From: Suren Baghdasaryan Date: Fri, 11 Nov 2022 18:51:37 +0000 (+0000) Subject: mm: avoid assertion in untrack_pfn X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d54cb91bdebed4756938f1251dbe6080a133394e;p=users%2Fjedix%2Flinux-maple.git mm: avoid assertion in untrack_pfn untrack_pfn can be called after VMA was isolated and mmap_lock downgraded. An attempt to lock affected VMA would cause an assertion, therefore use mod_vm_flags_nolock in such situations. Signed-off-by: Suren Baghdasaryan --- diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c index 926fa2d3d725..b5c82a0c552f 100644 --- a/arch/x86/mm/pat/memtype.c +++ b/arch/x86/mm/pat/memtype.c @@ -1092,7 +1092,7 @@ void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, pfn_t pfn) * can be for the entire vma (in which case pfn, size are zero). */ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, - unsigned long size) + unsigned long size, bool lock_vma) { resource_size_t paddr; unsigned long prot; @@ -1111,8 +1111,12 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, size = vma->vm_end - vma->vm_start; } free_pfn_range(paddr, size); - if (vma) - clear_vm_flags(vma, VM_PAT); + if (vma) { + if (lock_vma) + clear_vm_flags(vma, VM_PAT); + else + mod_vm_flags_nolock(vma, 0, VM_PAT); + } } /* diff --git a/include/linux/mm.h b/include/linux/mm.h index cb2d7f8ae532..17b6aa12c47a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2009,7 +2009,7 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long address, unsigned long size); void unmap_vmas(struct mmu_gather *tlb, struct maple_tree *mt, struct vm_area_struct *start_vma, unsigned long start, - unsigned long end); + unsigned long end, bool lock_vma); struct mmu_notifier_range; diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index a108b60a6962..7bd4274234f3 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1191,7 +1191,8 @@ static inline int track_pfn_copy(struct vm_area_struct *vma) * can be for the entire vma (in which case pfn, size are zero). */ static inline void untrack_pfn(struct vm_area_struct *vma, - unsigned long pfn, unsigned long size) + unsigned long pfn, unsigned long size, + bool lock_vma) { } @@ -1209,7 +1210,7 @@ extern void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, pfn_t pfn); extern int track_pfn_copy(struct vm_area_struct *vma); extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, - unsigned long size); + unsigned long size, bool lock_vma); extern void untrack_pfn_moved(struct vm_area_struct *vma); #endif diff --git a/mm/memory.c b/mm/memory.c index e618481d6b52..b8c2bdf10151 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1658,7 +1658,7 @@ void unmap_page_range(struct mmu_gather *tlb, static void unmap_single_vma(struct mmu_gather *tlb, struct vm_area_struct *vma, unsigned long start_addr, unsigned long end_addr, - struct zap_details *details) + struct zap_details *details, bool lock_vma) { unsigned long start = max(vma->vm_start, start_addr); unsigned long end; @@ -1673,7 +1673,7 @@ static void unmap_single_vma(struct mmu_gather *tlb, uprobe_munmap(vma, start, end); if (unlikely(vma->vm_flags & VM_PFNMAP)) - untrack_pfn(vma, 0, 0); + untrack_pfn(vma, 0, 0, lock_vma); if (start != end) { if (unlikely(is_vm_hugetlb_page(vma))) { @@ -1720,7 +1720,7 @@ static void unmap_single_vma(struct mmu_gather *tlb, */ void unmap_vmas(struct mmu_gather *tlb, struct maple_tree *mt, struct vm_area_struct *vma, unsigned long start_addr, - unsigned long end_addr) + unsigned long end_addr, bool lock_vma) { struct mmu_notifier_range range; struct zap_details details = { @@ -1734,7 +1734,8 @@ void unmap_vmas(struct mmu_gather *tlb, struct maple_tree *mt, start_addr, end_addr); mmu_notifier_invalidate_range_start(&range); do { - unmap_single_vma(tlb, vma, start_addr, end_addr, &details); + unmap_single_vma(tlb, vma, start_addr, end_addr, &details, + lock_vma); } while ((vma = mas_find(&mas, end_addr - 1)) != NULL); mmu_notifier_invalidate_range_end(&range); } @@ -1763,7 +1764,7 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long start, update_hiwater_rss(vma->vm_mm); mmu_notifier_invalidate_range_start(&range); do { - unmap_single_vma(&tlb, vma, start, range.end, NULL); + unmap_single_vma(&tlb, vma, start, range.end, NULL, false); } while ((vma = mas_find(&mas, end - 1)) != NULL); mmu_notifier_invalidate_range_end(&range); tlb_finish_mmu(&tlb); @@ -1790,7 +1791,7 @@ static void zap_page_range_single(struct vm_area_struct *vma, unsigned long addr tlb_gather_mmu(&tlb, vma->vm_mm); update_hiwater_rss(vma->vm_mm); mmu_notifier_invalidate_range_start(&range); - unmap_single_vma(&tlb, vma, address, range.end, details); + unmap_single_vma(&tlb, vma, address, range.end, details, false); mmu_notifier_invalidate_range_end(&range); tlb_finish_mmu(&tlb); } @@ -2559,7 +2560,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, err = remap_pfn_range_notrack(vma, addr, pfn, size, prot); if (err) - untrack_pfn(vma, pfn, PAGE_ALIGN(size)); + untrack_pfn(vma, pfn, PAGE_ALIGN(size), true); return err; } EXPORT_SYMBOL(remap_pfn_range); diff --git a/mm/memremap.c b/mm/memremap.c index 08cbf54fe037..2f88f43d4a01 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -129,7 +129,7 @@ static void pageunmap_range(struct dev_pagemap *pgmap, int range_id) } mem_hotplug_done(); - untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range)); + untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range), true); pgmap_array_delete(range); } @@ -276,7 +276,7 @@ err_add_memory: if (!is_private) kasan_remove_zero_shadow(__va(range->start), range_len(range)); err_kasan: - untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range)); + untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range), true); err_pfn_remap: pgmap_array_delete(range); return error; diff --git a/mm/mmap.c b/mm/mmap.c index 60412fe3114d..f0c6f122a60b 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2219,7 +2219,7 @@ static void unmap_region(struct mm_struct *mm, struct maple_tree *mt, lru_add_drain(); tlb_gather_mmu(&tlb, mm); update_hiwater_rss(mm); - unmap_vmas(&tlb, mt, vma, start, end); + unmap_vmas(&tlb, mt, vma, start, end, lock_vma); free_pgtables(&tlb, mt, vma, prev ? prev->vm_end : FIRST_USER_ADDRESS, next ? next->vm_start : USER_PGTABLES_CEILING, lock_vma); @@ -3142,7 +3142,7 @@ void exit_mmap(struct mm_struct *mm) tlb_gather_mmu_fullmm(&tlb, mm); /* update_hiwater_rss(mm) here? but nobody should be looking */ /* Use ULONG_MAX here to ensure all VMAs in the mm are unmapped */ - unmap_vmas(&tlb, &mm->mm_mt, vma, 0, ULONG_MAX); + unmap_vmas(&tlb, &mm->mm_mt, vma, 0, ULONG_MAX, false); mmap_read_unlock(mm); /*