Merge tag 's390-5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Heiko Carstens:

 - Add missing Kconfig option for ftrace direct multi sample, so it can
   be compiled again, and also add s390 support for this sample.

 - Update Christian Borntraeger's email address.

 - Various fixes for memory layout setup. Besides other this makes it
   possible to load shared DCSS segments again.

 - Fix copy to user space of swapped kdump oldmem.

 - Remove -mstack-guard and -mstack-size compile options when building
   vdso binaries. This can happen when CONFIG_VMAP_STACK is disabled and
   results in broken vdso code which causes more or less random
   exceptions. Also remove the not needed -nostdlib option.

 - Fix memory leak on cpu hotplug and return code handling in kexec
   code.

 - Wire up futex_waitv system call.

 - Replace snprintf with sysfs_emit where appropriate.

* tag 's390-5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  ftrace/samples: add s390 support for ftrace direct multi sample
  ftrace/samples: add missing Kconfig option for ftrace direct multi sample
  MAINTAINERS: update email address of Christian Borntraeger
  s390/kexec: fix memory leak of ipl report buffer
  s390/kexec: fix return code handling
  s390/dump: fix copying to user-space of swapped kdump oldmem
  s390: wire up sys_futex_waitv system call
  s390/vdso: filter out -mstack-guard and -mstack-size
  s390/vdso: remove -nostdlib compiler flag
  s390: replace snprintf in show functions with sysfs_emit
  s390/boot: simplify and fix kernel memory layout setup
  s390/setup: re-arrange memblock setup
  s390/setup: avoid using memblock_enforce_memory_limit
  s390/setup: avoid reserving memory above identity mapping

.mailmap

@@ -71,6 +71,9 @@ Chao Yu <chao@kernel.org> <chao2.yu@samsung.com>
 Chao Yu <chao@kernel.org> <yuchao0@huawei.com>
 Chris Chiu <chris.chiu@canonical.com> <chiu@endlessm.com>
 Chris Chiu <chris.chiu@canonical.com> <chiu@endlessos.org>
+Christian Borntraeger <borntraeger@linux.ibm.com> <borntraeger@de.ibm.com>
+Christian Borntraeger <borntraeger@linux.ibm.com> <cborntra@de.ibm.com>
+Christian Borntraeger <borntraeger@linux.ibm.com> <borntrae@de.ibm.com>
 Christophe Ricard <christophe.ricard@gmail.com>
 Christoph Hellwig <hch@lst.de>
 Colin Ian King <colin.king@intel.com> <colin.king@canonical.com>

MAINTAINERS

@@ -10445,7 +10445,7 @@ F:	arch/riscv/include/uapi/asm/kvm*
 F:	arch/riscv/kvm/
 
 KERNEL VIRTUAL MACHINE for s390 (KVM/s390)
-M:	Christian Borntraeger <borntraeger@de.ibm.com>
+M:	Christian Borntraeger <borntraeger@linux.ibm.com>
 M:	Janosch Frank <frankja@linux.ibm.com>
 R:	David Hildenbrand <david@redhat.com>
 R:	Claudio Imbrenda <imbrenda@linux.ibm.com>
@@ -16573,7 +16573,7 @@ F:	drivers/video/fbdev/savage/
 S390
 M:	Heiko Carstens <hca@linux.ibm.com>
 M:	Vasily Gorbik <gor@linux.ibm.com>
-M:	Christian Borntraeger <borntraeger@de.ibm.com>
+M:	Christian Borntraeger <borntraeger@linux.ibm.com>
 R:	Alexander Gordeev <agordeev@linux.ibm.com>
 L:	linux-s390@vger.kernel.org
 S:	Supported

arch/s390/Kconfig

@@ -47,7 +47,7 @@ config ARCH_SUPPORTS_UPROBES
 config KASAN_SHADOW_OFFSET
 	hex
 	depends on KASAN
-	default 0x18000000000000
+	default 0x1C000000000000
 
 config S390
 	def_bool y
@@ -194,6 +194,7 @@ config S390
 	select HAVE_RELIABLE_STACKTRACE
 	select HAVE_RSEQ
 	select HAVE_SAMPLE_FTRACE_DIRECT
+	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
 	select HAVE_SOFTIRQ_ON_OWN_STACK
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_VIRT_CPU_ACCOUNTING

arch/s390/Makefile

@@ -77,10 +77,12 @@ KBUILD_AFLAGS_DECOMPRESSOR += $(aflags-y)
 KBUILD_CFLAGS_DECOMPRESSOR += $(cflags-y)
 
