On 30.11.20 04:29, Anshuman Khandual wrote:
> This overrides arch_get_mappable_range() on arm64 platform which will be
> used with recently added generic framework. It drops inside_linear_region()
> and subsequent check in arch_add_memory() which are no longer required.
>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: David Hildenbrand <david@xxxxxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> ---
> arch/arm64/mm/mmu.c | 14 ++++++--------
> 1 file changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> index ca692a815731..49ec8f2838f2 100644
> --- a/arch/arm64/mm/mmu.c
> +++ b/arch/arm64/mm/mmu.c
> @@ -1444,16 +1444,19 @@ static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size)
> free_empty_tables(start, end, PAGE_OFFSET, PAGE_END);
> }
>
> -static bool inside_linear_region(u64 start, u64 size)
> +struct range arch_get_mappable_range(void)
> {
> + struct range memhp_range;
> +
> /*
> * Linear mapping region is the range [PAGE_OFFSET..(PAGE_END - 1)]
> * accommodating both its ends but excluding PAGE_END. Max physical
> * range which can be mapped inside this linear mapping range, must
> * also be derived from its end points.
> */
> - return start >= __pa(_PAGE_OFFSET(vabits_actual)) &&
> - (start + size - 1) <= __pa(PAGE_END - 1);
> + memhp_range.start = __pa(_PAGE_OFFSET(vabits_actual));
> + memhp_range.end = __pa(PAGE_END - 1);
> + return memhp_range;
> }
>
> int arch_add_memory(int nid, u64 start, u64 size,
> @@ -1461,11 +1464,6 @@ int arch_add_memory(int nid, u64 start, u64 size,
> {
> int ret, flags = 0;
>
> - if (!inside_linear_region(start, size)) {
> - pr_err("[%llx %llx] is outside linear mapping region\n", start, start + size);
> - return -EINVAL;
> - }
As discussed, I think something like a VM_BUG_ON() here might makes
sense, indicating that we require the caller to validate upfront. Same
applies to the s390x variant.
Thanks!
> -
> if (rodata_full || debug_pagealloc_enabled())
> flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;
>
>
--
Thanks,
David / dhildenb
