Re: [PATCH] locking/mutex: Initialize mutex::magic even when LOCKDEP=n
From: Peter Zijlstra
Date: Fri Nov 28 2025 - 04:55:59 EST
On Fri, Nov 28, 2025 at 04:08:15PM +1100, Stephen Rothwell wrote:
> Hi all,
>
> On Tue, 25 Nov 2025 06:54:21 -0800 Boqun Feng <boqun.feng@xxxxxxxxx> wrote:
> >
> > When DEBUG_MUTEXES=y and LOCKDEP=n, mutex_lock() still checks on
> > ->magic, hence debug_mutex_init() should be called in
> > mutex_init_generic() as well. While we are at it, decouple LOCKDEP
> > logic from debug_mutex_init(), because in this way debug_mutex_init()
> > only needs one parameter, and we now have mutex_init_lockep() for
> > LOCKDEP=y scenarios.
> >
> > Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> > Closes: https://lore.kernel.org/lkml/20251117202214.4f710f02@xxxxxxxxxxxxxxxx/
> > Reported-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> > Closes: https://lore.kernel.org/lkml/20251121215819.GA1374726@ax162/
> > Fixes: 3572e2edc7b6 ("locking/mutex: Redo __mutex_init()")
> > Reviewed-by: Waiman Long <longman@xxxxxxxxxx>
> > Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
> > ---
> > Peter,
> >
> > Feel free to fold it into commit 3572e2edc7b6 ("locking/mutex: Redo
> > __mutex_init()"), just resend it properly so it won't fall off your
> > radar ;-)
> >
> > kernel/locking/mutex-debug.c | 10 +---------
> > kernel/locking/mutex.c | 8 +++++++-
> > kernel/locking/mutex.h | 5 ++---
> > 3 files changed, 10 insertions(+), 13 deletions(-)
>
> Any chance if this being applied? I am still seeing the boot warning.
Should be sorted now, sorry for the delay!