diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index f53ef1ac3122..4df6bd7d01ed 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2402,6 +2402,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
 	noalign		[KNL,ARM]
 
+	noaltinstr	[S390] Disables alternative instructions patching
+			(CPU alternatives feature).
+
 	noapic		[SMP,APIC] Tells the kernel to not make use of any
 			IOAPICs that may be present in the system.
 
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 2ee95ece0498..89eb54f9f7d6 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -705,6 +705,22 @@ config SECCOMP
 
 	  If unsure, say Y.
 
+config ALTERNATIVES
+	def_bool y
+	prompt "Patch optimized instructions for running CPU type"
+	help
+	  When enabled the kernel code is compiled with additional
+	  alternative instructions blocks optimized for newer CPU types.
+	  These alternative instructions blocks are patched at kernel boot
+	  time when running CPU supports them. This mechanism is used to
+	  optimize some critical code paths (i.e. spinlocks) for newer CPUs
+	  even if kernel is build to support older machine generations.
+
+	  This mechanism could be disabled by appending "noaltinstr"
+	  option to the kernel command line.
+
+	  If unsure, say Y.
+
 endmenu
 
 menu "Power Management"
@@ -754,6 +770,7 @@ config PFAULT
 config SHARED_KERNEL
 	bool "VM shared kernel support"
 	depends on !JUMP_LABEL
+	depends on !ALTERNATIVES
 	help
 	  Select this option, if you want to share the text segment of the
 	  Linux kernel between different VM guests. This reduces memory
diff --git a/arch/s390/include/asm/alternative.h b/arch/s390/include/asm/alternative.h
new file mode 100644
index 000000000000..6c268f6a51d3
--- /dev/null
+++ b/arch/s390/include/asm/alternative.h
@@ -0,0 +1,163 @@
+#ifndef _ASM_S390_ALTERNATIVE_H
+#define _ASM_S390_ALTERNATIVE_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/stringify.h>
+
+struct alt_instr {
+	s32 instr_offset;	/* original instruction */
+	s32 repl_offset;	/* offset to replacement instruction */
+	u16 facility;		/* facility bit set for replacement */
+	u8  instrlen;		/* length of original instruction */
+	u8  replacementlen;	/* length of new instruction */
+} __packed;
+
+#ifdef CONFIG_ALTERNATIVES
+extern void apply_alternative_instructions(void);
+extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end);
+#else
+static inline void apply_alternative_instructions(void) {};
+static inline void apply_alternatives(struct alt_instr *start,
+				      struct alt_instr *end) {};
+#endif
+/*
+ * |661:       |662:	  |6620      |663:
+ * +-----------+---------------------+
+ * | oldinstr  | oldinstr_padding    |
+ * |	       +----------+----------+
+ * |	       |	  |	     |
+ * |	       | >6 bytes |6/4/2 nops|
+ * |	       |6 bytes jg----------->
+ * +-----------+---------------------+
+ *		 ^^ static padding ^^
+ *
+ * .altinstr_replacement section
+ * +---------------------+-----------+
+ * |6641:			     |6651:
+ * | alternative instr 1	     |
+ * +-----------+---------+- - - - - -+
+ * |6642:		 |6652:      |
+ * | alternative instr 2 | padding
+ * +---------------------+- - - - - -+
+ *			  ^ runtime ^
+ *
+ * .altinstructions section
+ * +---------------------------------+
+ * | alt_instr entries for each      |
+ * | alternative instr		     |
+ * +---------------------------------+
+ */
+
+#define b_altinstr(num)	"664"#num
+#define e_altinstr(num)	"665"#num
+
+#define e_oldinstr_pad_end	"663"
+#define oldinstr_len		"662b-661b"
+#define oldinstr_total_len	e_oldinstr_pad_end"b-661b"
+#define altinstr_len(num)	e_altinstr(num)"b-"b_altinstr(num)"b"
+#define oldinstr_pad_len(num) \
+	"-(((" altinstr_len(num) ")-(" oldinstr_len ")) > 0) * " \
+	"((" altinstr_len(num) ")-(" oldinstr_len "))"
+
+#define INSTR_LEN_SANITY_CHECK(len)					\
+	".if " len " > 254\n"						\
+	"\t.error \"cpu alternatives does not support instructions "	\