 ifneq ($(call cc-option,-mstack-size=8192 -mstack-guard=128),)
-cflags-$(CONFIG_CHECK_STACK) += -mstack-size=$(STACK_SIZE)
-ifeq ($(call cc-option,-mstack-size=8192),)
-cflags-$(CONFIG_CHECK_STACK) += -mstack-guard=$(CONFIG_STACK_GUARD)
-endif
+  CC_FLAGS_CHECK_STACK := -mstack-size=$(STACK_SIZE)
+  ifeq ($(call cc-option,-mstack-size=8192),)
+    CC_FLAGS_CHECK_STACK += -mstack-guard=$(CONFIG_STACK_GUARD)
+  endif
+  export CC_FLAGS_CHECK_STACK
+  cflags-$(CONFIG_CHECK_STACK) += $(CC_FLAGS_CHECK_STACK)
 endif
 
 ifdef CONFIG_EXPOLINE

arch/s390/boot/startup.c

@@ -149,82 +149,56 @@ static void setup_ident_map_size(unsigned long max_physmem_end)
 
 static void setup_kernel_memory_layout(void)
 {
-	bool vmalloc_size_verified = false;
-	unsigned long vmemmap_off;
-	unsigned long vspace_left;
+	unsigned long vmemmap_start;
 	unsigned long rte_size;
 	unsigned long pages;
-	unsigned long vmax;
 
 	pages = ident_map_size / PAGE_SIZE;
 	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
 	vmemmap_size = SECTION_ALIGN_UP(pages) * sizeof(struct page);
 
 	/* choose kernel address space layout: 4 or 3 levels. */
-	vmemmap_off = round_up(ident_map_size, _REGION3_SIZE);
+	vmemmap_start = round_up(ident_map_size, _REGION3_SIZE);
 	if (IS_ENABLED(CONFIG_KASAN) ||
 	    vmalloc_size > _REGION2_SIZE ||
-	    vmemmap_off + vmemmap_size + vmalloc_size + MODULES_LEN > _REGION2_SIZE)
-		vmax = _REGION1_SIZE;
-	else
-		vmax = _REGION2_SIZE;
-
-	/* keep vmemmap_off aligned to a top level region table entry */
-	rte_size = vmax == _REGION1_SIZE ? _REGION2_SIZE : _REGION3_SIZE;
-	MODULES_END = vmax;
-	if (is_prot_virt_host()) {
-		/*
-		 * forcing modules and vmalloc area under the ultravisor
-		 * secure storage limit, so that any vmalloc allocation
-		 * we do could be used to back secure guest storage.
-		 */
-		adjust_to_uv_max(&MODULES_END);
-	}
-
-#ifdef CONFIG_KASAN
-	if (MODULES_END < vmax) {
-		/* force vmalloc and modules below kasan shadow */
-		MODULES_END = min(MODULES_END, KASAN_SHADOW_START);
+	    vmemmap_start + vmemmap_size + vmalloc_size + MODULES_LEN >
+		    _REGION2_SIZE) {
+		MODULES_END = _REGION1_SIZE;
+		rte_size = _REGION2_SIZE;
 	} else {
-		/*
-		 * leave vmalloc and modules above kasan shadow but make
-		 * sure they don't overlap with it
-		 */
-		vmalloc_size = min(vmalloc_size, vmax - KASAN_SHADOW_END - MODULES_LEN);
-		vmalloc_size_verified = true;
-		vspace_left = KASAN_SHADOW_START;
+		MODULES_END = _REGION2_SIZE;
+		rte_size = _REGION3_SIZE;
 	}
+	/*
+	 * forcing modules and vmalloc area under the ultravisor
+	 * secure storage limit, so that any vmalloc allocation
+	 * we do could be used to back secure guest storage.
+	 */
+	adjust_to_uv_max(&MODULES_END);
+#ifdef CONFIG_KASAN
+	/* force vmalloc and modules below kasan shadow */
+	MODULES_END = min(MODULES_END, KASAN_SHADOW_START);
 #endif
 	MODULES_VADDR = MODULES_END - MODULES_LEN;
 	VMALLOC_END = MODULES_VADDR;
 
-	if (vmalloc_size_verified) {
-		VMALLOC_START = VMALLOC_END - vmalloc_size;
-	} else {
-		vmemmap_off = round_up(ident_map_size, rte_size);
-
-		if (vmemmap_off + vmemmap_size > VMALLOC_END ||
-		    vmalloc_size > VMALLOC_END - vmemmap_off - vmemmap_size) {
-			/*
-			 * allow vmalloc area to occupy up to 1/2 of
-			 * the rest virtual space left.
-			 */
-			vmalloc_size = min(vmalloc_size, VMALLOC_END / 2);
-		}
-		VMALLOC_START = VMALLOC_END - vmalloc_size;
-		vspace_left = VMALLOC_START;
-	}
+	/* allow vmalloc area to occupy up to about 1/2 of the rest virtual space left */
+	vmalloc_size = min(vmalloc_size, round_down(VMALLOC_END / 2, _REGION3_SIZE));
+	VMALLOC_START = VMALLOC_END - vmalloc_size;
 
