From 0182a438f560af8103cda9d9406c745154638b9b Mon Sep 17 00:00:00 2001
From: Linus Torvalds <torvalds@home.osdl.org>
Date: Tue, 7 Oct 2003 18:59:34 -0700
Subject: [PATCH] Revert the move of ptrinfo - it may make NOMMU compile, but
 it breaks everybody else.

Instead, fix the NOMMU case by avoiding the part that walks page
tables.
---
 mm/memory.c | 73 ---------------------------------------------------
 mm/slab.c   | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+), 73 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index 561c6fb9ea36f..ab34c145d4c3b 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1701,76 +1701,3 @@ struct page * vmalloc_to_page(void * vmalloc_addr)
 }
 
 EXPORT_SYMBOL(vmalloc_to_page);
-
-void ptrinfo(unsigned long addr)
-{
-	struct page *page;
-
-	printk("Dumping data about address %p.\n", (void*)addr);
-	if (!virt_addr_valid((void*)addr)) {
-		printk("virt addr invalid.\n");
-		return;
-	}
-	do {
-		pgd_t *pgd = pgd_offset_k(addr);
-		pmd_t *pmd;
-		if (pgd_none(*pgd)) {
-			printk("No pgd.\n");
-			break;
-		}
-		pmd = pmd_offset(pgd, addr);
-		if (pmd_none(*pmd)) {
-			printk("No pmd.\n");
-			break;
-		}
-#ifdef CONFIG_X86
-		if (pmd_large(*pmd)) {
-			printk("Large page.\n");
-			break;
-		}
-#endif
-		printk("normal page, pte_val 0x%llx\n",
-		  (unsigned long long)pte_val(*pte_offset_kernel(pmd, addr)));
-	} while(0);
-
-	page = virt_to_page((void*)addr);
-	printk("struct page at %p, flags %lxh.\n", page, page->flags);
-	if (PageSlab(page)) {
-		kmem_cache_t *c;
-		struct slab *s;
-		unsigned long flags;
-		int objnr;
-		void *objp;
-
-		c = GET_PAGE_CACHE(page);
-		printk("belongs to cache %s.\n",c->name);
-
-		spin_lock_irqsave(&c->spinlock, flags);
-		s = GET_PAGE_SLAB(page);
-		printk("slabp %p with %d inuse objects (from %d).\n",
-			s, s->inuse, c->num);
-		check_slabp(c,s);
-
-		objnr = (addr-(unsigned long)s->s_mem)/c->objsize;
-		objp = s->s_mem+c->objsize*objnr;
-		printk("points into object no %d, starting at %p, len %d.\n",
-			objnr, objp, c->objsize);
-		if (objnr >= c->num) {
-			printk("Bad obj number.\n");
-		} else {
-			kernel_map_pages(virt_to_page(objp),
-					c->objsize/PAGE_SIZE, 1);
-
-			if (c->flags & SLAB_RED_ZONE)
-				printk("redzone: 0x%lx/0x%lx.\n",
-					*dbg_redzone1(c, objp),
-					*dbg_redzone2(c, objp));
-
-			if (c->flags & SLAB_STORE_USER)
-				printk("Last user: %p.\n",
-					*dbg_userword(c, objp));
-		}
-		spin_unlock_irqrestore(&c->spinlock, flags);
-
-	}
-}
diff --git a/mm/slab.c b/mm/slab.c
index 5c8f98e5a93aa..7838f7f4dfc80 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2763,3 +2763,78 @@ unsigned int ksize(const void *objp)
 
 	return size;
 }
+
+void ptrinfo(unsigned long addr)
+{
+	struct page *page;
+
+	printk("Dumping data about address %p.\n", (void*)addr);
+	if (!virt_addr_valid((void*)addr)) {
+		printk("virt addr invalid.\n");
+		return;
+	}
+#ifdef CONFIG_MMU
+	do {
+		pgd_t *pgd = pgd_offset_k(addr);
+		pmd_t *pmd;
+		if (pgd_none(*pgd)) {
+			printk("No pgd.\n");
+			break;
+		}
+		pmd = pmd_offset(pgd, addr);
+		if (pmd_none(*pmd)) {
+			printk("No pmd.\n");
+			break;
+		}
+#ifdef CONFIG_X86
+		if (pmd_large(*pmd)) {
+			printk("Large page.\n");
+			break;
+		}
+#endif
+		printk("normal page, pte_val 0x%llx\n",
+		  (unsigned long long)pte_val(*pte_offset_kernel(pmd, addr)));
+	} while(0);
+#endif
+
+	page = virt_to_page((void*)addr);
+	printk("struct page at %p, flags %lxh.\n", page, page->flags);
+	if (PageSlab(page)) {
+		kmem_cache_t *c;
+		struct slab *s;
+		unsigned long flags;
+		int objnr;
+		void *objp;
+
+		c = GET_PAGE_CACHE(page);
+		printk("belongs to cache %s.\n",c->name);
+
+		spin_lock_irqsave(&c->spinlock, flags);
+		s = GET_PAGE_SLAB(page);
+		printk("slabp %p with %d inuse objects (from %d).\n",
+			s, s->inuse, c->num);
+		check_slabp(c,s);
+
+		objnr = (addr-(unsigned long)s->s_mem)/c->objsize;
+		objp = s->s_mem+c->objsize*objnr;
+		printk("points into object no %d, starting at %p, len %d.\n",
+			objnr, objp, c->objsize);
+		if (objnr >= c->num) {
+			printk("Bad obj number.\n");
+		} else {
+			kernel_map_pages(virt_to_page(objp),
+					c->objsize/PAGE_SIZE, 1);
+
+			if (c->flags & SLAB_RED_ZONE)
+				printk("redzone: 0x%lx/0x%lx.\n",
+					*dbg_redzone1(c, objp),
+					*dbg_redzone2(c, objp));
+
+			if (c->flags & SLAB_STORE_USER)
+				printk("Last user: %p.\n",
+					*dbg_userword(c, objp));
+		}
+		spin_unlock_irqrestore(&c->spinlock, flags);
+
+	}
+}
-- 
2.53.0