Re: [PATCH] s390/smp: Move rcu_cpu_starting() earlier

2020-11-01 Thread Heiko Carstens
On Sat, Oct 31, 2020 at 07:38:52PM -0400, Qian Cai wrote: > > > This is avoided by moving the call to rcu_cpu_starting up near the > > > beginning of the smp_init_secondary() function. Note that the > > > raw_smp_processor_id() is required in order to avoid calling into > > > lockdep before RCU

Re: [PATCH] s390/smp: Move rcu_cpu_starting() earlier

2020-10-31 Thread Qian Cai
On Sat, 2020-10-31 at 19:37 +0100, Heiko Carstens wrote: > On Wed, Oct 28, 2020 at 02:27:42PM -0400, Qian Cai wrote: > > The call to rcu_cpu_starting() in smp_init_secondary() is not early > > enough in the CPU-hotplug onlining process, which results in lockdep > > splats as follows: > > > >

Re: [PATCH] s390/smp: Move rcu_cpu_starting() earlier

2020-10-31 Thread Heiko Carstens
On Wed, Oct 28, 2020 at 02:27:42PM -0400, Qian Cai wrote: > The call to rcu_cpu_starting() in smp_init_secondary() is not early > enough in the CPU-hotplug onlining process, which results in lockdep > splats as follows: > > WARNING: suspicious RCU usage > - >

[PATCH] s390/smp: Move rcu_cpu_starting() earlier

2020-10-28 Thread Qian Cai
The call to rcu_cpu_starting() in smp_init_secondary() is not early enough in the CPU-hotplug onlining process, which results in lockdep splats as follows: WARNING: suspicious RCU usage - kernel/locking/lockdep.c:3497 RCU-list traversed in non-reader section!!

Re: [PATCH] s390/smp: Move rcu_cpu_starting() earlier

2020-10-28 Thread Paul E. McKenney
On Wed, Oct 28, 2020 at 02:27:42PM -0400, Qian Cai wrote: > The call to rcu_cpu_starting() in smp_init_secondary() is not early > enough in the CPU-hotplug onlining process, which results in lockdep > splats as follows: > > WARNING: suspicious RCU usage > - >