[PATCH 04/22] mm: use mm_is_kernel() in generic page table code

[Kevin Brodsky]

On 21/07/2026 17:07, David Hildenbrand (Arm) wrote:
> On 7/16/26 11:35, Kevin Brodsky wrote:
>> On 14/07/2026 16:03, Kevin Brodsky wrote:
>>> diff --git a/mm/memory.c b/mm/memory.c
>>> index d5e87624f692..c0244c0b0756 100644
>>> --- a/mm/memory.c
>>> +++ b/mm/memory.c
>>> @@ -3394,13 +3394,13 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd,
>>>  	spinlock_t *ptl;
>>>  
>>>  	if (create) {
>>> - mapped_pte = pte = (mm == &init_mm) ?
>>> + mapped_pte = pte = mm_is_kernel(mm) ?
>>>  			pte_alloc_kernel_track(pmd, addr, mask) :
>>>  			pte_alloc_map_lock(mm, pmd, addr, &ptl);
>> As noted by Sashiko, this is a little problematic because if
>> apply_to_page_range() is called on efi_mm, then we will end up with
>> __pte_alloc_kernel() taking the init_mm lock, since that's hardcoded.
>>
>> That probably means we should pass the mm to __pte_alloc_kernel().
> Agreed.
>
> I guess we have to audit all existing init_mm usage?

Indeed, I looked through comparisons with &init_mm but really all
references to init_mm should be checked. Will do for v2.

- Kevin