Re: [PATCH] mm/huge_memory.c: use helper range_in_vma() in __split_huge_p[u|m]d_locked()

From: David Hildenbrand
Date: Mon Feb 01 2021 - 05:56:47 EST


On 01.02.21 10:32, Miaohe Lin wrote:
The helper range_in_vma() is introduced via commit 017b1660df89 ("mm:
migration: fix migration of huge PMD shared pages"). But we forgot to
use it in __split_huge_pud_locked() and __split_huge_pmd_locked().

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
mm/huge_memory.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 987cf5e4cf90..33353a4f95fb 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1959,8 +1959,7 @@ static void __split_huge_pud_locked(struct vm_area_struct *vma, pud_t *pud,
unsigned long haddr)
{
VM_BUG_ON(haddr & ~HPAGE_PUD_MASK);
- VM_BUG_ON_VMA(vma->vm_start > haddr, vma);
- VM_BUG_ON_VMA(vma->vm_end < haddr + HPAGE_PUD_SIZE, vma);
+ VM_BUG_ON_VMA(!range_in_vma(vma, haddr, haddr + HPAGE_PUD_SIZE), vma);
VM_BUG_ON(!pud_trans_huge(*pud) && !pud_devmap(*pud));
count_vm_event(THP_SPLIT_PUD);
@@ -2039,8 +2038,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd,
int i;
VM_BUG_ON(haddr & ~HPAGE_PMD_MASK);
- VM_BUG_ON_VMA(vma->vm_start > haddr, vma);
- VM_BUG_ON_VMA(vma->vm_end < haddr + HPAGE_PMD_SIZE, vma);
+ VM_BUG_ON_VMA(!range_in_vma(vma, haddr, haddr + HPAGE_PMD_SIZE), vma);
VM_BUG_ON(!is_pmd_migration_entry(*pmd) && !pmd_trans_huge(*pmd)
&& !pmd_devmap(*pmd));


Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

--
Thanks,

David / dhildenb