Re: [PATCH v4 03/12] powerpc/kexec_file: add helper functions for getting memory ranges

[Thiago Jung Bauermann]

Hari Bathini <hbathini@xxxxxxxxxxxxx> writes:

> In kexec case, the kernel to be loaded uses the same memory layout as
> the running kernel. So, passing on the DT of the running kernel would
> be good enough.
>
> But in case of kdump, different memory ranges are needed to manage
> loading the kdump kernel, booting into it and exporting the elfcore
> of the crashing kernel. The ranges are exclude memory ranges, usable
> memory ranges, reserved memory ranges and crash memory ranges.
>
> Exclude memory ranges specify the list of memory ranges to avoid while
> loading kdump segments. Usable memory ranges list the memory ranges
> that could be used for booting kdump kernel. Reserved memory ranges
> list the memory regions for the loading kernel's reserve map. Crash
> memory ranges list the memory ranges to be exported as the crashing
> kernel's elfcore.
>
> Add helper functions for setting up the above mentioned memory ranges.
> This helpers facilitate in understanding the subsequent changes better
> and make it easy to setup the different memory ranges listed above, as
> and when appropriate.
>
> Signed-off-by: Hari Bathini <hbathini@xxxxxxxxxxxxx>
> Tested-by: Pingfan Liu <piliu@xxxxxxxxxx>

Just one comment below, but regardless:

Reviewed-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx>

> +/**
> + * add_htab_mem_range - Adds htab range to the given memory ranges list,
> + *                      if it exists
> + * @mem_ranges:         Range list to add the memory range to.
> + *
> + * Returns 0 on success, negative errno on error.
> + */
> +int add_htab_mem_range(struct crash_mem **mem_ranges)
> +{
> +	if (!htab_address)
> +		return 0;
> +
> +	return add_mem_range(mem_ranges, __pa(htab_address), htab_size_bytes);
> +}

I believe you need to surround this function with `#ifdef
CONFIG_PPC_BOOK3S_64` and `#endif` to match what is done in
<asm/kexec_ranges.h>.

--
Thiago Jung Bauermann
IBM Linux Technology Center