Messages in this thread Patch in this message | | | Date | Tue, 27 Jun 2017 17:44:46 -0700 | From | "Paul E. McKenney" <> | Subject | Re: [BUG] ftrace: WARNING: suspicious RCU usage |
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On Tue, Jun 27, 2017 at 06:57:43PM -0400, Steven Rostedt wrote: > On Wed, 28 Jun 2017 07:52:22 +0900 > Masami Hiramatsu <mhiramat@kernel.org> wrote: > > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > > index e354e47..442b409 100644 > > --- a/kernel/rcu/tree.c > > +++ b/kernel/rcu/tree.c > > @@ -973,8 +973,10 @@ static void rcu_eqs_exit(bool user) > > if (oldval & DYNTICK_TASK_NEST_MASK) { > > rdtp->dynticks_nesting += DYNTICK_TASK_NEST_VALUE; > > } else { > > + __this_cpu_inc(disable_rcu_irq_enter); > > rdtp->dynticks_nesting = DYNTICK_TASK_EXIT_IDLE; > > rcu_eqs_exit_common(oldval, user); > > + __this_cpu_dec(disable_rcu_irq_enter); > > } > > } > > > > Looks like a good fix to me. Paul want to take this one? > > Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Why not?
How urgent is this, as in what release do you need it in? (Default at this point being v4.14, but non-default available upon request.)
Thanx, Paul
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commit 2165b0a9bb37f0560f261986783e7c02bb37c353 Author: Masami Hiramatsu <mhiramat@kernel.org> Date: Tue Jun 27 17:41:25 2017 -0700
rcu/tracing: Set disable_rcu_irq_enter on rcu_eqs_exit() Set disable_rcu_irq_enter on not only rcu_eqs_enter_common() but also rcu_eqs_exit(), since rcu_eqs_exit() suffers from the same issue as was fixed for rcu_eqs_enter_common() by commit 03ecd3f48e57 ("rcu/tracing: Add rcu_disabled to denote when rcu_irq_enter() will not work"). Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index ca3076b073e4..2a6b610ef54f 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -952,8 +952,10 @@ static void rcu_eqs_exit(bool user) if (oldval & DYNTICK_TASK_NEST_MASK) { rdtp->dynticks_nesting += DYNTICK_TASK_NEST_VALUE; } else { + __this_cpu_inc(disable_rcu_irq_enter); rdtp->dynticks_nesting = DYNTICK_TASK_EXIT_IDLE; rcu_eqs_exit_common(oldval, user); + __this_cpu_dec(disable_rcu_irq_enter); } }
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