Commit-ID: 8146c4e2e2c1972216afece5c50e072e86120e42 Gitweb: http://git.kernel.org/tip/8146c4e2e2c1972216afece5c50e072e86120e42 Author: Paul E. McKenney <paul.mckenney@xxxxxxxxxx> AuthorDate: Tue, 10 Jan 2012 14:23:29 -0800 Committer: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> CommitDate: Tue, 21 Feb 2012 09:03:37 -0800 rcu: Check for callback invocation from offline CPUs Because quiescent states are now reported from offline CPUs in CPU_DYING state, there is some possibility that such a CPU might note the end of a grace period and attempt to start invoking callbacks. This would be a very bad thing, and is supposed to be prevented by the fact that the CPU_DYING CPU gets rid of all its callbacks before reporting the quiescent state. However, there is other CPU-offline code in the kernel, and it is quite possible that someone will invoke RCU core processing from that code. Therefore, this commit adds a warning for this case. Signed-off-by: Paul E. McKenney <paul.mckenney@xxxxxxxxxx> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> --- kernel/rcutree.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 575f91d..ac3a810 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -1373,6 +1373,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) * races with call_rcu() from interrupt handlers. */ local_irq_save(flags); + WARN_ON_ONCE(cpu_is_offline(smp_processor_id())); bl = rdp->blimit; trace_rcu_batch_start(rsp->name, rdp->qlen_lazy, rdp->qlen, bl); list = rdp->nxtlist; -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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