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> } > > +#ifdef CONFIG_LOCKDEP > +static void ptp_vclock_set_subclass(struct ptp_clock *ptp) > +{ > + lockdep_set_subclass(&ptp->n_vclocks_mux, PTP_LOCK_VIRTUAL); > + lockdep_set_subclass(&ptp->clock.rwsem, PTP_LOCK_VIRTUAL); > + lockdep_set_subclass(&ptp->tsevqs_lock, PTP_LOCK_VIRTUAL); > + lockdep_set_subclass(&ptp->pincfg_mux, PTP_LOCK_VIRTUAL); Every other lock except &ptp->clock.rwsem is unrelated, and I wouldn't touch what is unrelated as part of a bug fix. That, plus I believe this breaks the data encapsulation of struct posix_clock. At least CC the "POSIX CLOCKS and TIMERS" maintainers in v4, so that they're aware of your intentions. > +} > +#else > +static void ptp_vclock_set_subclass(struct ptp_clock *ptp) > +{ > +} > +#endif > + lockdep_set_subclass() has shim definitions for CONFIG_LOCKDEP=n, you don't need the #ifdef.