On Mon, Feb 17, 2025 at 02:04:14PM +0000, Ryan Roberts wrote:
Hi Ryan,
In order to fix a bug, arm64 needs to be told the size of the huge page for which the huge_pte is being set in huge_ptep_get_and_clear(). Provide for this by adding an `unsigned long sz` parameter to the function. This follows the same pattern as huge_pte_clear() and set_huge_pte_at().
This commit makes the required interface modifications to the core mm as well as all arches that implement this function (arm64, loongarch, mips, parisc, powerpc, riscv, s390, sparc). The actual arm64 bug will be fixed in a separate commit.
Cc: stable@vger.kernel.org Fixes: 66b3923a1a0f ("arm64: hugetlb: add support for PTE contiguous bit") Signed-off-by: Ryan Roberts ryan.roberts@arm.com
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diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h index 7c52acaf9f82..420c74306779 100644 --- a/arch/s390/include/asm/hugetlb.h +++ b/arch/s390/include/asm/hugetlb.h @@ -26,7 +26,11 @@ void __set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t huge_ptep_get(struct mm_struct *mm, unsigned long addr, pte_t *ptep); #define __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR -pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep); +pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep,unsigned long sz);
Please, format parameters similarily to set_huge_pte_at() few lines above.
+pte_t __huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep);
The formatting is broken, but please see below.
static inline void arch_clear_hugetlb_flags(struct folio *folio) { @@ -48,7 +52,7 @@ static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr, static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) {
- return huge_ptep_get_and_clear(vma->vm_mm, address, ptep);
- return __huge_ptep_get_and_clear(vma->vm_mm, address, ptep);
} #define __HAVE_ARCH_HUGE_PTEP_SET_ACCESS_FLAGS @@ -59,7 +63,7 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma, int changed = !pte_same(huge_ptep_get(vma->vm_mm, addr, ptep), pte); if (changed) {
huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
__huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);@@ -69,7 +73,7 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma, static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) {
- pte_t pte = huge_ptep_get_and_clear(mm, addr, ptep);
- pte_t pte = __huge_ptep_get_and_clear(mm, addr, ptep);
__set_huge_pte_at(mm, addr, ptep, pte_wrprotect(pte)); } diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c index d9ce199953de..52ee8e854195 100644 --- a/arch/s390/mm/hugetlbpage.c +++ b/arch/s390/mm/hugetlbpage.c @@ -188,8 +188,8 @@ pte_t huge_ptep_get(struct mm_struct *mm, unsigned long addr, pte_t *ptep) return __rste_to_pte(pte_val(*ptep)); } -pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)+pte_t __huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep){ pte_t pte = huge_ptep_get(mm, addr, ptep); pmd_t *pmdp = (pmd_t *) ptep; @@ -202,6 +202,12 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, return pte; } +pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep, unsigned long sz)+{
- return __huge_ptep_get_and_clear(mm, addr, ptep);
+}
Is there a reason why this is not a header inline, as other callers of __huge_ptep_get_and_clear()?
pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned long sz) {
...
Thanks!