X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=mm%2Fmemory.c;h=3f8fa06b963b281191ac2c1350af0b21b2dad7c5;hb=a0c9f240a992c4c2b6ac40324ece27475cf3b71a;hp=0f9abbaf618cb8b21ceb7145b53d955a64f462db;hpb=edc315fd222497ae4f4b959a9e31ada1e68a4755;p=~andy%2Flinux

diff --git a/mm/memory.c b/mm/memory.c
index 0f9abbaf618..3f8fa06b963 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -383,30 +383,54 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
 	pmd_t *pmd = pmd_offset(pud, addr);
 	struct address_space *mapping;
 	pgoff_t index;
+	static unsigned long resume;
+	static unsigned long nr_shown;
+	static unsigned long nr_unshown;
+
+	/*
+	 * Allow a burst of 60 reports, then keep quiet for that minute;
+	 * or allow a steady drip of one report per second.
+	 */
+	if (nr_shown == 60) {
+		if (time_before(jiffies, resume)) {
+			nr_unshown++;
+			return;
+		}
+		if (nr_unshown) {
+			printk(KERN_ALERT
+				"BUG: Bad page map: %lu messages suppressed\n",
+				nr_unshown);
+			nr_unshown = 0;
+		}
+		nr_shown = 0;
+	}
+	if (nr_shown++ == 0)
+		resume = jiffies + 60 * HZ;
 
 	mapping = vma->vm_file ? vma->vm_file->f_mapping : NULL;
 	index = linear_page_index(vma, addr);
 
-	printk(KERN_EMERG "Bad page map in process %s  pte:%08llx pmd:%08llx\n",
+	printk(KERN_ALERT
+		"BUG: Bad page map in process %s  pte:%08llx pmd:%08llx\n",
 		current->comm,
 		(long long)pte_val(pte), (long long)pmd_val(*pmd));
 	if (page) {
-		printk(KERN_EMERG
+		printk(KERN_ALERT
 		"page:%p flags:%p count:%d mapcount:%d mapping:%p index:%lx\n",
 		page, (void *)page->flags, page_count(page),
 		page_mapcount(page), page->mapping, page->index);
 	}
-	printk(KERN_EMERG
+	printk(KERN_ALERT
 		"addr:%p vm_flags:%08lx anon_vma:%p mapping:%p index:%lx\n",
 		(void *)addr, vma->vm_flags, vma->anon_vma, mapping, index);
 	/*
 	 * Choose text because data symbols depend on CONFIG_KALLSYMS_ALL=y
 	 */
 	if (vma->vm_ops)
-		print_symbol(KERN_EMERG "vma->vm_ops->fault: %s\n",
+		print_symbol(KERN_ALERT "vma->vm_ops->fault: %s\n",
 				(unsigned long)vma->vm_ops->fault);
 	if (vma->vm_file && vma->vm_file->f_op)
-		print_symbol(KERN_EMERG "vma->vm_file->f_op->mmap: %s\n",
+		print_symbol(KERN_ALERT "vma->vm_file->f_op->mmap: %s\n",
 				(unsigned long)vma->vm_file->f_op->mmap);
 	dump_stack();
 	add_taint(TAINT_BAD_PAGE);
@@ -1186,6 +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;
@@ -1264,12 +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;