Joel Savitz <jsavitz@xxxxxxxxxx> writes: > Friendly ping. This was waiting for an ack from an RCU person. Looking now, though, I see that you didn't copy any RCU people. Adding Paul and the author of the patch you reference (and appending patch below). Thanks, jon Joel Savitz <jsavitz@xxxxxxxxxx> (March 24) (kernel lwn) Subject: [PATCH] Documentation/sysctl: document max_rcu_stall_to_panic To: linux-kernel@xxxxxxxxxxxxxxx Cc: Joel Savitz <jsavitz@xxxxxxxxxx>, Jonathan Corbet <corbet@xxxxxxx>, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>, Huang Ying <ying.huang@xxxxxxxxx>, Eric Biggers <ebiggers@xxxxxxxxxx>, Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>, Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>, Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>, "Jason A. Donenfeld" <Jason@xxxxxxxxx>, Daniel Borkmann <daniel@xxxxxxxxxxxxx>, Rob Herring <robh@xxxxxxxxxx>, Wang Qing <wangqing@xxxxxxxx>, linux-doc@xxxxxxxxxxxxxxx Date: Thu, 24 Mar 2022 18:11:56 -0400 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 =========================