From: Liam R. Howlett <Liam.Howlett@Oracle.com>
Date: Tue, 16 Mar 2021 19:56:31 +0000 (-0400)
Subject: s390: gmap, fix rcu lock
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=0d7c9b3843327f3b92cdc6321aa6b1667d1fdcdd;p=users%2Fjedix%2Flinux-maple.git

s390: gmap, fix rcu lock

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
---

diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index d8f3f4d409652..77879744d6523 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -2504,6 +2504,7 @@ static inline void thp_split_mm(struct mm_struct *mm)
 	struct vm_area_struct *vma;
 	MA_STATE(mas, &mm->mm_mt, 0, 0);
 
+	/* Must hold mm_mt lock already */
 	mas_for_each(&mas, vma, ULONG_MAX) {
 		vma->vm_flags &= ~VM_HUGEPAGE;
 		vma->vm_flags |= VM_NOHUGEPAGE;
@@ -2574,6 +2575,7 @@ int gmap_mark_unmergeable(void)
 	int ret;
 	MA_STATE(mas, &mm->mm_mt, 0, 0);
 
+	/* Must hold mm_mt lock already */
 	mas_for_each(&mas, vma, ULONG_MAX) {
 		ret = ksm_madvise(vma, vma->vm_start, vma->vm_end,
 				  MADV_UNMERGEABLE, &vma->vm_flags);