Merge branch 'akpm' (patches from Andrew)

Merge fixes from Andrew Morton:
"8 fixes"

* emailed patches from Andrew Morton <[e-mail]>:
mm, fs: check for fatal signals in do_generic_file_read()
fs: break out of iomap_file_buffered_write on fatal signals
base/memory, hotplug: fix a kernel oops in show_valid_zones()
mm/memory_hotplug.c: check start_pfn in test_pages_in_a_zone()
jump label: pass kbuild_cflags when checking for asm goto support
shmem: fix sleeping from atomic context
kasan: respect /proc/sys/kernel/traceoff_on_warning
zswap: disable changing params if init fails

Makefile

···
 KBUILD_ARFLAGS := $(call ar-option,D)
 
 # check for 'asm goto'
-ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
+ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y)
 	KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
 	KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
 endif

drivers/base/memory.c

···
 {
 	struct memory_block *mem = to_memory_block(dev);
 	unsigned long start_pfn, end_pfn;
+	unsigned long valid_start, valid_end, valid_pages;
 	unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
-	struct page *first_page;
 	struct zone *zone;
 	int zone_shift = 0;
 
 	start_pfn = section_nr_to_pfn(mem->start_section_nr);
 	end_pfn = start_pfn + nr_pages;
-	first_page = pfn_to_page(start_pfn);
 
 	/* The block contains more than one zone can not be offlined. */
-	if (!test_pages_in_a_zone(start_pfn, end_pfn))
+	if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start, &valid_end))
 		return sprintf(buf, "none\n");
 
-	zone = page_zone(first_page);
+	zone = page_zone(pfn_to_page(valid_start));
+	valid_pages = valid_end - valid_start;
 
 	/* MMOP_ONLINE_KEEP */
 	sprintf(buf, "%s", zone->name);
 
 	/* MMOP_ONLINE_KERNEL */
-	zone_can_shift(start_pfn, nr_pages, ZONE_NORMAL, &zone_shift);
+	zone_can_shift(valid_start, valid_pages, ZONE_NORMAL, &zone_shift);
 	if (zone_shift) {
 		strcat(buf, " ");
 		strcat(buf, (zone + zone_shift)->name);
 	}
 
 	/* MMOP_ONLINE_MOVABLE */
-	zone_can_shift(start_pfn, nr_pages, ZONE_MOVABLE, &zone_shift);
+	zone_can_shift(valid_start, valid_pages, ZONE_MOVABLE, &zone_shift);
 	if (zone_shift) {
 		strcat(buf, " ");
 		strcat(buf, (zone + zone_shift)->name);

fs/dax.c

···
 		struct blk_dax_ctl dax = { 0 };
 		ssize_t map_len;
 
+		if (fatal_signal_pending(current)) {
+			ret = -EINTR;
+			break;
+		}
+
 		dax.sector = dax_iomap_sector(iomap, pos);
 		dax.size = (length + offset + PAGE_SIZE - 1) & PAGE_MASK;
 		map_len = dax_map_atomic(iomap->bdev, &dax);

fs/iomap.c

···
 
 	BUG_ON(pos + len > iomap->offset + iomap->length);
 
+	if (fatal_signal_pending(current))
+		return -EINTR;
+
 	page = grab_cache_page_write_begin(inode->i_mapping, index, flags);
 	if (!page)
 		return -ENOMEM;

include/linux/memory_hotplug.h

···
 extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
 /* VM interface that may be used by firmware interface */
 extern int online_pages(unsigned long, unsigned long, int);
-extern int test_pages_in_a_zone(unsigned long, unsigned long);
+extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
+	unsigned long *valid_start, unsigned long *valid_end);
 extern void __offline_isolated_pages(unsigned long, unsigned long);
 
 typedef void (*online_page_callback_t)(struct page *page);

mm/filemap.c

···
 
 		cond_resched();
 find_page:
+		if (fatal_signal_pending(current)) {
+			error = -EINTR;
+			goto out;
+		}
+
 		page = find_get_page(mapping, index);
 		if (!page) {
 			page_cache_sync_readahead(mapping,

mm/kasan/report.c

···
  *
  */
 
+#include <linux/ftrace.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/printk.h>
···
 
 	if (likely(!kasan_report_enabled()))
 		return;
+
+	disable_trace_on_warning();
 
 	info.access_addr = (void *)addr;
 	info.access_size = size;

