Re: [PATCH master] ARM: mmu: increase early page table size to 256K for now

[Sascha Hauer]

On Fri, 22 Aug 2025 16:01:11 +0200, Ahmad Fatoum wrote:
> With recent changes for W^X, the size of our early page tables have grown
> in some cases, so they no longer fit into the 64K we reserve for them.
> 
> This has been observed in at least two ARM64 platforms:
> 
>   - i.MX8M with OP-TEE at start of RAM (on master)
>   - Raspberry Pi Zero 2 without OP-TEE (on next)
> 
> [...]

Applied, thanks!

[1/1] ARM: mmu: increase early page table size to 256K for now
  https://git.pengutronix.de/cgit/barebox/commit/?id=ea4adae23e66 (link may 
not be stable)

Best regards,
-- 
Sascha Hauer 

Re: [PATCH master] ARM: mmu: increase early page table size to 256K for now

[Marco Felsch]

Hi Ahmad,

On 25-08-22, Ahmad Fatoum wrote:
> With recent changes for W^X, the size of our early page tables have grown
> in some cases, so they no longer fit into the 64K we reserve for them.
> 
> This has been observed in at least two ARM64 platforms:
> 
>   - i.MX8M with OP-TEE at start of RAM (on master)
>   - Raspberry Pi Zero 2 without OP-TEE (on next)
> 
> It's very likely we are overly wasteful of space, but until that's fixed
> properly, increase the size reserved for our early page tables.

shall we add a TODO within the code?

> Signed-off-by: Ahmad Fatoum 

Reviewed-by: Marco Felsch 

Regards,
  Marco


> ---
>  arch/arm/include/asm/barebox-arm.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm/include/asm/barebox-arm.h 
> b/arch/arm/include/asm/barebox-arm.h
> index da6f5d528338..11be8b85837e 100644
> --- a/arch/arm/include/asm/barebox-arm.h
> +++ b/arch/arm/include/asm/barebox-arm.h
> @@ -26,7 +26,7 @@
>  #include 
>  #include 
>  
> -#define ARM_EARLY_PAGETABLE_SIZE SZ_64K
> +#define ARM_EARLY_PAGETABLE_SIZE SZ_256K
>  
>  #define handoff_add_arm_machine(machine) \
>   do {\
> -- 
> 2.39.5
> 
>