-	pages = vspace_left / (PAGE_SIZE + sizeof(struct page));
+	/* split remaining virtual space between 1:1 mapping & vmemmap array */
+	pages = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
 	pages = SECTION_ALIGN_UP(pages);
-	vmemmap_off = round_up(vspace_left - pages * sizeof(struct page), rte_size);
-	/* keep vmemmap left most starting from a fresh region table entry */
-	vmemmap_off = min(vmemmap_off, round_up(ident_map_size, rte_size));
-	/* take care that identity map is lower then vmemmap */
-	ident_map_size = min(ident_map_size, vmemmap_off);
+	/* keep vmemmap_start aligned to a top level region table entry */
+	vmemmap_start = round_down(VMALLOC_START - pages * sizeof(struct page), rte_size);
+	/* vmemmap_start is the future VMEM_MAX_PHYS, make sure it is within MAX_PHYSMEM */
+	vmemmap_start = min(vmemmap_start, 1UL << MAX_PHYSMEM_BITS);
+	/* make sure identity map doesn't overlay with vmemmap */
+	ident_map_size = min(ident_map_size, vmemmap_start);
 	vmemmap_size = SECTION_ALIGN_UP(ident_map_size / PAGE_SIZE) * sizeof(struct page);
-	VMALLOC_START = max(vmemmap_off + vmemmap_size, VMALLOC_START);
-	vmemmap = (struct page *)vmemmap_off;
+	/* make sure vmemmap doesn't overlay with vmalloc area */
+	VMALLOC_START = max(vmemmap_start + vmemmap_size, VMALLOC_START);
+	vmemmap = (struct page *)vmemmap_start;
 }
 
 /*

arch/s390/include/asm/kexec.h

@@ -74,6 +74,12 @@ void *kexec_file_add_components(struct kimage *image,
 int arch_kexec_do_relocs(int r_type, void *loc, unsigned long val,
 			 unsigned long addr);
 
+#define ARCH_HAS_KIMAGE_ARCH
+
+struct kimage_arch {
+	void *ipl_buf;
+};
+
 extern const struct kexec_file_ops s390_kexec_image_ops;
 extern const struct kexec_file_ops s390_kexec_elf_ops;
 

arch/s390/kernel/crash_dump.c

@@ -191,8 +191,8 @@ static int copy_oldmem_user(void __user *dst, void *src, size_t count)
 				return rc;
 		} else {
 			/* Check for swapped kdump oldmem areas */
-			if (oldmem_data.start && from - oldmem_data.size < oldmem_data.size) {
-				from -= oldmem_data.size;
+			if (oldmem_data.start && from - oldmem_data.start < oldmem_data.size) {
+				from -= oldmem_data.start;
 				len = min(count, oldmem_data.size - from);
 			} else if (oldmem_data.start && from < oldmem_data.size) {
 				len = min(count, oldmem_data.size - from);

arch/s390/kernel/ipl.c

@@ -2156,7 +2156,7 @@ void *ipl_report_finish(struct ipl_report *report)
 
 	buf = vzalloc(report->size);
 	if (!buf)
-		return ERR_PTR(-ENOMEM);
+		goto out;
 	ptr = buf;
 
 	memcpy(ptr, report->ipib, report->ipib->hdr.len);
@@ -2195,6 +2195,7 @@ void *ipl_report_finish(struct ipl_report *report)
 	}
 
 	BUG_ON(ptr > buf + report->size);
+out:
 	return buf;
 }
 

arch/s390/kernel/machine_kexec_file.c

@@ -12,6 +12,7 @@
 #include <linux/kexec.h>
 #include <linux/module_signature.h>
 #include <linux/verification.h>
+#include <linux/vmalloc.h>
 #include <asm/boot_data.h>
 #include <asm/ipl.h>
 #include <asm/setup.h>
@@ -170,6 +171,7 @@ static int kexec_file_add_ipl_report(struct kimage *image,
 	struct kexec_buf buf;
 	unsigned long addr;
 	void *ptr, *end;
+	int ret;
 
 	buf.image = image;
 
@@ -199,9 +201,13 @@ static int kexec_file_add_ipl_report(struct kimage *image,
 		ptr += len;
 	}
 
+	ret = -ENOMEM;
 	buf.buffer = ipl_report_finish(data->report);
+	if (!buf.buffer)
+		goto out;
 	buf.bufsz = data->report->size;
 	buf.memsz = buf.bufsz;
+	image->arch.ipl_buf = buf.buffer;
 
 	data->memsz += buf.memsz;
 
@@ -209,7 +215,9 @@ static int kexec_file_add_ipl_report(struct kimage *image,
 		data->kernel_buf + offsetof(struct lowcore, ipl_parmblock_ptr);
 	*lc_ipl_parmblock_ptr = (__u32)buf.mem;
 