mm/memory_hotplug.c

···
 }
 
 /*
- * Confirm all pages in a range [start, end) is belongs to the same zone.
+ * Confirm all pages in a range [start, end) belong to the same zone.
+ * When true, return its valid [start, end).
  */
-int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
+int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
+			 unsigned long *valid_start, unsigned long *valid_end)
 {
 	unsigned long pfn, sec_end_pfn;
+	unsigned long start, end;
 	struct zone *zone = NULL;
 	struct page *page;
 	int i;
-	for (pfn = start_pfn, sec_end_pfn = SECTION_ALIGN_UP(start_pfn);
+	for (pfn = start_pfn, sec_end_pfn = SECTION_ALIGN_UP(start_pfn + 1);
 	     pfn < end_pfn;
-	     pfn = sec_end_pfn + 1, sec_end_pfn += PAGES_PER_SECTION) {
+	     pfn = sec_end_pfn, sec_end_pfn += PAGES_PER_SECTION) {
 		/* Make sure the memory section is present first */
 		if (!present_section_nr(pfn_to_section_nr(pfn)))
 			continue;
···
 			page = pfn_to_page(pfn + i);
 			if (zone && page_zone(page) != zone)
 				return 0;
+			if (!zone)
+				start = pfn + i;
 			zone = page_zone(page);
+			end = pfn + MAX_ORDER_NR_PAGES;
 		}
 	}
-	return 1;
+
+	if (zone) {
+		*valid_start = start;
+		*valid_end = end;
+		return 1;
+	} else {
+		return 0;
+	}
 }
 
 /*
···
 	long offlined_pages;
 	int ret, drain, retry_max, node;
 	unsigned long flags;
+	unsigned long valid_start, valid_end;
 	struct zone *zone;
 	struct memory_notify arg;
 
···
 		return -EINVAL;
 	/* This makes hotplug much easier...and readable.
 	   we assume this for now. .*/
-	if (!test_pages_in_a_zone(start_pfn, end_pfn))
+	if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start, &valid_end))
 		return -EINVAL;
 
-	zone = page_zone(pfn_to_page(start_pfn));
+	zone = page_zone(pfn_to_page(valid_start));
 	node = zone_to_nid(zone);
 	nr_pages = end_pfn - start_pfn;
 

mm/shmem.c

···
 		struct shrink_control *sc, unsigned long nr_to_split)
 {
 	LIST_HEAD(list), *pos, *next;
+	LIST_HEAD(to_remove);
 	struct inode *inode;
 	struct shmem_inode_info *info;
 	struct page *page;
···
 		/* Check if there's anything to gain */
 		if (round_up(inode->i_size, PAGE_SIZE) ==
 				round_up(inode->i_size, HPAGE_PMD_SIZE)) {
-			list_del_init(&info->shrinklist);
+			list_move(&info->shrinklist, &to_remove);
 			removed++;
-			iput(inode);
 			goto next;
 		}
 
···
 			break;
 	}
 	spin_unlock(&sbinfo->shrinklist_lock);
+
+	list_for_each_safe(pos, next, &to_remove) {
+		info = list_entry(pos, struct shmem_inode_info, shrinklist);
+		inode = &info->vfs_inode;
+		list_del_init(&info->shrinklist);
+		iput(inode);
+	}
 
 	list_for_each_safe(pos, next, &list) {
 		int ret;

mm/zswap.c

···
 
 /* Enable/disable zswap (disabled by default) */
 static bool zswap_enabled;
-module_param_named(enabled, zswap_enabled, bool, 0644);
+static int zswap_enabled_param_set(const char *,
+				   const struct kernel_param *);
+static struct kernel_param_ops zswap_enabled_param_ops = {
+	.set =		zswap_enabled_param_set,
+	.get =		param_get_bool,
+};
+module_param_cb(enabled, &zswap_enabled_param_ops, &zswap_enabled, 0644);
 
 /* Crypto compressor to use */
 #define ZSWAP_COMPRESSOR_DEFAULT "lzo"
···
 
 /* used by param callback function */
 static bool zswap_init_started;
+
+/* fatal error during init */
+static bool zswap_init_failed;
 
 /*********************************
 * helpers and fwd declarations
···
 	char *s = strstrip((char *)val);
 	int ret;
 
+	if (zswap_init_failed) {
+		pr_err("can't set param, initialization failed\n");
+		return -ENODEV;
+	}
+
 	/* no change required */
 	if (!strcmp(s, *(char **)kp->arg))
 		return 0;
···
 				 const struct kernel_param *kp)
 {
 	return __zswap_param_set(val, kp, NULL, zswap_compressor);
+}
+
+static int zswap_enabled_param_set(const char *val,
+				   const struct kernel_param *kp)
+{
+	if (zswap_init_failed) {
+		pr_err("can't enable, initialization failed\n");
+		return -ENODEV;
+	}
+
+	return param_set_bool(val, kp);
 }
 
 /*********************************
···
 dstmem_fail:
 	zswap_entry_cache_destroy();
 cache_fail:
+	/* if built-in, we aren't unloaded on failure; don't allow use */
+	zswap_init_failed = true;
+	zswap_enabled = false;
 	return -ENOMEM;
 }
 /* must be late so crypto has time to come up */