On 2/17/25 19:34, Ryan Roberts wrote:
> 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@xxxxxxxxxxxxxxx
> Fixes: 66b3923a1a0f ("arm64: hugetlb: add support for PTE contiguous bit")
> Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>
LGTM
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> ---
> arch/arm64/include/asm/hugetlb.h | 4 ++--
> arch/arm64/mm/hugetlbpage.c | 8 +++++---
> arch/loongarch/include/asm/hugetlb.h | 6 ++++--
> arch/mips/include/asm/hugetlb.h | 6 ++++--
> arch/parisc/include/asm/hugetlb.h | 2 +-
> arch/parisc/mm/hugetlbpage.c | 2 +-
> arch/powerpc/include/asm/hugetlb.h | 6 ++++--
> arch/riscv/include/asm/hugetlb.h | 3 ++-
> arch/riscv/mm/hugetlbpage.c | 2 +-
> arch/s390/include/asm/hugetlb.h | 12 ++++++++----
> arch/s390/mm/hugetlbpage.c | 10 ++++++++--
> arch/sparc/include/asm/hugetlb.h | 2 +-
> arch/sparc/mm/hugetlbpage.c | 2 +-
> include/asm-generic/hugetlb.h | 2 +-
> include/linux/hugetlb.h | 4 +++-
> mm/hugetlb.c | 4 ++--
> 16 files changed, 48 insertions(+), 27 deletions(-)
>
> diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
> index c6dff3e69539..03db9cb21ace 100644
> --- a/arch/arm64/include/asm/hugetlb.h
> +++ b/arch/arm64/include/asm/hugetlb.h
> @@ -42,8 +42,8 @@ extern int huge_ptep_set_access_flags(struct vm_area_struct *vma,
> unsigned long addr, pte_t *ptep,
> pte_t pte, int dirty);
> #define __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR
> -extern pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
> - unsigned long addr, pte_t *ptep);
> +extern pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
> + pte_t *ptep, unsigned long sz);
> #define __HAVE_ARCH_HUGE_PTEP_SET_WRPROTECT
> extern void huge_ptep_set_wrprotect(struct mm_struct *mm,
> unsigned long addr, pte_t *ptep);
> diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
> index 98a2a0e64e25..06db4649af91 100644
> --- a/arch/arm64/mm/hugetlbpage.c
> +++ b/arch/arm64/mm/hugetlbpage.c
> @@ -396,8 +396,8 @@ void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
> __pte_clear(mm, addr, 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, unsigned long sz)
> {
> int ncontig;
> size_t pgsize;
> @@ -549,6 +549,8 @@ bool __init arch_hugetlb_valid_size(unsigned long size)
>
> pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
> {
> + unsigned long psize = huge_page_size(hstate_vma(vma));
> +
> if (alternative_has_cap_unlikely(ARM64_WORKAROUND_2645198)) {
> /*
> * Break-before-make (BBM) is required for all user space mappings
> @@ -558,7 +560,7 @@ pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr
> if (pte_user_exec(__ptep_get(ptep)))
> return huge_ptep_clear_flush(vma, addr, ptep);
> }
> - return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
> + return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep, psize);
> }
>
> void huge_ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep,
> diff --git a/arch/loongarch/include/asm/hugetlb.h b/arch/loongarch/include/asm/hugetlb.h
> index c8e4057734d0..4dc4b3e04225 100644
> --- a/arch/loongarch/include/asm/hugetlb.h
> +++ b/arch/loongarch/include/asm/hugetlb.h
> @@ -36,7 +36,8 @@ static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
>
> #define __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR
> static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
> - unsigned long addr, pte_t *ptep)
> + unsigned long addr, pte_t *ptep,
> + unsigned long sz)
> {
> pte_t clear;
> pte_t pte = ptep_get(ptep);
> @@ -51,8 +52,9 @@ static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
> unsigned long addr, pte_t *ptep)
> {
> pte_t pte;
> + unsigned long sz = huge_page_size(hstate_vma(vma));
>
