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McKenney wrote: > On Tue, Oct 20, 2026 at 03:01:27PM -0700, Paul E. McKenney wrote: > > On Tue, Oct 20, 2026 at 04:06:49PM +0100, Bradley Morgan wrote: > > > On 20 October 2026 10:49:07 BST, Zqiang wrote: > > > >Running the trivial-preempt flavor triggers a lockdep "suspicious RCU > > > >usage" warning from rcu_torture_one_read_start(): > > > > > > > >WARNING: suspicious RCU usage > > > >kernel/rcu/rcutorture.c:2581 suspicious rcu_dereference_check() usage! > > > >... > > > >lockdep_rcu_suspicious > > > >rcu_torture_one_read_start > > > >rcu_torture_one_read > > > >rcu_torture_reader > > > > > > > >The trivial-preempt flavor .readlock_held is set to > > > >torture_readlock_not_held(), > > > >which check RCU-bh/RCU-sched critical sections. however, it's read lock > > > >just increments current->rcu_trivial_preempt_nesting, it's not also RCU > > > >read critical sections. the rcu_dereference_check() condition is therefore > > > >false, and lockdep report warnings. this commit therefore drop > > > >.readlock_held > > > >callback to avoid this lockdep warnings. > > > > > > > >Fixes: c6f4e552e1ea ("rcutorture: Add a textbook-style trivial preemptible RCU") > > > > > > Looks ok to me. > > > > > > Reviewed-by: Bradley Morgan > > > > > > >Signed-off-by: Zqiang > > > > And it works here, thank you both. I have queued this, and thank you > > Zqiang for thinking to test trivial-preempt with lockdep enabled! > > Wait, Joel is doing the next merge window, not me! > > Joel, please make that be: > > Reviewed-by: Paul E. McKenney > Tested-by: Paul E. McKenney > > I will drop it from my tree, apologies for my confusion! Applied for 7.5 for further testing, thanks! thanks, Joel Fernandes