-	return kexec_add_buffer(&buf);
+	ret = kexec_add_buffer(&buf);
+out:
+	return ret;
 }
 
 void *kexec_file_add_components(struct kimage *image,
@@ -322,3 +330,11 @@ int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
 	}
 	return 0;
 }
+
+int arch_kimage_file_post_load_cleanup(struct kimage *image)
+{
+	vfree(image->arch.ipl_buf);
+	image->arch.ipl_buf = NULL;
+
+	return kexec_image_post_load_cleanup_default(image);
+}

arch/s390/kernel/setup.c

@@ -606,7 +606,7 @@ static void __init setup_resources(void)
 
 static void __init setup_memory_end(void)
 {
-	memblock_remove(ident_map_size, ULONG_MAX);
+	memblock_remove(ident_map_size, PHYS_ADDR_MAX - ident_map_size);
 	max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 	pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 }
@@ -637,14 +637,6 @@ static struct notifier_block kdump_mem_nb = {
 
 #endif
 
-/*
- * Make sure that the area above identity mapping is protected
- */
-static void __init reserve_above_ident_map(void)
-{
-	memblock_reserve(ident_map_size, ULONG_MAX);
-}
-
 /*
  * Reserve memory for kdump kernel to be loaded with kexec
  */
@@ -785,7 +777,6 @@ static void __init memblock_add_mem_detect_info(void)
 	}
 	memblock_set_bottom_up(false);
 	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
-	memblock_dump_all();
 }
 
 /*
@@ -826,9 +817,6 @@ static void __init setup_memory(void)
 		storage_key_init_range(start, end);
 
 	psw_set_key(PAGE_DEFAULT_KEY);
-
-	/* Only cosmetics */
-	memblock_enforce_memory_limit(memblock_end_of_DRAM());
 }
 
 static void __init relocate_amode31_section(void)
@@ -999,24 +987,24 @@ void __init setup_arch(char **cmdline_p)
 	setup_control_program_code();
 
 	/* Do some memory reservations *before* memory is added to memblock */
-	reserve_above_ident_map();
 	reserve_kernel();
 	reserve_initrd();
 	reserve_certificate_list();
 	reserve_mem_detect_info();
+	memblock_set_current_limit(ident_map_size);
 	memblock_allow_resize();
 
 	/* Get information about *all* installed memory */
 	memblock_add_mem_detect_info();
 
 	free_mem_detect_info();
+	setup_memory_end();
+	memblock_dump_all();
+	setup_memory();
 
 	relocate_amode31_section();
 	setup_cr();
-
 	setup_uv();
-	setup_memory_end();
-	setup_memory();
 	dma_contiguous_reserve(ident_map_size);
 	vmcp_cma_reserve();
 	if (MACHINE_HAS_EDAT2)

arch/s390/kernel/syscalls/syscall.tbl

@@ -451,3 +451,4 @@
 446  common	landlock_restrict_self	sys_landlock_restrict_self	sys_landlock_restrict_self
 # 447 reserved for memfd_secret
 448  common	process_mrelease	sys_process_mrelease		sys_process_mrelease
+449  common	futex_waitv		sys_futex_waitv			sys_futex_waitv

arch/s390/kernel/vdso32/Makefile

@@ -22,7 +22,7 @@ KBUILD_AFLAGS_32 += -m31 -s
 KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
 KBUILD_CFLAGS_32 += -m31 -fPIC -shared -fno-common -fno-builtin
 
-LDFLAGS_vdso32.so.dbg += -fPIC -shared -nostdlib -soname=linux-vdso32.so.1 \
+LDFLAGS_vdso32.so.dbg += -fPIC -shared -soname=linux-vdso32.so.1 \
 	--hash-style=both --build-id=sha1 -melf_s390 -T
 
 $(targets:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)

arch/s390/kernel/vdso64/Makefile

@@ -8,8 +8,9 @@ ARCH_REL_TYPE_ABS += R_390_GOT|R_390_PLT
 include $(srctree)/lib/vdso/Makefile
 obj-vdso64 = vdso_user_wrapper.o note.o
 obj-cvdso64 = vdso64_generic.o getcpu.o
-CFLAGS_REMOVE_getcpu.o = -pg $(CC_FLAGS_FTRACE) $(CC_FLAGS_EXPOLINE)
-CFLAGS_REMOVE_vdso64_generic.o = -pg $(CC_FLAGS_FTRACE) $(CC_FLAGS_EXPOLINE)
+VDSO_CFLAGS_REMOVE := -pg $(CC_FLAGS_FTRACE) $(CC_FLAGS_EXPOLINE) $(CC_FLAGS_CHECK_STACK)
+CFLAGS_REMOVE_getcpu.o = $(VDSO_CFLAGS_REMOVE)
+CFLAGS_REMOVE_vdso64_generic.o = $(VDSO_CFLAGS_REMOVE)
 
