[PATCH v4 5/5] kexec: document -s, -c and -a options.

[Dave Young]

On 03/06/18 at 02:15pm, Michal Suchanek wrote:
> Signed-off-by: Michal Suchanek <msuchanek at suse.de>
> ---
>  kexec/kexec.8 | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/kexec/kexec.8 b/kexec/kexec.8
> index e0131b4ea827..b3543db3f413 100644
> --- a/kexec/kexec.8
> +++ b/kexec/kexec.8
> @@ -144,6 +144,21 @@ Load the new kernel for use on panic.
>  Specify that the new kernel is of this
>  .I type.
>  .TP
> +.BI \-s\ (\-\-kexec-file-syscall)
> +Specify that the new KEXEC_FILE_LOAD syscall should be used exclusively.

Maybe better to be simple like below:
"Use kexec_file_load syscall to load the new kernel."


> +.TP
> +.BI \-c\ (\-\-kexec-syscall)
> +Specify that the old KEXEC_LOAD syscall should be used exclusively (the default).

similarly:
"Use kexec_load syscall to load the new kernel."

> +.TP
> +.BI \-a\ (\-\-kexec-syscall-auto)
> +Try the new simpler KEXEC_FILE_LOAD syscall first and if it is not supported
> +fall back to the old KEXEC_LOAD interface.
> +
> +There is no one single interface that always works. KEXEC_FILE_LOAD is required
> +on systems that use locked-down secure boot to verify the kernel signature.
> +KEXEC_LOAD is required for some kernel image formats and on architectures that
> +do not support KEXEC_FILE_LOAD.

It seems not good to say kexec_file_load is simpler and newer.  Also it
is not a must for Secure Boot and locked down kernel only. So it would
be better to just simplify and use the first paragraph:

"Try kexec_file_load syscall first and if it is not supported fall back
to the kexec_load syscall"

> +.TP
>  .B \-u\ (\-\-unload)
>  Unload the current
>  .B kexec
> -- 
> 2.13.6
>