1 files changed, 32 insertions, 61 deletions

diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index f0cf20d4b3c5..c450120b4474 100644
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -9,11 +9,11 @@
 
 #define pr_fmt(fmt) "kprobes: " fmt
 
-#include <linux/moduleloader.h>
 #include <linux/kprobes.h>
 #include <linux/ptrace.h>
 #include <linux/preempt.h>
 #include <linux/stop_machine.h>
+#include <linux/cpufeature.h>
 #include <linux/kdebug.h>
 #include <linux/uaccess.h>
 #include <linux/extable.h>
@@ -21,10 +21,11 @@
 #include <linux/slab.h>
 #include <linux/hardirq.h>
 #include <linux/ftrace.h>
+#include <linux/execmem.h>
+#include <asm/text-patching.h>
 #include <asm/set_memory.h>
 #include <asm/sections.h>
 #include <asm/dis.h>
-#include "kprobes.h"
 #include "entry.h"
 
 DEFINE_PER_CPU(struct kprobe *, current_kprobe);
@@ -32,39 +33,17 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
 
 struct kretprobe_blackpoint kretprobe_blacklist[] = { };
 
-static int insn_page_in_use;
-
 void *alloc_insn_page(void)
 {
 	void *page;
 
-	page = module_alloc(PAGE_SIZE);
+	page = execmem_alloc(EXECMEM_KPROBES, PAGE_SIZE);
 	if (!page)
 		return NULL;
 	set_memory_rox((unsigned long)page, 1);
 	return page;
 }
 
-static void *alloc_s390_insn_page(void)
-{
-	if (xchg(&insn_page_in_use, 1) == 1)
-		return NULL;
-	return &kprobes_insn_page;
-}
-
-static void free_s390_insn_page(void *page)
-{
-	xchg(&insn_page_in_use, 0);
-}
-
-struct kprobe_insn_cache kprobe_s390_insn_slots = {
-	.mutex = __MUTEX_INITIALIZER(kprobe_s390_insn_slots.mutex),
-	.alloc = alloc_s390_insn_page,
-	.free = free_s390_insn_page,
-	.pages = LIST_HEAD_INIT(kprobe_s390_insn_slots.pages),
-	.insn_size = MAX_INSN_SIZE,
-};
-
 static void copy_instruction(struct kprobe *p)
 {
 	kprobe_opcode_t insn[MAX_INSN_SIZE];
@@ -78,10 +57,10 @@ static void copy_instruction(struct kprobe *p)
 	if (probe_is_insn_relative_long(&insn[0])) {
 		/*
 		 * For pc-relative instructions in RIL-b or RIL-c format patch
-		 * the RI2 displacement field. We have already made sure that
-		 * the insn slot for the patched instruction is within the same
-		 * 2GB area as the original instruction (either kernel image or
-		 * module area). Therefore the new displacement will always fit.
+		 * the RI2 displacement field. The insn slot for the to be
+		 * patched instruction is within the same 4GB area like the
+		 * original instruction. Therefore the new displacement will
+		 * always fit.
 		 */
 		disp = *(s32 *)&insn[1];
 		addr = (u64)(unsigned long)p->addr;
@@ -93,34 +72,6 @@ static void copy_instruction(struct kprobe *p)
 }
 NOKPROBE_SYMBOL(copy_instruction);
 
-static int s390_get_insn_slot(struct kprobe *p)
-{
-	/*
-	 * Get an insn slot that is within the same 2GB area like the original
-	 * instruction. That way instructions with a 32bit signed displacement
-	 * field can be patched and executed within the insn slot.
-	 */
-	p->ainsn.insn = NULL;
-	if (is_kernel((unsigned long)p->addr))
-		p->ainsn.insn = get_s390_insn_slot();
-	else if (is_module_addr(p->addr))
-		p->ainsn.insn = get_insn_slot();
-	return p->ainsn.insn ? 0 : -ENOMEM;
-}
-NOKPROBE_SYMBOL(s390_get_insn_slot);
-
-static void s390_free_insn_slot(struct kprobe *p)
-{
-	if (!p->ainsn.insn)
-		return;
-	if (is_kernel((unsigned long)p->addr))
-		free_s390_insn_slot(p->ainsn.insn, 0);
-	else
-		free_insn_slot(p->ainsn.insn, 0);
-	p->ainsn.insn = NULL;
-}
-NOKPROBE_SYMBOL(s390_free_insn_slot);
-
 /* Check if paddr is at an instruction boundary */
 static bool can_probe(unsigned long paddr)
 {
@@ -174,7 +125,8 @@ int arch_prepare_kprobe(struct kprobe *p)
 	/* Make sure the probe isn't going on a difficult instruction */
 	if (probe_is_prohibited_opcode(p->addr))
 		return -EINVAL;
-	if (s390_get_insn_slot(p))
+	p->ainsn.insn = get_insn_slot();
+	if (!p->ainsn.insn)
 		return -ENOMEM;
 	copy_instruction(p);
 	return 0;
@@ -202,7 +154,12 @@ void arch_arm_kprobe(struct kprobe *p)
 {
 	struct swap_insn_args args = {.p = p, .arm_kprobe = 1};
 
-	stop_machine_cpuslocked(swap_instruction, &args, NULL);
+	if (cpu_has_seq_insn()) {
+		swap_instruction(&args);
+		text_poke_sync();
+	} else {
+		stop_machine_cpuslocked(swap_instruction, &args, NULL);
+	}
 }
 NOKPROBE_SYMBOL(arch_arm_kprobe);
 
@@ -210,13 +167,21 @@ void arch_disarm_kprobe(struct kprobe *p)
 {
 	struct swap_insn_args args = {.p = p, .arm_kprobe = 0};
 
-	stop_machine_cpuslocked(swap_instruction, &args, NULL);
+	if (cpu_has_seq_insn()) {
+		swap_instruction(&args);
+		text_poke_sync();
+	} else {
+		stop_machine_cpuslocked(swap_instruction, &args, NULL);
+	}
 }
 NOKPROBE_SYMBOL(arch_disarm_kprobe);
 
 void arch_remove_kprobe(struct kprobe *p)
 {
-	s390_free_insn_slot(p);
+	if (!p->ainsn.insn)
+		return;
+	free_insn_slot(p->ainsn.insn, 0);
+	p->ainsn.insn = NULL;
 }
 NOKPROBE_SYMBOL(arch_remove_kprobe);
 
@@ -525,6 +490,12 @@ int __init arch_init_kprobes(void)
 	return 0;
 }
 
+int __init arch_populate_kprobe_blacklist(void)
+{
+	return kprobe_add_area_blacklist((unsigned long)__irqentry_text_start,
+					 (unsigned long)__irqentry_text_end);
+}
+
 int arch_trampoline_kprobe(struct kprobe *p)
 {
 	return 0;