 # Build rules
 
@@ -25,7 +26,7 @@ KBUILD_AFLAGS_64 += -m64 -s
 
 KBUILD_CFLAGS_64 := $(filter-out -m64,$(KBUILD_CFLAGS))
 KBUILD_CFLAGS_64 += -m64 -fPIC -shared -fno-common -fno-builtin
-ldflags-y := -fPIC -shared -nostdlib -soname=linux-vdso64.so.1 \
+ldflags-y := -fPIC -shared -soname=linux-vdso64.so.1 \
 	     --hash-style=both --build-id=sha1 -T
 
 $(targets:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_64)

arch/x86/Kconfig

@@ -193,7 +193,7 @@ config X86
 	select HAVE_DYNAMIC_FTRACE_WITH_ARGS	if X86_64
 	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
 	select HAVE_SAMPLE_FTRACE_DIRECT	if X86_64
-	select HAVE_SAMPLE_FTRACE_MULTI_DIRECT	if X86_64
+	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI	if X86_64
 	select HAVE_EBPF_JIT
 	select HAVE_EFFICIENT_UNALIGNED_ACCESS
 	select HAVE_EISA

drivers/s390/block/dasd_devmap.c

@@ -731,7 +731,7 @@ static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
 		ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
 	else
 		ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
-	return snprintf(buf, PAGE_SIZE, ff_flag ? "1\n" : "0\n");
+	return sysfs_emit(buf, ff_flag ? "1\n" : "0\n");
 }
 
 static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
@@ -773,7 +773,7 @@ dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
 	spin_unlock(&dasd_devmap_lock);
 
 out:
-	return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
+	return sysfs_emit(buf, ro_flag ? "1\n" : "0\n");
 }
 
 static ssize_t
@@ -834,7 +834,7 @@ dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
 		erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
 	else
 		erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
-	return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
+	return sysfs_emit(buf, erplog ? "1\n" : "0\n");
 }
 
 static ssize_t
@@ -1033,13 +1033,13 @@ dasd_discipline_show(struct device *dev, struct device_attribute *attr,
 		dasd_put_device(device);
 		goto out;
 	} else {
-		len = snprintf(buf, PAGE_SIZE, "%s\n",
-			       device->discipline->name);
+		len = sysfs_emit(buf, "%s\n",
+				 device->discipline->name);
 		dasd_put_device(device);
 		return len;
 	}
 out:
-	len = snprintf(buf, PAGE_SIZE, "none\n");
+	len = sysfs_emit(buf, "none\n");
 	return len;
 }
 
@@ -1056,30 +1056,30 @@ dasd_device_status_show(struct device *dev, struct device_attribute *attr,
 	if (!IS_ERR(device)) {
 		switch (device->state) {
 		case DASD_STATE_NEW:
-			len = snprintf(buf, PAGE_SIZE, "new\n");
+			len = sysfs_emit(buf, "new\n");
 			break;
 		case DASD_STATE_KNOWN:
-			len = snprintf(buf, PAGE_SIZE, "detected\n");
+			len = sysfs_emit(buf, "detected\n");
 			break;
 		case DASD_STATE_BASIC:
-			len = snprintf(buf, PAGE_SIZE, "basic\n");
+			len = sysfs_emit(buf, "basic\n");
 			break;
 		case DASD_STATE_UNFMT:
-			len = snprintf(buf, PAGE_SIZE, "unformatted\n");
+			len = sysfs_emit(buf, "unformatted\n");
 			break;
 		case DASD_STATE_READY:
-			len = snprintf(buf, PAGE_SIZE, "ready\n");
+			len = sysfs_emit(buf, "ready\n");
 			break;
 		case DASD_STATE_ONLINE:
-			len = snprintf(buf, PAGE_SIZE, "online\n");
+			len = sysfs_emit(buf, "online\n");
 			break;
 		default:
-			len = snprintf(buf, PAGE_SIZE, "no stat\n");
+			len = sysfs_emit(buf, "no stat\n");
 			break;
 		}
 		dasd_put_device(device);
 	} else
-		len = snprintf(buf, PAGE_SIZE, "unknown\n");
+		len = sysfs_emit(buf, "unknown\n");
 	return len;
 }
 
