Re: [PATCH] tty/sysrq: Dump kernel ring buffer messages via sysrq

From: Randy Dunlap
Date: Thu Dec 21 2023 - 18:13:15 EST




On 12/21/23 08:52, Greg KH wrote:
> On Thu, Dec 21, 2023 at 07:09:53PM +0530, Sreenath Vijayan wrote:
>> When terminal is unresponsive, one cannot use dmesg to view kernel
>> ring buffer messages. Also, syslog services may be disabled,
>> to check them after a reboot, especially on embedded systems.
>> In this scenario, dump the kernel ring buffer messages via sysrq
>> by pressing sysrq+D.
>>
>> Signed-off-by: Sreenath Vijayan <sreenath.vijayan@xxxxxxxx>
>> Signed-off-by: Shimoyashiki Taichi <taichi.shimoyashiki@xxxxxxxx>
>> ---
>> Documentation/admin-guide/sysrq.rst | 2 ++
>> drivers/tty/sysrq.c | 43 ++++++++++++++++++++++++++++-
>> 2 files changed, 44 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/admin-guide/sysrq.rst b/Documentation/admin-guide/sysrq.rst
>> index 2f2e5bd440f9..464c4e138b9d 100644
>> --- a/Documentation/admin-guide/sysrq.rst
>> +++ b/Documentation/admin-guide/sysrq.rst
>> @@ -161,6 +161,8 @@ Command Function
>> will be printed to your console. (``0``, for example would make
>> it so that only emergency messages like PANICs or OOPSes would
>> make it to your console.)
>> +
>> +``D`` Dump the kernel ring buffer
>> =========== ===================================================================
>
> Nit, this doesn't line up anymore :(

Yes, that will cause a docs build warning.

Also, can you be more explicit about which ring buffer this patch
is referring to, please.


--
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