+		"blocks > 254 bytes\"\n"				\
+	".endif\n"							\
+	".if (" len ") %% 2\n"						\
+	"\t.error \"cpu alternatives instructions length is odd\"\n"	\
+	".endif\n"
+
+#define OLDINSTR_PADDING(oldinstr, num)					\
+	".if " oldinstr_pad_len(num) " > 6\n"				\
+	"\tjg " e_oldinstr_pad_end "f\n"				\
+	"6620:\n"							\
+	"\t.fill (" oldinstr_pad_len(num) " - (6620b-662b)) / 2, 2, 0x0700\n" \
+	".else\n"							\
+	"\t.fill " oldinstr_pad_len(num) " / 6, 6, 0xc0040000\n"	\
+	"\t.fill " oldinstr_pad_len(num) " %% 6 / 4, 4, 0x47000000\n"	\
+	"\t.fill " oldinstr_pad_len(num) " %% 6 %% 4 / 2, 2, 0x0700\n"	\
+	".endif\n"
+
+#define OLDINSTR(oldinstr, num)						\
+	"661:\n\t" oldinstr "\n662:\n"					\
+	OLDINSTR_PADDING(oldinstr, num)					\
+	e_oldinstr_pad_end ":\n"					\
+	INSTR_LEN_SANITY_CHECK(oldinstr_len)
+
+#define OLDINSTR_2(oldinstr, num1, num2)				\
+	"661:\n\t" oldinstr "\n662:\n"					\
+	".if " altinstr_len(num1) " < " altinstr_len(num2) "\n"		\
+	OLDINSTR_PADDING(oldinstr, num2)				\
+	".else\n"							\
+	OLDINSTR_PADDING(oldinstr, num1)				\
+	".endif\n"							\
+	e_oldinstr_pad_end ":\n"					\
+	INSTR_LEN_SANITY_CHECK(oldinstr_len)
+
+#define ALTINSTR_ENTRY(facility, num)					\
+	"\t.long 661b - .\n"			/* old instruction */	\
+	"\t.long " b_altinstr(num)"b - .\n"	/* alt instruction */	\
+	"\t.word " __stringify(facility) "\n"	/* facility bit    */	\
+	"\t.byte " oldinstr_total_len "\n"	/* source len	   */	\
+	"\t.byte " altinstr_len(num) "\n"	/* alt instruction len */
+
+#define ALTINSTR_REPLACEMENT(altinstr, num)	/* replacement */	\
+	b_altinstr(num)":\n\t" altinstr "\n" e_altinstr(num) ":\n"	\
+	INSTR_LEN_SANITY_CHECK(altinstr_len(num))
+
+#ifdef CONFIG_ALTERNATIVES
+/* alternative assembly primitive: */
+#define ALTERNATIVE(oldinstr, altinstr, facility) \
+	".pushsection .altinstr_replacement, \"ax\"\n"			\
+	ALTINSTR_REPLACEMENT(altinstr, 1)				\
+	".popsection\n"							\
+	OLDINSTR(oldinstr, 1)						\
+	".pushsection .altinstructions,\"a\"\n"				\
+	ALTINSTR_ENTRY(facility, 1)					\
+	".popsection\n"
+
+#define ALTERNATIVE_2(oldinstr, altinstr1, facility1, altinstr2, facility2)\
+	".pushsection .altinstr_replacement, \"ax\"\n"			\
+	ALTINSTR_REPLACEMENT(altinstr1, 1)				\
+	ALTINSTR_REPLACEMENT(altinstr2, 2)				\
+	".popsection\n"							\
+	OLDINSTR_2(oldinstr, 1, 2)					\
+	".pushsection .altinstructions,\"a\"\n"				\
+	ALTINSTR_ENTRY(facility1, 1)					\
+	ALTINSTR_ENTRY(facility2, 2)					\
+	".popsection\n"
+#else
+/* Alternative instructions are disabled, let's put just oldinstr in */
+#define ALTERNATIVE(oldinstr, altinstr, facility) \
+	oldinstr "\n"
+
+#define ALTERNATIVE_2(oldinstr, altinstr1, facility1, altinstr2, facility2) \
+	oldinstr "\n"
+#endif
+
+/*
+ * Alternative instructions for different CPU types or capabilities.
+ *
+ * This allows to use optimized instructions even on generic binary
+ * kernels.
+ *
+ * oldinstr is padded with jump and nops at compile time if altinstr is
+ * longer. altinstr is padded with jump and nops at run-time during patching.
+ *
+ * For non barrier like inlines please define new variants
+ * without volatile and memory clobber.
+ */
+#define alternative(oldinstr, altinstr, facility)			\
+	asm volatile(ALTERNATIVE(oldinstr, altinstr, facility) : : : "memory")
+
+#define alternative_2(oldinstr, altinstr1, facility1, altinstr2, facility2) \
+	asm volatile(ALTERNATIVE_2(oldinstr, altinstr1, facility1,	    \
+				   altinstr2, facility2) ::: "memory")
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_S390_ALTERNATIVE_H */
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index dc167a23b920..c1a0075e1384 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_KPROBES)		+= kprobes.o
 obj-$(CONFIG_FUNCTION_TRACER)	+= mcount.o ftrace.o
 obj-$(CONFIG_CRASH_DUMP)	+= crash_dump.o
 obj-$(CONFIG_UPROBES)		+= uprobes.o
+obj-$(CONFIG_ALTERNATIVES)	+= alternative.o
 