> - pte = huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
> + pte = huge_ptep_get_and_clear(vma->vm_mm, addr, ptep, sz);
> flush_tlb_page(vma, addr);
> return pte;
> }
> diff --git a/arch/mips/include/asm/hugetlb.h b/arch/mips/include/asm/hugetlb.h
> index d0a86ce83de9..fbc71ddcf0f6 100644
> --- a/arch/mips/include/asm/hugetlb.h
> +++ b/arch/mips/include/asm/hugetlb.h
> @@ -27,7 +27,8 @@ static inline int prepare_hugepage_range(struct file *file,
>
> #define __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR
> static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
> - unsigned long addr, pte_t *ptep)
> + unsigned long addr, pte_t *ptep,
> + unsigned long sz)
> {
> pte_t clear;
> pte_t pte = *ptep;
> @@ -42,13 +43,14 @@ static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
> unsigned long addr, pte_t *ptep)
> {
> pte_t pte;
> + unsigned long sz = huge_page_size(hstate_vma(vma));
>
> /*
> * clear the huge pte entry firstly, so that the other smp threads will
> * not get old pte entry after finishing flush_tlb_page and before
> * setting new huge pte entry
> */
> - pte = huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
> + pte = huge_ptep_get_and_clear(vma->vm_mm, addr, ptep, sz);
> flush_tlb_page(vma, addr);
> return pte;
> }
> diff --git a/arch/parisc/include/asm/hugetlb.h b/arch/parisc/include/asm/hugetlb.h
> index 5b3a5429f71b..21e9ace17739 100644
> --- a/arch/parisc/include/asm/hugetlb.h
> +++ b/arch/parisc/include/asm/hugetlb.h
> @@ -10,7 +10,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
>
> #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 *ptep, unsigned long sz);
>
> #define __HAVE_ARCH_HUGE_PTEP_CLEAR_FLUSH
> static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
> diff --git a/arch/parisc/mm/hugetlbpage.c b/arch/parisc/mm/hugetlbpage.c
> index e9d18cf25b79..a94fe546d434 100644
> --- a/arch/parisc/mm/hugetlbpage.c
> +++ b/arch/parisc/mm/hugetlbpage.c
> @@ -126,7 +126,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
>
>
> pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
> - pte_t *ptep)
> + pte_t *ptep, unsigned long sz)
> {
> pte_t entry;
>
> diff --git a/arch/powerpc/include/asm/hugetlb.h b/arch/powerpc/include/asm/hugetlb.h
> index dad2e7980f24..86326587e58d 100644
> --- a/arch/powerpc/include/asm/hugetlb.h
> +++ b/arch/powerpc/include/asm/hugetlb.h
> @@ -45,7 +45,8 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
>
> #define __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR
> static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
> - unsigned long addr, pte_t *ptep)
> + unsigned long addr, pte_t *ptep,
> + unsigned long sz)
> {
> return __pte(pte_update(mm, addr, ptep, ~0UL, 0, 1));
> }
> @@ -55,8 +56,9 @@ static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
> unsigned long addr, pte_t *ptep)
> {
> pte_t pte;
> + unsigned long sz = huge_page_size(hstate_vma(vma));
>
> - pte = huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
> + pte = huge_ptep_get_and_clear(vma->vm_mm, addr, ptep, sz);
> flush_hugetlb_page(vma, addr);
> return pte;
> }
> diff --git a/arch/riscv/include/asm/hugetlb.h b/arch/riscv/include/asm/hugetlb.h
> index faf3624d8057..446126497768 100644
> --- a/arch/riscv/include/asm/hugetlb.h
> +++ b/arch/riscv/include/asm/hugetlb.h
> @@ -28,7 +28,8 @@ void set_huge_pte_at(struct mm_struct *mm,
>
> #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);
> + unsigned long addr, pte_t *ptep,
> + unsigned long sz);
>
> #define __HAVE_ARCH_HUGE_PTEP_CLEAR_FLUSH
> pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
> diff --git a/arch/riscv/mm/hugetlbpage.c b/arch/riscv/mm/hugetlbpage.c
> index 42314f093922..b4a78a4b35cf 100644
