[PATCH 00/12] ARM: use adr_l/ldr_l macros for PC-relative references

[Mike Rapoport]

(added Mike K.)

On Wed, Sep 16, 2020 at 05:16:32PM -0700, Nick Desaulniers wrote:
> On Wed, Sep 16, 2020 at 2:25 PM Nick Desaulniers
> <ndesaulniers at google.com> wrote:

...
 
> Maybe this is: https://lore.kernel.org/linux-next/20200916140437.GL2142832@kernel.org/
> ? That looks arm64 specific though.  Maybe 32b ARM needs the same or a
> similar fix?  Oh man, this boots, total shot in the dark:

The CMA change is the problem IMO and it's now removed from -mm and
-next trees. 

> diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
> index 45f9d5ec2360..7118b98c1f5f 100644
> --- a/arch/arm/mm/init.c
> +++ b/arch/arm/mm/init.c
> @@ -226,9 +226,6 @@ void __init arm_memblock_init(const struct
> machine_desc *mdesc)
>         early_init_fdt_reserve_self();
>         early_init_fdt_scan_reserved_mem();
> 
> -       /* reserve memory for DMA contiguous allocations */
> -       dma_contiguous_reserve(arm_dma_limit);
> -
>         arm_memblock_steal_permitted = false;
>         memblock_dump_all();
>  }
> @@ -248,6 +245,9 @@ void __init bootmem_init(void)
>          */
>         sparse_init();
> 
> +       /* reserve memory for DMA contiguous allocations */
> +       dma_contiguous_reserve(arm_dma_limit);
> +

This might be too late for ARM because in paging_init() it calls
dma_contiguous_remap() which presumes that the CMA area is already
reserved.

dma_contiguous_remap() might be NOP, so your fix will boot until it
fails eventually :) 

>         /*
>          * Now free the memory - free_area_init needs
>          * the sparse mem_map arrays initialized by sparse_init()

-- 
Sincerely yours,
Mike.