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From: Navid Emamdoost <navid.emamdoost@gmail.com>
To: emamd001@umn.edu
Cc: kjlu@umn.edu, smccaman@umn.edu,
	Navid Emamdoost <navid.emamdoost@gmail.com>,
	Mike Kravetz <mike.kravetz@oracle.com>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: [PATCH] mm/hugetlb.c: check the failure case for find_vma
Date: Wed, 24 Jul 2019 20:39:44 -0500	[thread overview]
Message-ID: <20190725013944.20661-1-navid.emamdoost@gmail.com> (raw)

find_vma may fail and return NULL. The null check is added.

Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
---
 mm/hugetlb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ede7e7f5d1ab..9c5e8b7a6476 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4743,6 +4743,9 @@ void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma,
 pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
 {
 	struct vm_area_struct *vma = find_vma(mm, addr);
+	if (!vma)
+		return (pte_t *)pmd_alloc(mm, pud, addr);
+
 	struct address_space *mapping = vma->vm_file->f_mapping;
 	pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
 			vma->vm_pgoff;
-- 
2.17.1


             reply	other threads:[~2019-07-25  1:40 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-25  1:39 Navid Emamdoost [this message]
2019-07-25 17:53 ` Mike Kravetz
2019-07-25 18:02   ` Navid Emamdoost

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