Subject: Re: [PATCH 0/2] of: remove reserved regions count restriction

From: Mike Rapoport <[email-masked]>
Date: Sun, 21 Nov 2021 08:43:47 +0200

On Fri, Nov 19, 2021 at 03:58:17PM +0800, Calvin Zhang wrote:
> The count of reserved regions in /reserved-memory was limited because
> the struct reserved_mem array was defined statically. This series sorts
> out reserved memory code and allocates that array from early allocator.
> 
> Note: reserved region with fixed location must be reserved before any
> memory allocation. While struct reserved_mem array should be allocated
> after allocator is activated. We make early_init_fdt_scan_reserved_mem()
> do reservation only and add another call to initialize reserved memory.
> So arch code have to change for it.

I think much simpler would be to use the same constant for sizing
memblock.reserved and reserved_mem arrays.

If there is too much reserved regions in the device tree, reserving them in
memblock will fail anyway because memblock also starts with static array
for memblock.reserved, so doing one pass with memblock_reserve() and
another to set up reserved_mem wouldn't help anyway.

> I'm only familiar with arm and arm64 architectures. Approvals from arch
> maintainers are required. Thank you all.
> 
> Calvin Zhang (2):
>   of: Sort reserved_mem related code
>   of: reserved_mem: Remove reserved regions count restriction
> 
>  arch/arc/mm/init.c                 |   3 +
>  arch/arm/kernel/setup.c            |   2 +
>  arch/arm64/kernel/setup.c          |   3 +
>  arch/csky/kernel/setup.c           |   3 +
>  arch/h8300/kernel/setup.c          |   2 +
>  arch/mips/kernel/setup.c           |   3 +
>  arch/nds32/kernel/setup.c          |   3 +
>  arch/nios2/kernel/setup.c          |   2 +
>  arch/openrisc/kernel/setup.c       |   3 +
>  arch/powerpc/kernel/setup-common.c |   3 +
>  arch/riscv/kernel/setup.c          |   2 +
>  arch/sh/kernel/setup.c             |   3 +
>  arch/xtensa/kernel/setup.c         |   2 +
>  drivers/of/fdt.c                   | 107 +---------------
>  drivers/of/of_private.h            |  12 +-
>  drivers/of/of_reserved_mem.c       | 189 ++++++++++++++++++++++++-----
>  include/linux/of_reserved_mem.h    |   4 +
>  17 files changed, 207 insertions(+), 139 deletions(-)
> 
> -- 
> 2.30.2
> 

-- 
Sincerely yours,
Mike.