Re: [PATCH] biosmem: Narrow or widen e820 memory regions as appropriate

[Samuel Thibault]

Damien Zammit, le dim. 13 févr. 2022 08:10:29 +0000, a ecrit:
> +static void __boot
> +biosmem_map_adjust_alignment(struct biosmem_map_entry *e)
> +{
> +    if (e->type & BIOSMEM_MASK_NARROW) {
> +        e->base_addr = vm_page_round (e->base_addr);
> +        e->length = vm_page_trunc (e->length);
> +    } else {
> +        e->base_addr = vm_page_trunc (e->base_addr);
> +        e->length = vm_page_round (e->length);
> +    }
> +}

It's not so simple. Take for instance:

base_addr = 0x200
length = 0x1000

You won't be aligning the length, while you should.

It's the end of the range that you want to align, not the size.

Samuel