[PATCH v3] clocksource: acpi_pm: fix return value of __setup handler

[PATCH v3] clocksource: acpi_pm: fix return value of __setup handler

[Randy Dunlap]

__setup() handlers should return 1 to obsolete_checksetup() in
init/main.c to indicate that the boot option has been handled.
A return of 0 causes the boot option/value to be listed as an Unknown
kernel parameter and added to init's (limited) environment strings.

The __setup() handler interface isn't meant to handle negative return
values -- they are non-zero, so they mean "handled" (like a return
value of 1 does), but that's just a quirk. So return 1 from
parse_pmtmr(). Also print a warning message if kstrtouint() returns
an error.

Fixes: 6b148507d3d0 ("pmtmr: allow command line override of ioport")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
From: Igor Zhbanov <i.zhbanov@omprussia.ru>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: linux-acpi@vger.kernel.org
---
v3: also cc: linux-acpi (Rafael)
v2: correct the Fixes: tag (Dan Carpenter)

 drivers/clocksource/acpi_pm.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- linux-next-20220315.orig/drivers/clocksource/acpi_pm.c
+++ linux-next-20220315/drivers/clocksource/acpi_pm.c
@@ -229,8 +229,10 @@ static int __init parse_pmtmr(char *arg)
 	int ret;
 
 	ret = kstrtouint(arg, 16, &base);
-	if (ret)
-		return ret;
+	if (ret) {
+		pr_warn("PMTMR: invalid 'pmtmr=' value: '%s'\n", arg);
+		return 1;
+	}
 
 	pr_info("PMTMR IOPort override: 0x%04x -> 0x%04x\n", pmtmr_ioport,
 		base);

Re: [PATCH v3] clocksource: acpi_pm: fix return value of __setup handler

[Rafael J. Wysocki]

On Tue, Mar 15, 2022 at 3:41 PM Randy Dunlap <rdunlap@infradead.org> wrote:
>
> __setup() handlers should return 1 to obsolete_checksetup() in
> init/main.c to indicate that the boot option has been handled.
> A return of 0 causes the boot option/value to be listed as an Unknown
> kernel parameter and added to init's (limited) environment strings.
>
> The __setup() handler interface isn't meant to handle negative return
> values -- they are non-zero, so they mean "handled" (like a return
> value of 1 does), but that's just a quirk. So return 1 from
> parse_pmtmr(). Also print a warning message if kstrtouint() returns
> an error.
>
> Fixes: 6b148507d3d0 ("pmtmr: allow command line override of ioport")
> Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
> From: Igor Zhbanov <i.zhbanov@omprussia.ru>

What does this From tag mean?

> Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
> Cc: Dan Carpenter <dan.carpenter@oracle.com>
> Cc: John Stultz <john.stultz@linaro.org>
> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> Cc: linux-acpi@vger.kernel.org
> ---
> v3: also cc: linux-acpi (Rafael)
> v2: correct the Fixes: tag (Dan Carpenter)
>
>  drivers/clocksource/acpi_pm.c |    6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> --- linux-next-20220315.orig/drivers/clocksource/acpi_pm.c
> +++ linux-next-20220315/drivers/clocksource/acpi_pm.c
> @@ -229,8 +229,10 @@ static int __init parse_pmtmr(char *arg)
>         int ret;
>
>         ret = kstrtouint(arg, 16, &base);
> -       if (ret)
> -               return ret;
> +       if (ret) {
> +               pr_warn("PMTMR: invalid 'pmtmr=' value: '%s'\n", arg);
> +               return 1;
> +       }
>
>         pr_info("PMTMR IOPort override: 0x%04x -> 0x%04x\n", pmtmr_ioport,
>                 base);

Re: [PATCH v3] clocksource: acpi_pm: fix return value of __setup handler

[Randy Dunlap]

On 3/17/22 06:25, Rafael J. Wysocki wrote:
> On Tue, Mar 15, 2022 at 3:41 PM Randy Dunlap <rdunlap@infradead.org> wrote:
>>
>> __setup() handlers should return 1 to obsolete_checksetup() in
>> init/main.c to indicate that the boot option has been handled.
>> A return of 0 causes the boot option/value to be listed as an Unknown
>> kernel parameter and added to init's (limited) environment strings.
>>
>> The __setup() handler interface isn't meant to handle negative return
>> values -- they are non-zero, so they mean "handled" (like a return
>> value of 1 does), but that's just a quirk. So return 1 from
>> parse_pmtmr(). Also print a warning message if kstrtouint() returns
>> an error.
>>
>> Fixes: 6b148507d3d0 ("pmtmr: allow command line override of ioport")
>> Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
>> From: Igor Zhbanov <i.zhbanov@omprussia.ru>
> 
> What does this From tag mean?

Well shucks. That should be "Reported-by: Igor", like it is in all of the
other __setup handler fixing patches.
I don't know how that happened.
I'll send a v4....

thanks.

> 
>> Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
>> Cc: Dan Carpenter <dan.carpenter@oracle.com>
>> Cc: John Stultz <john.stultz@linaro.org>
>> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
>> Cc: Thomas Gleixner <tglx@linutronix.de>
>> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
>> Cc: linux-acpi@vger.kernel.org
>> ---
>> v3: also cc: linux-acpi (Rafael)
>> v2: correct the Fixes: tag (Dan Carpenter)
>>
>>  drivers/clocksource/acpi_pm.c |    6 ++++--
>>  1 file changed, 4 insertions(+), 2 deletions(-)
>>
>> --- linux-next-20220315.orig/drivers/clocksource/acpi_pm.c
>> +++ linux-next-20220315/drivers/clocksource/acpi_pm.c
>> @@ -229,8 +229,10 @@ static int __init parse_pmtmr(char *arg)
>>         int ret;
>>
>>         ret = kstrtouint(arg, 16, &base);
>> -       if (ret)
>> -               return ret;
>> +       if (ret) {
>> +               pr_warn("PMTMR: invalid 'pmtmr=' value: '%s'\n", arg);
>> +               return 1;
>> +       }
>>
>>         pr_info("PMTMR IOPort override: 0x%04x -> 0x%04x\n", pmtmr_ioport,
>>                 base);

-- 
~Randy