@@ -1120,7 +1120,7 @@ static ssize_t dasd_vendor_show(struct device *dev,
 	device = dasd_device_from_cdev(to_ccwdev(dev));
 	vendor = "";
 	if (IS_ERR(device))
-		return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
+		return sysfs_emit(buf, "%s\n", vendor);
 
 	if (device->discipline && device->discipline->get_uid &&
 	    !device->discipline->get_uid(device, &uid))
@@ -1128,7 +1128,7 @@ static ssize_t dasd_vendor_show(struct device *dev,
 
 	dasd_put_device(device);
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
+	return sysfs_emit(buf, "%s\n", vendor);
 }
 
 static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
@@ -1148,7 +1148,7 @@ dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
 	device = dasd_device_from_cdev(to_ccwdev(dev));
 	uid_string[0] = 0;
 	if (IS_ERR(device))
-		return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
+		return sysfs_emit(buf, "%s\n", uid_string);
 
 	if (device->discipline && device->discipline->get_uid &&
 	    !device->discipline->get_uid(device, &uid)) {
@@ -1183,7 +1183,7 @@ dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
 	}
 	dasd_put_device(device);
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
+	return sysfs_emit(buf, "%s\n", uid_string);
 }
 static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
 
@@ -1201,7 +1201,7 @@ dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
 		eer_flag = dasd_eer_enabled(devmap->device);
 	else
 		eer_flag = 0;
-	return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
+	return sysfs_emit(buf, eer_flag ? "1\n" : "0\n");
 }
 
 static ssize_t
@@ -1243,7 +1243,7 @@ dasd_expires_show(struct device *dev, struct device_attribute *attr, char *buf)
 	device = dasd_device_from_cdev(to_ccwdev(dev));
 	if (IS_ERR(device))
 		return -ENODEV;
-	len = snprintf(buf, PAGE_SIZE, "%lu\n", device->default_expires);
+	len = sysfs_emit(buf, "%lu\n", device->default_expires);
 	dasd_put_device(device);
 	return len;
 }
@@ -1283,7 +1283,7 @@ dasd_retries_show(struct device *dev, struct device_attribute *attr, char *buf)
 	device = dasd_device_from_cdev(to_ccwdev(dev));
 	if (IS_ERR(device))
 		return -ENODEV;
-	len = snprintf(buf, PAGE_SIZE, "%lu\n", device->default_retries);
+	len = sysfs_emit(buf, "%lu\n", device->default_retries);
 	dasd_put_device(device);
 	return len;
 }
@@ -1324,7 +1324,7 @@ dasd_timeout_show(struct device *dev, struct device_attribute *attr,
 	device = dasd_device_from_cdev(to_ccwdev(dev));
 	if (IS_ERR(device))
 		return -ENODEV;
-	len = snprintf(buf, PAGE_SIZE, "%lu\n", device->blk_timeout);
+	len = sysfs_emit(buf, "%lu\n", device->blk_timeout);
 	dasd_put_device(device);
 	return len;
 }
@@ -1398,11 +1398,11 @@ static ssize_t dasd_hpf_show(struct device *dev, struct device_attribute *attr,
 		return -ENODEV;
 	if (!device->discipline || !device->discipline->hpf_enabled) {
 		dasd_put_device(device);
-		return snprintf(buf, PAGE_SIZE, "%d\n", dasd_nofcx);
+		return sysfs_emit(buf, "%d\n", dasd_nofcx);
 	}
 	hpf = device->discipline->hpf_enabled(device);
 	dasd_put_device(device);
-	return snprintf(buf, PAGE_SIZE, "%d\n", hpf);
+	return sysfs_emit(buf, "%d\n", hpf);
 }
 
 static DEVICE_ATTR(hpf, 0444, dasd_hpf_show, NULL);
@@ -1416,13 +1416,13 @@ static ssize_t dasd_reservation_policy_show(struct device *dev,
 
 	devmap = dasd_find_busid(dev_name(dev));
 	if (IS_ERR(devmap)) {
-		rc = snprintf(buf, PAGE_SIZE, "ignore\n");
+		rc = sysfs_emit(buf, "ignore\n");
 	} else {
 		spin_lock(&dasd_devmap_lock);
 		if (devmap->features & DASD_FEATURE_FAILONSLCK)
-			rc = snprintf(buf, PAGE_SIZE, "fail\n");
+			rc = sysfs_emit(buf, "fail\n");
 		else
-			rc = snprintf(buf, PAGE_SIZE, "ignore\n");
+			rc = sysfs_emit(buf, "ignore\n");
 		spin_unlock(&dasd_devmap_lock);
 	}
 	return rc;
@@ -1457,14 +1457,14 @@ static ssize_t dasd_reservation_state_show(struct device *dev,
 
 	device = dasd_device_from_cdev(to_ccwdev(dev));
 	if (IS_ERR(device))
-		return snprintf(buf, PAGE_SIZE, "none\n");
+		return sysfs_emit(buf, "none\n");
 
