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Date:   Sat, 16 Sep 2023 14:57:30 +0200
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Subject: Re: [PATCH v2] x86/platform/uv: Rework NMI "action" modparam handling
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To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     Steve Wahl <steve.wahl@hpe.com>,
        Justin Ernst <justin.ernst@hpe.com>,
        Kyle Meyer <kyle.meyer@hpe.com>,
        Dimitri Sivanich <dimitri.sivanich@hpe.com>,
        Russ Anderson <russ.anderson@hpe.com>,
        Darren Hart <dvhart@infradead.org>,
        Andy Shevchenko <andy@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H . Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, Justin Stitt <justinstitt@google.com>
References: <20230913180111.85397-1-hdegoede@redhat.com>
 <CAHp75VdTO2=2a_7tqH72tji=UWhmjNpaO+tE8sq+ufdjY6+Low@mail.gmail.com>
From:   Hans de Goede <hdegoede@redhat.com>
In-Reply-To: <CAHp75VdTO2=2a_7tqH72tji=UWhmjNpaO+tE8sq+ufdjY6+Low@mail.gmail.com>
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Hi,

On 9/14/23 10:42, Andy Shevchenko wrote:
> On Wed, Sep 13, 2023 at 9:01 PM Hans de Goede <hdegoede@redhat.com> wrote:
>>
>> Rework NMI "action" modparam handling:
>>
>> 1. Replace the uv_nmi_action string with an enum; and
>> 2. Use sysfs_match_string() for string parsing in param_set_action()
> 
> ...
> 
> Don't you need to include string.h?

Yes (pre-existing problem really, but still). Will fix for v3.

> 
> ...
> 
>> +enum action_t {
>> +       nmi_act_kdump,
>> +       nmi_act_dump,
>> +       nmi_act_ips,
>> +       nmi_act_kdb,
>> +       nmi_act_kgdb,
>> +       nmi_act_health,
>>  };
> 
>> +
>> +static_assert(ARRAY_SIZE(actions) == ARRAY_SIZE(actions_desc));
> 
> I believe with enum in place you don't need this, just add a terminator to it
> 
> enum action_t {
>    ...
>    nmi_act_max
> };
> 
> and use as an array size both arrays.
> 
> ...
> 
>> -       int i;
>> -       int n = ARRAY_SIZE(valid_acts);
> 
>> +       int i, n = ARRAY_SIZE(actions);
> 
> Since you are changing them, why not make them unsigned?

i is used to store the result of sysfs_match_string() which
returns a negative errno.

> 
> ...
> 
>> -       pr_err("UV: Invalid NMI action:%s, valid actions are:\n", arg);
>> +       pr_err("UV: Invalid NMI action:%s, valid actions are:\n", val);
> 
> As mentioned previously the val may or may not have a new line in it.
> I dunno about comma removal, but a new line presence can be easily checked.
> 
> Either way it's not so critical, hence removing comma. or replacing it
> by '-' (dash) may be enough.

I'll fix this for v3 by not printing the wrong val at all as suggested
by Steve Wahl.

Regards,

Hans