Re: + watchdog-fix-possible-soft-lockup-warning-at-bootup-v2.patch added to -mm tree

From: Andrew Morton
Date: Thu Jan 16 2020 - 18:53:07 EST


On Thu, 16 Jan 2020 12:55:49 +0100 Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:

> akpm@xxxxxxxxxxxxxxxxxxxx writes:
>
> > ------------------------------------------------------
> > From: Waiman Long <longman@xxxxxxxxxx>
> > Subject: watchdog: Fix possible soft lockup warning at bootup
>
> Completely empty changelog without any justification for this change.

Well, this is the v1->v2 delta. It's removing an unnecessary change
from the v1 patch. Normally that's covered in the main patch's
changelog but removing an unneeded change isn't changeloggable.

> > Link: http://lkml.kernel.org/r/20200103151032.19590-1-longman@xxxxxxxxxx
> > Signed-off-by: Waiman Long <longman@xxxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
> > Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > ---
> >
> > kernel/watchdog.c | 4 +---
> > 1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > --- a/kernel/watchdog.c~watchdog-fix-possible-soft-lockup-warning-at-bootup-v2
> > +++ a/kernel/watchdog.c
> > @@ -496,9 +496,7 @@ static void watchdog_enable(unsigned int
> > HRTIMER_MODE_REL_PINNED_HARD);
> >
> > /* Initialize timestamp */
> > - if (system_state != SYSTEM_BOOTING)
> > - __touch_watchdog();
> > -
> > + __touch_watchdog();
> > /* Enable the perf event */
> > if (watchdog_enabled & NMI_WATCHDOG_ENABLED)
> > watchdog_nmi_enable(cpu);
> > _
> >
> > Patches currently in -mm which might be from longman@xxxxxxxxxx are
> >
> > watchdog-fix-possible-soft-lockup-warning-at-bootup.patch
> > watchdog-fix-possible-soft-lockup-warning-at-bootup-v2.patch
>
> Please drop both. The initial one just papers over timer interrupt loss
> and weakens debugging. That V2 thing is just fixing up the wreckage
> introduced in the initial one.

Not really - it's removing a change which was deemed unneeded.

But sure, dropped.