Re: [PATCH v2 2/4] arm64: hugetlb: Fix huge_ptep_get_and_clear() for non-present ptes

On Mon, Feb 17, 2025 at 02:04:15PM +0000, Ryan Roberts wrote:

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 06db4649af91..614b2feddba2 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -163,24 +163,23 @@ static pte_t get_clear_contig(struct mm_struct *mm, unsigned long pgsize, unsigned long ncontig) {

• pte_t orig_pte = __ptep_get(ptep);
• unsigned long i;
• for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) {

• pte_t pte = __ptep_get_and_clear(mm, addr, ptep);
  

• /*
  

•  * If HW_AFDBM is enabled, then the HW could turn on
  

•  * the dirty or accessed bit for any page in the set,
  

•  * so check them all.
  

•  */
  

• if (pte_dirty(pte))
  

• 	orig_pte = pte_mkdirty(orig_pte);
  

• if (pte_young(pte))
  

• 	orig_pte = pte_mkyoung(orig_pte);
  

• pte_t pte, tmp_pte;
• bool present;
• pte = __ptep_get_and_clear(mm, addr, ptep);
• present = pte_present(pte);
• while (--ncontig) {

A 'for' loop may be more consistent with the rest of the file but I really don't mind the 'while' loop.

Reviewed-by: Catalin Marinas catalin.marinas@arm.com