Re: [PATCH 0/2] console: pbl: correctly handle relocate_to_adr after pbl_set_putc

[Sascha Hauer <sha@pengutronix.de>]

On Thu, Sep 07, 2023 at 10:21:24AM +0200, Ahmad Fatoum wrote:
> pbl_set_putc may be called by a PBL entry point to store the absolute
> address of a routine to be used for printing out a character.
> 
> If barebox happens to be located outside of the initially known RAM,
> it will be relocated into it by means of relocate_to_adr(), but nothing
> will take care to update the function pointer stored by pbl_set_putc.
> 
> This will usually continue to work until barebox sets up the MMU and
> everything not known to be RAM is marked as eXecute Never. After that,
> the next PBL console print will trigger an instruction abort.
> 
> Fix this by not storing the putc function pointer, but instead an offset
> relative to _text.
> 
> This fixes the issue of barebox hanging on i.MX8M when located at an address
> greater than 4G.
> 
> 
> I thought about going further and make pbl_set_putc callable, even
> before relocation. The problem here is that runtime_address() may
> not be called on global variables defined in the same file for good
> reasons described in its documentation. So that's left as future
> exercise.
> 
> Ahmad Fatoum (2):
>   ARM: mmu64: mark barebox text section executable during early init
>   console: pbl: correctly handle relocate_to_adr after pbl_set_putc

Applied, thanks

Sascha

> 
>  arch/arm/cpu/mmu_64.c |  1 +
>  pbl/console.c         | 13 ++++++++++---
>  2 files changed, 11 insertions(+), 3 deletions(-)
> 
> -- 
> 2.39.2
> 
> 
> 

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