From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Fri, 16 Jun 2023 17:55:11 +0000 (-0400)
Subject: attempt 2
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=refs%2Fheads%2Fv6.4-rc5_stack;p=users%2Fjedix%2Flinux-maple.git

attempt 2

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

diff --git a/mm/memory.c b/mm/memory.c
index 44d10fa417be..a9b587633878 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -5349,19 +5349,14 @@ struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm,
 		return NULL;
 	}
 	err = expand_stack(vma, addr, false);
-	if (unlikely(err)){
-		if (err != -EAGAIN) {
-			mmap_read_unlock(mm);
-			return NULL;
-		}
+	if (err == -EAGAIN){
 		if (!upgrade_mmap_lock_carefully(mm, regs))
 			return NULL;
-		vma = find_vma(mm, addr);
-		if (!vma || expand_stack(vma, addr, true)) {
-			mmap_write_unlock(mm);
-			return NULL;
-		}
+		vma = find_extend_vma_locked(mm, addr, true);
 		mmap_write_downgrade(mm);
+	} else if (err) {
+		mmap_read_unlock(mm);
+		return NULL;
 	}
 	return vma;
 }
@@ -5416,9 +5411,7 @@ struct vm_area_struct *find_extend_vma_locked(struct mm_struct *mm,
 		return vma;
 	start = vma->vm_start;
 	err = expand_stack(vma, addr, write_locked);
-	if (unlikely(err)) {
-		if (err != -EAGAIN)
-			return NULL;
+	if (err == -EAGAIN) {
 		if (!upgrade_mmap_lock_carefully(mm, NULL))
 			return NULL;
 		vma = find_vma(mm, addr);
@@ -5427,6 +5420,8 @@ struct vm_area_struct *find_extend_vma_locked(struct mm_struct *mm,
 			return NULL;
 		}
 		mmap_write_downgrade(mm);
+	} else if (err) {
+		return NULL;
 	}
 	if (vma->vm_flags & VM_LOCKED)
 		populate_vma_page_range(vma, addr, start, NULL);