 	if (test_bit(DASD_FLAG_IS_RESERVED, &device->flags))
-		rc = snprintf(buf, PAGE_SIZE, "reserved\n");
+		rc = sysfs_emit(buf, "reserved\n");
 	else if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags))
-		rc = snprintf(buf, PAGE_SIZE, "lost\n");
+		rc = sysfs_emit(buf, "lost\n");
 	else
-		rc = snprintf(buf, PAGE_SIZE, "none\n");
+		rc = sysfs_emit(buf, "none\n");
 	dasd_put_device(device);
 	return rc;
 }
@@ -1531,7 +1531,7 @@ dasd_path_threshold_show(struct device *dev,
 	device = dasd_device_from_cdev(to_ccwdev(dev));
 	if (IS_ERR(device))
 		return -ENODEV;
-	len = snprintf(buf, PAGE_SIZE, "%lu\n", device->path_thrhld);
+	len = sysfs_emit(buf, "%lu\n", device->path_thrhld);
 	dasd_put_device(device);
 	return len;
 }
@@ -1578,7 +1578,7 @@ dasd_path_autodisable_show(struct device *dev,
 	else
 		flag = (DASD_FEATURE_DEFAULT &
 			DASD_FEATURE_PATH_AUTODISABLE) != 0;
-	return snprintf(buf, PAGE_SIZE, flag ? "1\n" : "0\n");
+	return sysfs_emit(buf, flag ? "1\n" : "0\n");
 }
 
 static ssize_t
@@ -1616,7 +1616,7 @@ dasd_path_interval_show(struct device *dev,
 	device = dasd_device_from_cdev(to_ccwdev(dev));
 	if (IS_ERR(device))
 		return -ENODEV;
-	len = snprintf(buf, PAGE_SIZE, "%lu\n", device->path_interval);
+	len = sysfs_emit(buf, "%lu\n", device->path_interval);
 	dasd_put_device(device);
 	return len;
 }
@@ -1662,9 +1662,9 @@ dasd_device_fcs_show(struct device *dev, struct device_attribute *attr,
 		return -ENODEV;
 	fc_sec = dasd_path_get_fcs_device(device);
 	if (fc_sec == -EINVAL)
-		rc = snprintf(buf, PAGE_SIZE, "Inconsistent\n");
+		rc = sysfs_emit(buf, "Inconsistent\n");
 	else
-		rc = snprintf(buf, PAGE_SIZE, "%s\n", dasd_path_get_fcs_str(fc_sec));
+		rc = sysfs_emit(buf, "%s\n", dasd_path_get_fcs_str(fc_sec));
 	dasd_put_device(device);
 
 	return rc;
@@ -1677,7 +1677,7 @@ dasd_path_fcs_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 	struct dasd_path *path = to_dasd_path(kobj);
 	unsigned int fc_sec = path->fc_security;
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", dasd_path_get_fcs_str(fc_sec));
+	return sysfs_emit(buf, "%s\n", dasd_path_get_fcs_str(fc_sec));
 }
 
 static struct kobj_attribute path_fcs_attribute =
@@ -1698,7 +1698,7 @@ static ssize_t dasd_##_name##_show(struct device *dev,			\
 		val = _func(device);					\
 	dasd_put_device(device);					\
 									\
-	return snprintf(buf, PAGE_SIZE, "%d\n", val);			\
+	return sysfs_emit(buf, "%d\n", val);			\
 }									\
 static DEVICE_ATTR(_name, 0444, dasd_##_name##_show, NULL);		\
 

drivers/s390/char/raw3270.c

@@ -1047,24 +1047,24 @@ raw3270_probe (struct ccw_device *cdev)
 static ssize_t
 raw3270_model_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%i\n",
-			((struct raw3270 *) dev_get_drvdata(dev))->model);
+	return sysfs_emit(buf, "%i\n",
+			  ((struct raw3270 *)dev_get_drvdata(dev))->model);
 }
 static DEVICE_ATTR(model, 0444, raw3270_model_show, NULL);
 
 static ssize_t
 raw3270_rows_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%i\n",
-			((struct raw3270 *) dev_get_drvdata(dev))->rows);
+	return sysfs_emit(buf, "%i\n",
+			  ((struct raw3270 *)dev_get_drvdata(dev))->rows);
 }
 static DEVICE_ATTR(rows, 0444, raw3270_rows_show, NULL);
 
 static ssize_t
 raw3270_columns_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%i\n",
-			((struct raw3270 *) dev_get_drvdata(dev))->cols);
+	return sysfs_emit(buf, "%i\n",
+			  ((struct raw3270 *)dev_get_drvdata(dev))->cols);
 }
 static DEVICE_ATTR(columns, 0444, raw3270_columns_show, NULL);
 

drivers/s390/cio/chp.c

@@ -285,7 +285,7 @@ static ssize_t chp_configure_show(struct device *dev,
 	if (status < 0)
 		return status;
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", status);
+	return sysfs_emit(buf, "%d\n", status);
 }
 
 static int cfg_wait_idle(void);

samples/Kconfig

@@ -31,6 +31,15 @@ config SAMPLE_FTRACE_DIRECT
 	  This builds an ftrace direct function example
 	  that hooks to wake_up_process and prints the parameters.
 
