[PATCH] Documentation/sysctl: document max_rcu_stall_to_panic

[Joel Savitz]

commit dfe564045c65 ("rcu: Panic after fixed number of stalls")
introduced a new systctl but no accompanying documentation.

Add a simple entry to the documentation.

Signed-off-by: Joel Savitz <jsavitz@xxxxxxxxxx>
---
 Documentation/admin-guide/sysctl/kernel.rst | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
index 803c60bf21d3..4e48139b9a34 100644
--- a/Documentation/admin-guide/sysctl/kernel.rst
+++ b/Documentation/admin-guide/sysctl/kernel.rst
@@ -781,6 +781,13 @@ is useful to define the root cause of RCU stalls using a vmcore.
 1 panic() after printing RCU stall messages.
 = ============================================================
 
+max_rcu_stall_to_panic
+======================
+
+When ``panic_on_rcu_stall`` is set to 1, this value determines the
+number of times that RCU can stall before panic() is called.
+
+When ``panic_on_rcu_stall`` is set to 0, this value is has no effect.
 
 perf_cpu_time_max_percent
 =========================
-- 
2.27.0