---

yaml
---
r: 126246
b: refs/heads/master
c: 4779280
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 91bf189c3a766927694ce9de7d545e96b23f20fc
+refs/heads/master: 4779280d1ea4d361af13ae77ba55217fbcd16d4c

trunk/mm/internal.h

@@ -276,6 +276,7 @@ static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn,
 #define GUP_FLAGS_WRITE                  0x1
 #define GUP_FLAGS_FORCE                  0x2
 #define GUP_FLAGS_IGNORE_VMA_PERMISSIONS 0x4
+#define GUP_FLAGS_IGNORE_SIGKILL         0x8
 
 int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 		     unsigned long start, int len, int flags,

trunk/mm/memory.c

@@ -1210,6 +1210,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 	int write = !!(flags & GUP_FLAGS_WRITE);
 	int force = !!(flags & GUP_FLAGS_FORCE);
 	int ignore = !!(flags & GUP_FLAGS_IGNORE_VMA_PERMISSIONS);
+	int ignore_sigkill = !!(flags & GUP_FLAGS_IGNORE_SIGKILL);
 
 	if (len <= 0)
 		return 0;
@@ -1288,12 +1289,15 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 			struct page *page;
 
 			/*
-			 * If tsk is ooming, cut off its access to large memory
-			 * allocations. It has a pending SIGKILL, but it can't
-			 * be processed until returning to user space.
+			 * If we have a pending SIGKILL, don't keep faulting
+			 * pages and potentially allocating memory, unless
+			 * current is handling munlock--e.g., on exit. In
+			 * that case, we are not allocating memory.  Rather,
+			 * we're only unlocking already resident/mapped pages.
 			 */
-			if (unlikely(test_tsk_thread_flag(tsk, TIF_MEMDIE)))
-				return i ? i : -ENOMEM;
+			if (unlikely(!ignore_sigkill &&
+					fatal_signal_pending(current)))
+				return i ? i : -ERESTARTSYS;
 
 			if (write)
 				foll_flags |= FOLL_WRITE;

trunk/mm/mlock.c

@@ -173,12 +173,13 @@ static long __mlock_vma_pages_range(struct vm_area_struct *vma,
 		  (atomic_read(&mm->mm_users) != 0));
 
 	/*
-	 * mlock:   don't page populate if page has PROT_NONE permission.
-	 * munlock: the pages always do munlock althrough
-	 *          its has PROT_NONE permission.
+	 * mlock:   don't page populate if vma has PROT_NONE permission.
+	 * munlock: always do munlock although the vma has PROT_NONE
+	 *          permission, or SIGKILL is pending.
 	 */
 	if (!mlock)
-		gup_flags |= GUP_FLAGS_IGNORE_VMA_PERMISSIONS;
+		gup_flags |= GUP_FLAGS_IGNORE_VMA_PERMISSIONS |
+			     GUP_FLAGS_IGNORE_SIGKILL;
 
 	if (vma->vm_flags & VM_WRITE)
 		gup_flags |= GUP_FLAGS_WRITE;