Re: [PATCH] Document/kexec: Generalize crash hotplug description

[Petr Tesařík]

Hi Sourabh,

sorry for late reply, was on vacation and then catching up...

On Mon,  5 Aug 2024 10:38:29 +0530
Sourabh Jain <sourabhjain@xxxxxxxxxxxxx> wrote:

> Commit 79365026f869 ("crash: add a new kexec flag for hotplug support")
> generalizes the crash hotplug support to allow architectures to update
> multiple kexec segments on CPU/Memory hotplug and not just elfcorehdr.
> Therefore, update the relevant kernel documentation to reflect the same.
> 
> No functional change.
> 
> Cc: Petr Tesarik <petr@xxxxxxxxxxx>
> Cc: Hari Bathini <hbathini@xxxxxxxxxxxxx>
> Cc: kexec@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Cc: x86@xxxxxxxxxx
> Signed-off-by: Sourabh Jain <sourabhjain@xxxxxxxxxxxxx>
> ---
> 
> Discussion about the documentation update:
> https://lore.kernel.org/all/68d0328d-531a-4a2b-ab26-c97fd8a12e8b@xxxxxxxxxxxxx/
> 
> ---
>  .../ABI/testing/sysfs-devices-memory          |  6 ++--
>  .../ABI/testing/sysfs-devices-system-cpu      |  6 ++--
>  .../admin-guide/mm/memory-hotplug.rst         |  5 ++--
>  Documentation/core-api/cpu_hotplug.rst        | 10 ++++---
>  kernel/crash_core.c                           | 29 ++++++++++++-------
>  5 files changed, 33 insertions(+), 23 deletions(-)
> 
> diff --git a/Documentation/ABI/testing/sysfs-devices-memory b/Documentation/ABI/testing/sysfs-devices-memory
> index a95e0f17c35a..421acc8e2c6b 100644
> --- a/Documentation/ABI/testing/sysfs-devices-memory
> +++ b/Documentation/ABI/testing/sysfs-devices-memory
> @@ -115,6 +115,6 @@ What:		/sys/devices/system/memory/crash_hotplug
>  Date:		Aug 2023
>  Contact:	Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx>
>  Description:
> -		(RO) indicates whether or not the kernel directly supports
> -		modifying the crash elfcorehdr for memory hot un/plug and/or
> -		on/offline changes.
> +		(RO) indicates whether or not the kernel update of kexec
> +		segments on memory hot un/plug and/or on/offline events,
> +		avoiding the need to reload kdump kernel.

This sentence somehow lacks a verb. My suggestion:

  (RO) indicates whether or not the kernel updates relevant kexec
  segments on memory hot un/plug and/or on/offline events, avoiding the
  need to reload kdump kernel.

> diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
> index 325873385b71..f4ada1cd2f96 100644
> --- a/Documentation/ABI/testing/sysfs-devices-system-cpu
> +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
> @@ -703,9 +703,9 @@ What:		/sys/devices/system/cpu/crash_hotplug
>  Date:		Aug 2023
>  Contact:	Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx>
>  Description:
> -		(RO) indicates whether or not the kernel directly supports
> -		modifying the crash elfcorehdr for CPU hot un/plug and/or
> -		on/offline changes.
> +		(RO) indicates whether or not the kernel update of kexec
> +		segments on CPU hot un/plug and/or on/offline events,
> +		avoiding the need to reload kdump kernel.

Same as above.

Otherwise LGTM.

Petr T