Re: [PATCH 06/15] powerpc: fadamp: simplify fadump_reserve_crash_area()

Michael Ellerman
2020-07-30T12:15:30Z

Mike Rapoport <rppt@kernel.org> writes:
> From: Mike Rapoport <rppt@linux.ibm.com>
>
> fadump_reserve_crash_area() reserves memory from a specified base address
> till the end of the RAM.
>
> Replace iteration through the memblock.memory with a single call to
> memblock_reserve() with appropriate that will take care of proper memory
^
parameters?
> reservation.
>
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
> arch/powerpc/kernel/fadump.c | 20 +-------------------
> 1 file changed, 1 insertion(+), 19 deletions(-)

I think this looks OK to me, but I don't have a setup to test it easily.
I've added Hari to Cc who might be able to.

But I'll give you an ack in the hope that it works :)

Acked-by: Michael Ellerman <mpe@ellerman.id.au>

> diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
> index 78ab9a6ee6ac..2446a61e3c25 100644
> --- a/arch/powerpc/kernel/fadump.c
> +++ b/arch/powerpc/kernel/fadump.c
> @@ -1658,25 +1658,7 @@ int __init fadump_reserve_mem(void)
> /* Preserve everything above the base address */
> static void __init fadump_reserve_crash_area(u64 base)
> {
> - struct memblock_region *reg;
> - u64 mstart, msize;
> -
> - for_each_memblock(memory, reg) {
> - mstart = reg->base;
> - msize = reg->size;
> -
> - if ((mstart + msize) < base)
> - continue;
> -
> - if (mstart < base) {
> - msize -= (base - mstart);
> - mstart = base;
> - }
> -
> - pr_info("Reserving %lluMB of memory at %#016llx for preserving crash data",
> - (msize >> 20), mstart);
> - memblock_reserve(mstart, msize);
> - }
> + memblock_reserve(base, memblock_end_of_DRAM() - base);
> }
>
> unsigned long __init arch_reserved_kernel_pages(void)
> --
> 2.26.2