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From:   Stephen Kitt <steve@sk2.org>
To:     Jonathan Corbet <corbet@lwn.net>,
        Mauro Carvalho Chehab <mchehab+samsung@kernel.org>,
        linux-doc@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, Stephen Kitt <steve@sk2.org>
Subject: [PATCH 1/3] docs: sysctl/kernel: document cad_pid
Date:   Thu, 23 Apr 2020 20:36:49 +0200
Message-Id: <20200423183651.15365-1-steve@sk2.org>
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Sender: linux-kernel-owner@vger.kernel.org
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Based on the implementation in kernel/sysctl.c (the proc_do_cad_pid()
function), kernel/reboot.c, and include/linux/sched/signal.h.

Signed-off-by: Stephen Kitt <steve@sk2.org>
---
 Documentation/admin-guide/sysctl/kernel.rst | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
index 55b24eada13c..82bfd5892663 100644
--- a/Documentation/admin-guide/sysctl/kernel.rst
+++ b/Documentation/admin-guide/sysctl/kernel.rst
@@ -116,6 +116,16 @@ run. The statistics can be seen using ``bpftool``.
 = ===================================
 
 
+cad_pid
+=======
+
+This is the pid which will be signalled on reboot (notably, by
+Ctrl-Alt-Delete). Writing a value to this file which doesn't
+correspond to a running process will result in ``-ESRCH``.
+
+See also `ctrl-alt-del`_.
+
+
 cap_last_cap
 ============
 

base-commit: 7b9121040d83eb9e332f7dbc140eca17643d3586
-- 
2.20.1