[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20230803172652.2849981-4-surenb@google.com>
Date: Thu, 3 Aug 2023 10:26:48 -0700
From: Suren Baghdasaryan <surenb@...gle.com>
To: akpm@...ux-foundation.org
Cc: torvalds@...ux-foundation.org, jannh@...gle.com,
willy@...radead.org, liam.howlett@...cle.com, david@...hat.com,
peterx@...hat.com, ldufour@...ux.ibm.com, vbabka@...e.cz,
michel@...pinasse.org, jglisse@...gle.com, mhocko@...e.com,
hannes@...xchg.org, dave@...olabs.net, hughd@...gle.com,
linux-kernel@...r.kernel.org, linux-mm@...ck.org,
stable@...r.kernel.org, Suren Baghdasaryan <surenb@...gle.com>,
"Liam R . Howlett" <Liam.Howlett@...cle.com>
Subject: [PATCH v3 3/6] mm: replace mmap with vma write lock assertions when
operating on a vma
Vma write lock assertion always includes mmap write lock assertion and
additional vma lock checks when per-VMA locks are enabled. Replace
weaker mmap_assert_write_locked() assertions with stronger
vma_assert_write_locked() ones when we are operating on a vma which
is expected to be locked.
Suggested-by: Jann Horn <jannh@...gle.com>
Signed-off-by: Suren Baghdasaryan <surenb@...gle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@...cle.com>
---
mm/hugetlb.c | 2 +-
mm/khugepaged.c | 5 +++--
mm/memory.c | 2 +-
3 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 64a3239b6407..1d871a1167d8 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5028,7 +5028,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
src_vma->vm_start,
src_vma->vm_end);
mmu_notifier_invalidate_range_start(&range);
- mmap_assert_write_locked(src);
+ vma_assert_write_locked(src_vma);
raw_write_seqcount_begin(&src->write_protect_seq);
} else {
/*
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 78c8d5d8b628..1e43a56fba31 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1495,7 +1495,7 @@ static int set_huge_pmd(struct vm_area_struct *vma, unsigned long addr,
};
VM_BUG_ON(!PageTransHuge(hpage));
- mmap_assert_write_locked(vma->vm_mm);
+ vma_assert_write_locked(vma);
if (do_set_pmd(&vmf, hpage))
return SCAN_FAIL;
@@ -1525,7 +1525,7 @@ static void collapse_and_free_pmd(struct mm_struct *mm, struct vm_area_struct *v
pmd_t pmd;
struct mmu_notifier_range range;
- mmap_assert_write_locked(mm);
+ vma_assert_write_locked(vma);
if (vma->vm_file)
lockdep_assert_held_write(&vma->vm_file->f_mapping->i_mmap_rwsem);
/*
@@ -1570,6 +1570,7 @@ int collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr,
int count = 0, result = SCAN_FAIL;
int i;
+ /* Ensure vma can't change, it will be locked below after checks */
mmap_assert_write_locked(mm);
/* Fast check before locking page if already PMD-mapped */
diff --git a/mm/memory.c b/mm/memory.c
index 603b2f419948..652d99b9858a 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1312,7 +1312,7 @@ copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma)
* Use the raw variant of the seqcount_t write API to avoid
* lockdep complaining about preemptibility.
*/
- mmap_assert_write_locked(src_mm);
+ vma_assert_write_locked(src_vma);
raw_write_seqcount_begin(&src_mm->write_protect_seq);
}
--
2.41.0.585.gd2178a4bd4-goog
Powered by blists - more mailing lists