 obj-$(CONFIG_PERF_EVENTS)	+= perf_event.o perf_cpum_cf.o perf_cpum_sf.o
 obj-$(CONFIG_PERF_EVENTS)	+= perf_cpum_cf_events.o
diff --git a/arch/s390/kernel/alternative.c b/arch/s390/kernel/alternative.c
new file mode 100644
index 000000000000..315986a06cf5
--- /dev/null
+++ b/arch/s390/kernel/alternative.c
@@ -0,0 +1,110 @@
+#include <linux/module.h>
+#include <asm/alternative.h>
+#include <asm/facility.h>
+
+#define MAX_PATCH_LEN (255 - 1)
+
+static int __initdata_or_module alt_instr_disabled;
+
+static int __init disable_alternative_instructions(char *str)
+{
+	alt_instr_disabled = 1;
+	return 0;
+}
+
+early_param("noaltinstr", disable_alternative_instructions);
+
+struct brcl_insn {
+	u16 opc;
+	s32 disp;
+} __packed;
+
+static u16 __initdata_or_module nop16 = 0x0700;
+static u32 __initdata_or_module nop32 = 0x47000000;
+static struct brcl_insn __initdata_or_module nop48 = {
+	0xc004, 0
+};
+
+static const void *nops[] __initdata_or_module = {
+	&nop16,
+	&nop32,
+	&nop48
+};
+
+static void __init_or_module add_jump_padding(void *insns, unsigned int len)
+{
+	struct brcl_insn brcl = {
+		0xc0f4,
+		len / 2
+	};
+
+	memcpy(insns, &brcl, sizeof(brcl));
+	insns += sizeof(brcl);
+	len -= sizeof(brcl);
+
+	while (len > 0) {
+		memcpy(insns, &nop16, 2);
+		insns += 2;
+		len -= 2;
+	}
+}
+
+static void __init_or_module add_padding(void *insns, unsigned int len)
+{
+	if (len > 6)
+		add_jump_padding(insns, len);
+	else if (len >= 2)
+		memcpy(insns, nops[len / 2 - 1], len);
+}
+
+static void __init_or_module __apply_alternatives(struct alt_instr *start,
+						  struct alt_instr *end)
+{
+	struct alt_instr *a;
+	u8 *instr, *replacement;
+	u8 insnbuf[MAX_PATCH_LEN];
+
+	/*
+	 * The scan order should be from start to end. A later scanned
+	 * alternative code can overwrite previously scanned alternative code.
+	 */
+	for (a = start; a < end; a++) {
+		int insnbuf_sz = 0;
+
+		instr = (u8 *)&a->instr_offset + a->instr_offset;
+		replacement = (u8 *)&a->repl_offset + a->repl_offset;
+
+		if (!test_facility(a->facility))
+			continue;
+
+		if (unlikely(a->instrlen % 2 || a->replacementlen % 2)) {
+			WARN_ONCE(1, "cpu alternatives instructions length is "
+				     "odd, skipping patching\n");
+			continue;
+		}
+
+		memcpy(insnbuf, replacement, a->replacementlen);
+		insnbuf_sz = a->replacementlen;
+
+		if (a->instrlen > a->replacementlen) {
+			add_padding(insnbuf + a->replacementlen,
+				    a->instrlen - a->replacementlen);
+			insnbuf_sz += a->instrlen - a->replacementlen;
+		}
+
+		s390_kernel_write(instr, insnbuf, insnbuf_sz);
+	}
+}
+
+void __init_or_module apply_alternatives(struct alt_instr *start,
+					 struct alt_instr *end)
+{
+	if (!alt_instr_disabled)
+		__apply_alternatives(start, end);
+}
+
+extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
+void __init apply_alternative_instructions(void)
+{
+	apply_alternatives(__alt_instructions, __alt_instructions_end);
+}
diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c
index 0c1a679314dd..85c1ba09eae0 100644
--- a/arch/s390/kernel/module.c
+++ b/arch/s390/kernel/module.c
@@ -31,6 +31,7 @@
 #include <linux/kernel.h>
 #include <linux/moduleloader.h>
 #include <linux/bug.h>
+#include <asm/alternative.h>
 