+config SAMPLE_FTRACE_DIRECT_MULTI
+	tristate "Build register_ftrace_direct_multi() example"
+	depends on DYNAMIC_FTRACE_WITH_DIRECT_CALLS && m
+	depends on HAVE_SAMPLE_FTRACE_DIRECT_MULTI
+	help
+	  This builds an ftrace direct function example
+	  that hooks to wake_up_process and schedule, and prints
+	  the function addresses.
+
 config SAMPLE_TRACE_ARRAY
         tristate "Build sample module for kernel access to Ftrace instancess"
 	depends on EVENT_TRACING && m
@@ -237,5 +246,5 @@ endif # SAMPLES
 config HAVE_SAMPLE_FTRACE_DIRECT
 	bool
 
-config HAVE_SAMPLE_FTRACE_MULTI_DIRECT
+config HAVE_SAMPLE_FTRACE_DIRECT_MULTI
 	bool

samples/Makefile

@@ -22,7 +22,7 @@ subdir-$(CONFIG_SAMPLE_TIMER)		+= timers
 obj-$(CONFIG_SAMPLE_TRACE_EVENTS)	+= trace_events/
 obj-$(CONFIG_SAMPLE_TRACE_PRINTK)	+= trace_printk/
 obj-$(CONFIG_SAMPLE_FTRACE_DIRECT)	+= ftrace/
-obj-$(CONFIG_SAMPLE_FTRACE_MULTI_DIRECT) += ftrace/
+obj-$(CONFIG_SAMPLE_FTRACE_DIRECT_MULTI) += ftrace/
 obj-$(CONFIG_SAMPLE_TRACE_ARRAY)	+= ftrace/
 subdir-$(CONFIG_SAMPLE_UHID)		+= uhid
 obj-$(CONFIG_VIDEO_PCI_SKELETON)	+= v4l/

samples/ftrace/Makefile

@@ -3,7 +3,7 @@
 obj-$(CONFIG_SAMPLE_FTRACE_DIRECT) += ftrace-direct.o
 obj-$(CONFIG_SAMPLE_FTRACE_DIRECT) += ftrace-direct-too.o
 obj-$(CONFIG_SAMPLE_FTRACE_DIRECT) += ftrace-direct-modify.o
-obj-$(CONFIG_SAMPLE_FTRACE_MULTI_DIRECT) += ftrace-direct-multi.o
+obj-$(CONFIG_SAMPLE_FTRACE_DIRECT_MULTI) += ftrace-direct-multi.o
 
 CFLAGS_sample-trace-array.o := -I$(src)
 obj-$(CONFIG_SAMPLE_TRACE_ARRAY) += sample-trace-array.o

samples/ftrace/ftrace-direct-multi.c

@@ -4,6 +4,7 @@
 #include <linux/mm.h> /* for handle_mm_fault() */
 #include <linux/ftrace.h>
 #include <linux/sched/stat.h>
+#include <asm/asm-offsets.h>
 
 extern void my_direct_func(unsigned long ip);
 
@@ -14,6 +15,8 @@ void my_direct_func(unsigned long ip)
 
 extern void my_tramp(void *);
 
+#ifdef CONFIG_X86_64
+
 asm (
 "	.pushsection    .text, \"ax\", @progbits\n"
 "	.type		my_tramp, @function\n"
@@ -31,6 +34,33 @@ asm (
 "	.popsection\n"
 );
 
+#endif /* CONFIG_X86_64 */
+
+#ifdef CONFIG_S390
+
+asm (
+"	.pushsection	.text, \"ax\", @progbits\n"
+"	.type		my_tramp, @function\n"
+"	.globl		my_tramp\n"
+"   my_tramp:"
+"	lgr		%r1,%r15\n"
+"	stmg		%r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n"
+"	stg		%r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n"
+"	aghi		%r15,"__stringify(-STACK_FRAME_OVERHEAD)"\n"
+"	stg		%r1,"__stringify(__SF_BACKCHAIN)"(%r15)\n"
+"	lgr		%r2,%r0\n"
+"	brasl		%r14,my_direct_func\n"
+"	aghi		%r15,"__stringify(STACK_FRAME_OVERHEAD)"\n"
+"	lmg		%r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n"
+"	lg		%r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n"
+"	lgr		%r1,%r0\n"
+"	br		%r1\n"
+"	.size		my_tramp, .-my_tramp\n"
+"	.popsection\n"
+);
+
+#endif /* CONFIG_S390 */
+
 static struct ftrace_ops direct;
 
 static int __init ftrace_direct_multi_init(void)