macro to give the different bits informative names.
Sure.
>
> > + if ((mask & 0x1) && (mask & funcs) == funcs)
> > + return true;
> > +
> > + return false;
> > +}
> > +
>
> > +int acpi_amd_wbrf_retrieve_exclusions(struct device *dev,
> > + struct wbrf_ranges_out *out) {
> > + struct acpi_device *adev = ACPI_COMPANION(dev);
> > + union acpi_object *obj;
> > +
> > + if (!adev)
> > + return -ENODEV;
> > +
> > + obj = acpi_evaluate_wbrf(adev->handle,
> > + WBRF_REVISION,
> > + WBRF_RETRIEVE);
> > + if (!obj)
> > + return -EINVAL;
> > +
> > + WARN(obj->buffer.length != sizeof(*out),
> > + "Unexpected buffer length");
> > + memcpy(out, obj->buffer.pointer, obj->buffer.length);
>
> You WARN, and then overwrite whatever i passed the end of out? Please at
> least use min(obj->buffer.length, sizeof(*out)), but better still:
>
> if (obj->buffer.length != sizeof(*out)) {
> dev_err(dev, "BIOS FUBAR, ignoring wrong sized WBRT information");
> return -EINVAL;
> }
OK. Sounds reasonable. Will update as suggested.
>
> > +#if defined(CONFIG_WBRF_GENERIC)
> > static struct exclusion_range_pool wbrf_pool;
> >
> > static int _wbrf_add_exclusion_ranges(struct wbrf_ranges_in *in) @@
> > -89,6 +92,7 @@ static int _wbrf_retrieve_exclusion_ranges(struct
> > wbrf_ranges_out *out)
> >
> > return 0;
> > }
> > +#endif
>
> I was expecting you would keep these tables, and then call into the BIOS as
> well. Having this table in debugfs seems like a useful thing to have for
> debugging the BIOS.
I'm not sure. Since these interfaces what we designed now kind of serve as a library.
When and where the debugfs should be created will be quite tricky.
>
> > +#ifdef CONFIG_WBRF_AMD_ACPI
> > +#else
> > +static inline bool
> > +acpi_amd_wbrf_supported_consumer(struct device *dev) { return false;
> > +} static inline bool acpi_amd_wbrf_supported_producer(struct device
> > +*dev) {return false; } static inline int
> > +acpi_amd_wbrf_remove_exclusion(struct device *dev,
> > + struct wbrf_ranges_in *in) { return -ENODEV; }
> static
> > +inline int acpi_amd_wbrf_add_exclusion(struct device *dev,
> > + struct wbrf_ranges_in *in) { return -ENODEV; } static
> inline
> > +int acpi_amd_wbrf_retrieve_exclusions(struct device *dev,
> > + struct wbrf_ranges_out *out) { return -
> ENODEV; }
>
> Do you actually need these stub versions?
Yes, these can be dropped. Let me update accordingly.
Evan
>
> Andrew