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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: CA11E180005 X-Stat-Signature: ripo59q8o13mpijcfx9ho5oma5k5o5o6 X-HE-Tag: 1745991805-132635 X-HE-Meta: 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 0+ONgB9s 0xx+fmibujairDaAwiHKCE10sKjkpfWHJVsYLr9T0TKUKv0dB9ozfUxXMe33c6V8rvWdgNRsXPOVWHTa0EbY6JyC1Hv8/btuHU3G6AvUAV/Bs3VXUOMcQJsuXfro8Z4Q8jveZoK+YJunrqtn0C7ND2nEtQbSGFlN7qd3D739LvUhwi5Tfz/aiqpdReO+qfwiZILGtm78FQqrBsVpz66zhqJWj036u8+Cf/QZKRTAyf8K1snlR8OX2bhwGNQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/29/25 10:53, Dev Jain wrote: > Override the generic definition to use get_and_clear_full_ptes(), so that > we do a TLBI possibly only on the "contpte-edges" of the large PTE block, > instead of doing it for every contpte block, which happens for ptep_get_and_clear(). Could you please explain what does "contpte-edges" really signify in the context of large PTE blocks ? Also how TLBI operation only on these edges will never run into the risk of missing TLB invalidation of some other mapped areas ? > > Signed-off-by: Dev Jain > --- > arch/arm64/include/asm/pgtable.h | 5 +++++ > arch/arm64/mm/mmu.c | 12 +++++++++--- > include/linux/pgtable.h | 4 ++++ > mm/pgtable-generic.c | 16 +++++++++++----- > 4 files changed, 29 insertions(+), 8 deletions(-) > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index 2a77f11b78d5..8872ea5f0642 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -1553,6 +1553,11 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, > unsigned long addr, pte_t *ptep, > pte_t old_pte, pte_t new_pte); > > +#define modify_prot_start_ptes modify_prot_start_ptes > +extern pte_t modify_prot_start_ptes(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep, > + unsigned int nr); > + > #ifdef CONFIG_ARM64_CONTPTE > > /* > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index 8fcf59ba39db..fe60be8774f4 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -1523,7 +1523,8 @@ static int __init prevent_bootmem_remove_init(void) > early_initcall(prevent_bootmem_remove_init); > #endif > > -pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) > +pte_t modify_prot_start_ptes(struct vm_area_struct *vma, unsigned long addr, > + pte_t *ptep, unsigned int nr) > { > if (alternative_has_cap_unlikely(ARM64_WORKAROUND_2645198)) { > /* > @@ -1532,9 +1533,14 @@ pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte > * in cases where cpu is affected with errata #2645198. > */ > if (pte_user_exec(ptep_get(ptep))) > - return ptep_clear_flush(vma, addr, ptep); > + return clear_flush_ptes(vma, addr, ptep, nr); > } > - return ptep_get_and_clear(vma->vm_mm, addr, ptep); > + return get_and_clear_full_ptes(vma->vm_mm, addr, ptep, nr, 0); > +} > + > +pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) > +{ > + return modify_prot_start_ptes(vma, addr, ptep, 1); > } > > void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, > diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h > index ed287289335f..10cdb87ccecf 100644 > --- a/include/linux/pgtable.h > +++ b/include/linux/pgtable.h > @@ -828,6 +828,10 @@ extern pte_t ptep_clear_flush(struct vm_area_struct *vma, > pte_t *ptep); > #endif > > +extern pte_t clear_flush_ptes(struct vm_area_struct *vma, > + unsigned long address, > + pte_t *ptep, unsigned int nr); > + > #ifndef __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH > extern pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, > unsigned long address, > diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c > index 5a882f2b10f9..e238f88c3cac 100644 > --- a/mm/pgtable-generic.c > +++ b/mm/pgtable-generic.c > @@ -90,17 +90,23 @@ int ptep_clear_flush_young(struct vm_area_struct *vma, > } > #endif > > -#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH > -pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, > - pte_t *ptep) > +pte_t clear_flush_ptes(struct vm_area_struct *vma, unsigned long address, > + pte_t *ptep, unsigned int nr) > { > struct mm_struct *mm = (vma)->vm_mm; > pte_t pte; > - pte = ptep_get_and_clear(mm, address, ptep); > + pte = get_and_clear_full_ptes(mm, address, ptep, nr, 0); > if (pte_accessible(mm, pte)) > - flush_tlb_page(vma, address); > + flush_tlb_range(vma, address, address + nr * PAGE_SIZE); > return pte; > } > + > +#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH > +pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, > + pte_t *ptep) > +{ > + return clear_flush_ptes(vma, address, ptep, 1); > +} > #endif > > #ifdef CONFIG_TRANSPARENT_HUGEPAGE