[PATCH v1 2/3] kernel/resource: make walk_mem_res() find all busy IORESOURCE_MEM resources

[Dan Williams]

On Mon, Mar 22, 2021 at 9:02 AM David Hildenbrand <david at redhat.com> wrote:
>
> It used to be true that we can have system RAM only on the first level
> in the resourc tree. However, this is no longer holds for driver-managed
> system RAM (i.e., dax/kmem and virtio-mem).
>
> The function walk_mem_res() only consideres the first level and is
> used in arch/x86/mm/ioremap.c:__ioremap_check_mem() only. We currently
> fail to identify System RAM added by dax/kmem and virtio-mem as
> "IORES_MAP_SYSTEM_RAM", for example, allowing for remapping of such
> "normal RAM" in __ioremap_caller().
>
> Let's find all busy IORESOURCE_MEM resources, making the function
> behave similar to walk_system_ram_res().

Looks good,

Reviewed-by: Dan Williams <dan.j.williams at intel.com>