> --- a/arch/riscv/mm/hugetlbpage.c
> +++ b/arch/riscv/mm/hugetlbpage.c
> @@ -293,7 +293,7 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
>
> pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
> unsigned long addr,
> - pte_t *ptep)
> + pte_t *ptep, unsigned long sz)
> {
> pte_t orig_pte = ptep_get(ptep);
> int pte_num;
> 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);
> +pte_t __huge_ptep_get_and_clear(struct mm_struct *mm,
> + unsigned long addr, pte_t *ptep);
>
> 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);
> __set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
> }
> return changed;
> @@ -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);
> +}
> +
> pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
> unsigned long addr, unsigned long sz)
> {
> diff --git a/arch/sparc/include/asm/hugetlb.h b/arch/sparc/include/asm/hugetlb.h
> index c714ca6a05aa..e7a9cdd498dc 100644
> --- a/arch/sparc/include/asm/hugetlb.h
> +++ b/arch/sparc/include/asm/hugetlb.h
> @@ -20,7 +20,7 @@ void __set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
>
> #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 *ptep, unsigned long sz);
>
> #define __HAVE_ARCH_HUGE_PTEP_CLEAR_FLUSH
> static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
> diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
> index eee601a0d2cf..80504148d8a5 100644
> --- a/arch/sparc/mm/hugetlbpage.c
> +++ b/arch/sparc/mm/hugetlbpage.c
> @@ -260,7 +260,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
> }
>
> pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
> - pte_t *ptep)
> + pte_t *ptep, unsigned long sz)
> {
> unsigned int i, nptes, orig_shift, shift;
> unsigned long size;
> diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
> index f42133dae68e..2afc95bf1655 100644
> --- a/include/asm-generic/hugetlb.h
> +++ b/include/asm-generic/hugetlb.h
> @@ -90,7 +90,7 @@ static inline void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
>
> #ifndef __HAVE_ARCH_HUGE_PTEP_GET_AND_CLEAR
> static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
> - unsigned long addr, pte_t *ptep)
> + unsigned long addr, pte_t *ptep, unsigned long sz)
> {
> return ptep_get_and_clear(mm, addr, ptep);
> }
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index ec8c0ccc8f95..bf5f7256bd28 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -1004,7 +1004,9 @@ static inline void hugetlb_count_sub(long l, struct mm_struct *mm)
> static inline pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma,
> unsigned long addr, pte_t *ptep)
> {
> - return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
> + unsigned long psize = huge_page_size(hstate_vma(vma));
> +
> + return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep, psize);
> }
> #endif
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 65068671e460..de9d49e521c1 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -5447,7 +5447,7 @@ static void move_huge_pte(struct vm_area_struct *vma, unsigned long old_addr,
> if (src_ptl != dst_ptl)
> spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
>
> - pte = huge_ptep_get_and_clear(mm, old_addr, src_pte);
> + pte = huge_ptep_get_and_clear(mm, old_addr, src_pte, sz);
>
> if (need_clear_uffd_wp && pte_marker_uffd_wp(pte))
> huge_pte_clear(mm, new_addr, dst_pte, sz);
> @@ -5622,7 +5622,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
> set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED);
> }
>
> - pte = huge_ptep_get_and_clear(mm, address, ptep);
> + pte = huge_ptep_get_and_clear(mm, address, ptep, sz);
> tlb_remove_huge_tlb_entry(h, tlb, ptep, address);
> if (huge_pte_dirty(pte))
> set_page_dirty(page);
