On 12/2/20 2:56 PM, David Hildenbrand wrote: > 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. Sure, will do. > > Thanks! >