Re: [PATCH 2/2] of: of_reserved_mem: mark nomap memory instead of removing

From: Rob Herring
Date: Fri Jun 11 2021 - 13:10:53 EST


On Fri, Jun 11, 2021 at 7:13 AM Dong Aisheng <aisheng.dong@xxxxxxx> wrote:
>
> Since commit 86588296acbf ("fdt: Properly handle "no-map" field in the memory region"),
> nomap memory is changed to call memblock_mark_nomap() instead of
> memblock_remove(). But it only changed the reserved memory with fixed
> addr and size case in early_init_dt_reserve_memory_arch(), not
> including the dynamical allocation by size case in
> early_init_dt_alloc_reserved_memory_arch().
>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx

Good practice is to Cc the people involved in referenced commits.
Adding them now. This code is a minefield so I'd like other eyes on
it.

> Signed-off-by: Dong Aisheng <aisheng.dong@xxxxxxx>
> ---
> drivers/of/of_reserved_mem.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
> index 367f298a83b2..ebba88395bf8 100644
> --- a/drivers/of/of_reserved_mem.c
> +++ b/drivers/of/of_reserved_mem.c
> @@ -42,7 +42,7 @@ static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
>
> *res_base = base;
> if (nomap)
> - return memblock_remove(base, size);
> + return memblock_mark_nomap(base, size);
>
> return memblock_reserve(base, size);
> }
> @@ -276,7 +276,7 @@ void __init fdt_init_reserved_mem(void)
> pr_info("node %s compatible matching fail\n",
> rmem->name);
> if (nomap)
> - memblock_add(rmem->base, rmem->size);
> + memblock_clear_nomap(rmem->base, rmem->size);
> else
> memblock_free(rmem->base, rmem->size);
> }
> --
> 2.25.1
>