Re: [PATCH v3] powerpc/fadump: when fadump is supported register the fadump sysfs files.

[Hari Bathini <hbathini@linux.ibm.com>]

On 07/11/19 10:17 PM, Michal Suchanek wrote:
> Currently it is not possible to distinguish the case when fadump is
> supported by firmware and disabled in kernel and completely unsupported
> using the kernel sysfs interface. User can investigate the devicetree
> but it is more reasonable to provide sysfs files in case we get some
> fadumpv2 in the future.
> 
> With this patch sysfs files are available whenever fadump is supported
> by firmware.
> 
> There is duplicate message about lack of support by firmware in
> fadump_reserve_mem and setup_fadump. Remove the duplicate message in
> setup_fadump.

Thanks for doing this, Michal.
Exporting the node will be helpful in finding if FADump is supported,
given FADump is now supported on two different platforms...

Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>

> 
> Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> ---
> v2: move the sysfs initialization earlier to avoid condition nesting
> v3: remove duplicate message
> ---
>  arch/powerpc/kernel/fadump.c | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
> index ed59855430b9..ff0114aeba9b 100644
> --- a/arch/powerpc/kernel/fadump.c
> +++ b/arch/powerpc/kernel/fadump.c
> @@ -1466,16 +1466,15 @@ static void fadump_init_files(void)
>   */
>  int __init setup_fadump(void)
>  {
> -	if (!fw_dump.fadump_enabled)
> -		return 0;
> -
> -	if (!fw_dump.fadump_supported) {
> -		printk(KERN_ERR "Firmware-assisted dump is not supported on"
> -			" this hardware\n");
> +	if (!fw_dump.fadump_supported)
>  		return 0;
> -	}
>  
> +	fadump_init_files();
>  	fadump_show_config();
> +
> +	if (!fw_dump.fadump_enabled)
> +		return 1;
> +
>  	/*
>  	 * If dump data is available then see if it is valid and prepare for
>  	 * saving it to the disk.
> @@ -1492,8 +1491,6 @@ int __init setup_fadump(void)
>  	else if (fw_dump.reserve_dump_area_size)
>  		fw_dump.ops->fadump_init_mem_struct(&fw_dump);
>  
> -	fadump_init_files();
> -
>  	return 1;
>  }
>  subsys_initcall(setup_fadump);
> 

-- 
- Hari