[PATCH 0/4] rcu/tracing/extable: Fix stack dump when RCU is not watching

From: Steven Rostedt
Date: Fri Sep 22 2017 - 18:19:09 EST


I'm currently running this through my test suite, but wanted to get
review or acks, so that I can send this right off to Linus before rc2.
I need these to base my new work on.

Basically if a stack trace happens (say from a WARN()) when RCU is not
watching (like going to or coming from idle, or bringing down or up
a CPU), the stack trace can cause RCU issues because it requires RCU to
be watching.

We use rcu_nmi_enter() for this case, as these cases behave similar to
an NMI (can happen pretty much anywhere).


Paul E. McKenney (1):
rcu: Allow for page faults in NMI handlers

Steven Rostedt (VMware) (3):
extable: Consolidate *kernel_text_address() functions
extable: Enable RCU if it is not watching in kernel_text_address()
tracing: Remove RCU work arounds from stack tracer

----
kernel/extable.c | 45 +++++++++++++++++++++++++++++++--------------
kernel/rcu/tree.c | 10 ++++++++++
kernel/trace/trace_stack.c | 15 ---------------
3 files changed, 41 insertions(+), 29 deletions(-)