 #if 0
 #define DEBUGP printk
@@ -424,6 +425,22 @@ int module_finalize(const Elf_Ehdr *hdr,
 		    const Elf_Shdr *sechdrs,
 		    struct module *me)
 {
+	const Elf_Shdr *s;
+	char *secstrings;
+
+	if (IS_ENABLED(CONFIG_ALTERNATIVES)) {
+		secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+		for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
+			if (!strcmp(".altinstructions",
+				    secstrings + s->sh_name)) {
+				/* patch .altinstructions */
+				void *aseg = (void *)s->sh_addr;
+
+				apply_alternatives(aseg, aseg + s->sh_size);
+			}
+		}
+	}
+
 	jump_label_apply_nops(me);
 	vfree(me->arch.syminfo);
 	me->arch.syminfo = NULL;
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index d097d71685df..136caf3128f0 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -63,6 +63,7 @@
 #include <asm/sclp.h>
 #include <asm/sysinfo.h>
 #include <asm/numa.h>
+#include <asm/alternative.h>
 #include "entry.h"
 
 /*
@@ -893,6 +894,8 @@ void __init setup_arch(char **cmdline_p)
 	conmode_default();
 	set_preferred_console();
 
+	apply_alternative_instructions();
+
 	/* Setup zfcpdump support */
 	setup_zfcpdump();
 
diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index 6c553f6e791a..6cff68a84bb3 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -78,6 +78,29 @@ SECTIONS
 		EXIT_DATA
 	}
 
+	/*
+	 * struct alt_inst entries. From the header (alternative.h):
+	 * "Alternative instructions for different CPU types or capabilities"
+	 * Think locking instructions on spinlocks.
+	 * Note, that it is a part of __init region.
+	 */
+	. = ALIGN(8);
+	.altinstructions : {
+		__alt_instructions = .;
+		*(.altinstructions)
+		__alt_instructions_end = .;
+	}
+
+	/*
+	 * And here are the replacement instructions. The linker sticks
+	 * them as binary blobs. The .altinstructions has enough data to
+	 * get the address and the length of them to patch the kernel safely.
+	 * Note, that it is a part of __init region.
+	 */
+	.altinstr_replacement : {
+		*(.altinstr_replacement)
+	}
+
 	/* early.c uses stsi, which requires page aligned data. */
 	. = ALIGN(PAGE_SIZE);
 	INIT_DATA_SECTION(0x100)