diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h index 293f880865e8d..c6dff3e69539b 100644 --- a/arch/arm64/include/asm/hugetlb.h +++ b/arch/arm64/include/asm/hugetlb.h @@ -11,6 +11,7 @@ #define __ASM_HUGETLB_H #include +#include #include #ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION @@ -21,6 +22,13 @@ extern bool arch_hugetlb_migration_supported(struct hstate *h); static inline void arch_clear_hugetlb_flags(struct folio *folio) { clear_bit(PG_dcache_clean, &folio->flags); + +#ifdef CONFIG_ARM64_MTE + if (system_supports_mte()) { + clear_bit(PG_mte_tagged, &folio->flags); + clear_bit(PG_mte_lock, &folio->flags); + } +#endif } #define arch_clear_hugetlb_flags arch_clear_hugetlb_flags diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h index 9e39217b4afbb..65bc2b07f6663 100644 --- a/arch/arm64/include/asm/mman.h +++ b/arch/arm64/include/asm/mman.h @@ -38,7 +38,8 @@ static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags) * backed by tags-capable memory. The vm_flags may be overridden by a * filesystem supporting MTE (RAM-based). */ - if (system_supports_mte() && (flags & MAP_ANONYMOUS)) + if (system_supports_mte() && + (flags & (MAP_ANONYMOUS | MAP_HUGETLB))) return VM_MTE_ALLOWED; return 0; diff --git a/arch/arm64/include/asm/mte.h b/arch/arm64/include/asm/mte.h index 0f84518632b4a..6567df8ec8ca8 100644 --- a/arch/arm64/include/asm/mte.h +++ b/arch/arm64/include/asm/mte.h @@ -41,6 +41,8 @@ void mte_free_tag_storage(char *storage); static inline void set_page_mte_tagged(struct page *page) { + VM_WARN_ON_ONCE(folio_test_hugetlb(page_folio(page))); + /* * Ensure that the tags written prior to this function are visible * before the page flags update. @@ -53,6 +55,8 @@ static inline bool page_mte_tagged(struct page *page) { bool ret = test_bit(PG_mte_tagged, &page->flags); + VM_WARN_ON_ONCE(folio_test_hugetlb(page_folio(page))); + /* * If the page is tagged, ensure ordering with a likely subsequent * read of the tags. @@ -76,6 +80,8 @@ static inline bool page_mte_tagged(struct page *page) */ static inline bool try_page_mte_tagging(struct page *page) { + VM_WARN_ON_ONCE(folio_test_hugetlb(page_folio(page))); + if (!test_and_set_bit(PG_mte_lock, &page->flags)) return true; @@ -157,6 +163,67 @@ static inline int mte_ptrace_copy_tags(struct task_struct *child, #endif /* CONFIG_ARM64_MTE */ +#if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_ARM64_MTE) +static inline void folio_set_hugetlb_mte_tagged(struct folio *folio) +{ + VM_WARN_ON_ONCE(!folio_test_hugetlb(folio)); + + /* + * Ensure that the tags written prior to this function are visible + * before the folio flags update. + */ + smp_wmb(); + set_bit(PG_mte_tagged, &folio->flags); + +} + +static inline bool folio_test_hugetlb_mte_tagged(struct folio *folio) +{ + bool ret = test_bit(PG_mte_tagged, &folio->flags); + + VM_WARN_ON_ONCE(!folio_test_hugetlb(folio)); + + /* + * If the folio is tagged, ensure ordering with a likely subsequent + * read of the tags. + */ + if (ret) + smp_rmb(); + return ret; +} + +static inline bool folio_try_hugetlb_mte_tagging(struct folio *folio) +{ + VM_WARN_ON_ONCE(!folio_test_hugetlb(folio)); + + if (!test_and_set_bit(PG_mte_lock, &folio->flags)) + return true; + + /* + * The tags are either being initialised or may have been initialised + * already. Check if the PG_mte_tagged flag has been set or wait + * otherwise. + */ + smp_cond_load_acquire(&folio->flags, VAL & (1UL << PG_mte_tagged)); + + return false; +} +#else +static inline void folio_set_hugetlb_mte_tagged(struct folio *folio) +{ +} + +static inline bool folio_test_hugetlb_mte_tagged(struct folio *folio) +{ + return false; +} + +static inline bool folio_try_hugetlb_mte_tagging(struct folio *folio) +{ + return false; +} +#endif + static inline void mte_disable_tco_entry(struct task_struct *task) { if (!system_supports_mte()) diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c index 7b11d84f533c9..18749e9a6c2da 100644 --- a/arch/arm64/kernel/hibernate.c +++ b/arch/arm64/kernel/hibernate.c @@ -266,9 +266,15 @@ static int swsusp_mte_save_tags(void) max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { struct page *page = pfn_to_online_page(pfn); + struct folio *folio; if (!page) continue; + folio = page_folio(page); + + if (folio_test_hugetlb(folio) && + !folio_test_hugetlb_mte_tagged(folio)) + continue; if (!page_mte_tagged(page)) continue; diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c index 6174671be7c18..2fbfd27ff5f29 100644 --- a/arch/arm64/kernel/mte.c +++ b/arch/arm64/kernel/mte.c @@ -38,7 +38,24 @@ EXPORT_SYMBOL_GPL(mte_async_or_asymm_mode); void mte_sync_tags(pte_t pte, unsigned int nr_pages) { struct page *page = pte_page(pte); - unsigned int i; + struct folio *folio = page_folio(page); + unsigned long i; + + if (folio_test_hugetlb(folio)) { + unsigned long nr = folio_nr_pages(folio); + + /* Hugetlb MTE flags are set for head page