Re: linux-next: build failure after merge of the paulmck tree

From: Paul E. McKenney
Date: Wed Jun 19 2024 - 13:29:12 EST


On Wed, Jun 19, 2024 at 02:49:30PM +0100, Mark Brown wrote:
> Hi all,
>
> After merging the paulmck tree, today's linux-next build (arm64
> defconfig) failed like this:
>
> /tmp/next/build/kernel/time/clocksource.c: In function '__clocksource_update_freq_scale':
> /tmp/next/build/kernel/time/clocksource.c:136:25: error: 'CONFIG_CLOCKSOURCE_WATCHDOG_MAX_SKEW_US' undeclared (first use in this function)
> 136 | #define MAX_SKEW_USEC CONFIG_CLOCKSOURCE_WATCHDOG_MAX_SKEW_US
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> /tmp/next/build/kernel/time/clocksource.c:136:25: note: in definition of macro 'MAX_SKEW_USEC'
> 136 | #define MAX_SKEW_USEC CONFIG_CLOCKSOURCE_WATCHDOG_MAX_SKEW_US
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> /tmp/next/build/kernel/time/clocksource.c:1167:50: note: in expansion of macro 'WATCHDOG_MAX_SKEW'
> 1167 | if (cs->uncertainty_margin < 2 * WATCHDOG_MAX_SKEW)
> | ^~~~~~~~~~~~~~~~~
> /tmp/next/build/kernel/time/clocksource.c:136:25: note: each undeclared identifier is reported only once for each function it appears in
> 136 | #define MAX_SKEW_USEC CONFIG_CLOCKSOURCE_WATCHDOG_MAX_SKEW_US
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> /tmp/next/build/kernel/time/clocksource.c:136:25: note: in definition of macro 'MAX_SKEW_USEC'
> 136 | #define MAX_SKEW_USEC CONFIG_CLOCKSOURCE_WATCHDOG_MAX_SKEW_US
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> /tmp/next/build/kernel/time/clocksource.c:1167:50: note: in expansion of macro 'WATCHDOG_MAX_SKEW'
> 1167 | if (cs->uncertainty_margin < 2 * WATCHDOG_MAX_SKEW)
> | ^~~~~~~~~~~~~~~~~
>
>
> Caused by commit
>
> 5800c05045dbfe ("clocksource: Take advantage of always-defined CLOCKSOURCE_WATCHDOG_MAX_SKEW_US")
>
> I have used the tree from yesterday instead.

And that commit looked so good! ;-)

Thank you for catching this. I have dropped that commit. I missed that
WATCHDOG_MAX_SKEW is used even when the clocksource watchdog is not
enabled. :-/

Thanx, Paul