4 files changed, 14 insertions, 91 deletions

diff --git a/arch/riscv/kernel/probes/Makefile b/arch/riscv/kernel/probes/Makefile
index 8265ff497977..d2129f2c61b8 100644
--- a/arch/riscv/kernel/probes/Makefile
+++ b/arch/riscv/kernel/probes/Makefile
@@ -1,7 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_KPROBES)		+= kprobes.o decode-insn.o simulate-insn.o
 obj-$(CONFIG_RETHOOK)		+= rethook.o rethook_trampoline.o
-obj-$(CONFIG_KPROBES_ON_FTRACE)	+= ftrace.o
 obj-$(CONFIG_UPROBES)		+= uprobes.o decode-insn.o simulate-insn.o
 CFLAGS_REMOVE_simulate-insn.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_rethook.o = $(CC_FLAGS_FTRACE)
diff --git a/arch/riscv/kernel/probes/ftrace.c b/arch/riscv/kernel/probes/ftrace.c
deleted file mode 100644
index 7142ec42e889..000000000000
--- a/arch/riscv/kernel/probes/ftrace.c
+++ /dev/null
@@ -1,62 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-#include <linux/kprobes.h>
-
-/* Ftrace callback handler for kprobes -- called under preepmt disabled */
-void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
-			   struct ftrace_ops *ops, struct ftrace_regs *fregs)
-{
-	struct kprobe *p;
-	struct pt_regs *regs;
-	struct kprobe_ctlblk *kcb;
-	int bit;
-
-	bit = ftrace_test_recursion_trylock(ip, parent_ip);
-	if (bit < 0)
-		return;
-
-	p = get_kprobe((kprobe_opcode_t *)ip);
-	if (unlikely(!p) || kprobe_disabled(p))
-		goto out;
-
-	regs = ftrace_get_regs(fregs);
-	kcb = get_kprobe_ctlblk();
-	if (kprobe_running()) {
-		kprobes_inc_nmissed_count(p);
-	} else {
-		unsigned long orig_ip = instruction_pointer(regs);
-
-		instruction_pointer_set(regs, ip);
-
-		__this_cpu_write(current_kprobe, p);
-		kcb->kprobe_status = KPROBE_HIT_ACTIVE;
-		if (!p->pre_handler || !p->pre_handler(p, regs)) {
-			/*
-			 * Emulate singlestep (and also recover regs->pc)
-			 * as if there is a nop
-			 */
-			instruction_pointer_set(regs,
-				(unsigned long)p->addr + MCOUNT_INSN_SIZE);
-			if (unlikely(p->post_handler)) {
-				kcb->kprobe_status = KPROBE_HIT_SSDONE;
-				p->post_handler(p, regs, 0);
-			}
-			instruction_pointer_set(regs, orig_ip);
-		}
-
-		/*
-		 * If pre_handler returns !0, it changes regs->pc. We have to
-		 * skip emulating post_handler.
-		 */
-		__this_cpu_write(current_kprobe, NULL);
-	}
-out:
-	ftrace_test_recursion_unlock(bit);
-}
-NOKPROBE_SYMBOL(kprobe_ftrace_handler);
-
-int arch_prepare_kprobe_ftrace(struct kprobe *p)
-{
-	p->ainsn.api.insn = NULL;
-	return 0;
-}
diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c
index 2f08c14a933d..c0738d6c6498 100644
--- a/arch/riscv/kernel/probes/kprobes.c
+++ b/arch/riscv/kernel/probes/kprobes.c
@@ -6,12 +6,13 @@
 #include <linux/extable.h>
 #include <linux/slab.h>
 #include <linux/stop_machine.h>
+#include <linux/vmalloc.h>
 #include <asm/ptrace.h>
 #include <linux/uaccess.h>
 #include <asm/sections.h>
 #include <asm/cacheflush.h>
 #include <asm/bug.h>
-#include <asm/patch.h>
+#include <asm/text-patching.h>
 
 #include "decode-insn.h"
 
@@ -23,14 +24,13 @@ post_kprobe_handler(struct kprobe *, struct kprobe_ctlblk *, struct pt_regs *);
 
 static void __kprobes arch_prepare_ss_slot(struct kprobe *p)
 {
+	size_t len = GET_INSN_LENGTH(p->opcode);
 	u32 insn = __BUG_INSN_32;
-	unsigned long offset = GET_INSN_LENGTH(p->opcode);
 
-	p->ainsn.api.restore = (unsigned long)p->addr + offset;
+	p->ainsn.api.restore = (unsigned long)p->addr + len;
 
-	patch_text(p->ainsn.api.insn, &p->opcode, 1);
-	patch_text((void *)((unsigned long)(p->ainsn.api.insn) + offset),
-		   &insn, 1);
+	patch_text_nosync(p->ainsn.api.insn, &p->opcode, len);
+	patch_text_nosync((void *)p->ainsn.api.insn + len, &insn, GET_INSN_LENGTH(insn));
 }
 
 static void __kprobes arch_prepare_simulate(struct kprobe *p)
@@ -104,29 +104,21 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
 	return 0;
 }
 
-#ifdef CONFIG_MMU
-void *alloc_insn_page(void)
-{
-	return  __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, VMALLOC_END,
-				     GFP_KERNEL, PAGE_KERNEL_READ_EXEC,
-				     VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
-				     __builtin_return_address(0));
-}
-#endif
-
 /* install breakpoint in text */
 void __kprobes arch_arm_kprobe(struct kprobe *p)
 {
-	u32 insn = (p->opcode & __INSN_LENGTH_MASK) == __INSN_LENGTH_32 ?
-		   __BUG_INSN_32 : __BUG_INSN_16;
+	size_t len = GET_INSN_LENGTH(p->opcode);
+	u32 insn = len == 4 ? __BUG_INSN_32 : __BUG_INSN_16;
 
-	patch_text(p->addr, &insn, 1);
+	patch_text(p->addr, &insn, len);
 }
 
 /* remove breakpoint from text */
 void __kprobes arch_disarm_kprobe(struct kprobe *p)
 {
-	patch_text(p->addr, &p->opcode, 1);
+	size_t len = GET_INSN_LENGTH(p->opcode);
+
+	patch_text(p->addr, &p->opcode, len);
 }
 
 void __kprobes arch_remove_kprobe(struct kprobe *p)
diff --git a/arch/riscv/kernel/probes/uprobes.c b/arch/riscv/kernel/probes/uprobes.c
index 4b3dc8beaf77..cc15f7ca6cc1 100644
--- a/arch/riscv/kernel/probes/uprobes.c
+++ b/arch/riscv/kernel/probes/uprobes.c
@@ -167,6 +167,7 @@ void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,
 	/* Initialize the slot */
 	void *kaddr = kmap_atomic(page);
 	void *dst = kaddr + (vaddr & ~PAGE_MASK);
+	unsigned long start = (unsigned long)dst;
 
 	memcpy(dst, src, len);
 
@@ -176,13 +177,6 @@ void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,
 		*(uprobe_opcode_t *)dst = __BUG_INSN_32;
 	}
 
+	flush_icache_range(start, start + len);
 	kunmap_atomic(kaddr);
-
-	/*
-	 * We probably need flush_icache_user_page() but it needs vma.
-	 * This should work on most of architectures by default. If
-	 * architecture needs to do something different it can define
-	 * its own version of the function.
-	 */
-	flush_dcache_page(page);
 }