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From:   Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
To:     corbet@lwn.net, mcgrof@kernel.org, keescook@chromium.org,
        yzaikin@google.com, linux-fsdevel@vger.kernel.org,
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Subject: [RFC 0/1] Add sysctl entry for controlling crash_kexec_post_notifiers
Date:   Fri,  1 Apr 2022 16:22:59 -0400
Message-Id: <20220401202300.12660-1-alejandro.j.jimenez@oracle.com>
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I noticed that in contrast to other kernel core parameters (e.g. kernel.panic,
kernel.panic_on_warn, kernel.panic_print) crash_kexec_post_notifiers is not
available as a sysctl tunable. I am aware that because it is a kernel core
parameter, there is already an entry under:

  /sys/module/kernel/parameters/crash_kexec_post_notifiers

and that allows us to read/modify it at runtime. However, I thought it should
also be available via sysctl, since users that want to read/set this value at
runtime might look there first.

I believe there is an ongoing effort to clean up kernel/sysctl.c, but it wasn't
clear to me if this entry (and perhaps the other panic related entries too)
should be placed on kernel/panic.c. I wanted to verify first that this change
would be welcomed before doing additional refactoring work.

I'd appreciate any comments or suggestions.

Thank you,
Alejandro

Alejandro Jimenez (1):
  kernel/sysctl: Add sysctl entry for crash_kexec_post_notifiers

 Documentation/admin-guide/sysctl/kernel.rst | 8 ++++++++
 include/uapi/linux/sysctl.h                 | 1 +
 kernel/sysctl.c                             | 7 +++++++
 3 files changed, 16 insertions(+)

-- 
2.34.1