only */ + if (folio_try_hugetlb_mte_tagging(folio)) { + for (i = 0; i < nr; i++, page++) + mte_clear_page_tags(page_address(page)); + folio_set_hugetlb_mte_tagged(folio); + } + + /* ensure the tags are visible before the PTE is set */ + smp_wmb(); + + return; + } /* if PG_mte_tagged is set, tags have already been initialised */ for (i = 0; i < nr_pages; i++, page++) { @@ -410,6 +427,7 @@ static int __access_remote_tags(struct mm_struct *mm, unsigned long addr, void *maddr; struct page *page = get_user_page_vma_remote(mm, addr, gup_flags, &vma); + struct folio *folio; if (IS_ERR(page)) { err = PTR_ERR(page); @@ -428,7 +446,12 @@ static int __access_remote_tags(struct mm_struct *mm, unsigned long addr, put_page(page); break; } - WARN_ON_ONCE(!page_mte_tagged(page)); + + folio = page_folio(page); + if (folio_test_hugetlb(folio)) + WARN_ON_ONCE(!folio_test_hugetlb_mte_tagged(folio)); + else + WARN_ON_ONCE(!page_mte_tagged(page)); /* limit access to the end of the page */ offset = offset_in_page(addr); diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 962f985977c2d..e738a353b20e4 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -1055,6 +1055,7 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, void *maddr; unsigned long num_tags; struct page *page; + struct folio *folio; if (is_error_noslot_pfn(pfn)) { ret = -EFAULT; @@ -1068,10 +1069,13 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, ret = -EFAULT; goto out; } + folio = page_folio(page); maddr = page_address(page); if (!write) { - if (page_mte_tagged(page)) + if ((folio_test_hugetlb(folio) && + folio_test_hugetlb_mte_tagged(folio)) || + page_mte_tagged(page)) num_tags = mte_copy_tags_to_user(tags, maddr, MTE_GRANULES_PER_PAGE); else @@ -1085,14 +1089,20 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, * __set_ptes() in the VMM but still overriding the * tags, hence ignoring the return value. */ - try_page_mte_tagging(page); + if (folio_test_hugetlb(folio)) + folio_try_hugetlb_mte_tagging(folio); + else + try_page_mte_tagging(page); num_tags = mte_copy_tags_from_user(maddr, tags, MTE_GRANULES_PER_PAGE); /* uaccess failed, don't leave stale tags */ if (num_tags != MTE_GRANULES_PER_PAGE) mte_clear_page_tags(maddr); - set_page_mte_tagged(page); + if (folio_test_hugetlb(folio)) + folio_set_hugetlb_mte_tagged(folio); + else + set_page_mte_tagged(page); kvm_release_pfn_dirty(pfn); } diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index a509b63bd4dd5..962449f9ac2f9 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1401,10 +1401,21 @@ static void sanitise_mte_tags(struct kvm *kvm, kvm_pfn_t pfn, { unsigned long i, nr_pages = size >> PAGE_SHIFT; struct page *page = pfn_to_page(pfn); + struct folio *folio = page_folio(page); if (!kvm_has_mte(kvm)) return; + if (folio_test_hugetlb(folio)) { + /* Hugetlb has MTE flags set on head page only */ + if (folio_try_hugetlb_mte_tagging(folio)) { + for (i = 0; i < nr_pages; i++, page++) + mte_clear_page_tags(page_address(page)); + folio_set_hugetlb_mte_tagged(folio); + } + return; + } + for (i = 0; i < nr_pages; i++, page++) { if (try_page_mte_tagging(page)) { mte_clear_page_tags(page_address(page)); diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c index a7bb20055ce09..87b3f1a255356 100644 --- a/arch/arm64/mm/copypage.c +++ b/arch/arm64/mm/copypage.c @@ -18,15 +18,40 @@ void copy_highpage(struct page *to, struct page *from) { void *kto = page_address(to); void *kfrom = page_address(from); + struct folio *src = page_folio(from); + struct folio *dst = page_folio(to); + unsigned int i, nr_pages; copy_page(kto, kfrom); if (kasan_hw_tags_enabled()) page_kasan_tag_reset(to); - if (system_supports_mte() && page_mte_tagged(from)) { + if (!system_supports_mte()) + return; + + if (folio_test_hugetlb(src) && + folio_test_hugetlb_mte_tagged(src)) { + if (!folio_try_hugetlb_mte_tagging(dst)) + return; + + /* + * Populate tags for all subpages. + * + * Don't assume the first page is head page since + * huge page copy may start from any subpage. + */ + nr_pages = folio_nr_pages(src); + for (i = 0; i < nr_pages; i++) { + kfrom = page_address(folio_page(src, i)); + kto = page_address(folio_page(dst, i)); + mte_copy_page_tags(kto, kfrom); + } + folio_set_hugetlb_mte_tagged(dst); + } else if (page_mte_tagged(from)) { /* It's a new page, shouldn't have been tagged yet */ WARN_ON_ONCE(!try_page_mte_tagging(to)); + mte_copy_page_tags(kto, kfrom); set_page_mte_tagged(to); } diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 5cf327337e227..f26b3b53d7de4 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -110,7 +110,7 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) * way when do_mmap unwinds (may be important on powerpc * and ia64). */ - vm_flags_set(vma, VM_HUGETLB | VM_DONTEXPAND); + vm_flags_set(vma, VM_HUGETLB | VM_DONTEXPAND | VM_MTE_ALLOWED); vma->vm_ops = &hugetlb_vm_ops; ret = seal_check_write(info->seals, vma);