4 files changed, 1 insertions, 116 deletions

diff --git a/arch/mips/include/asm/ptrace.h b/arch/mips/include/asm/ptrace.h
index c733daefd015..daf3cf244ea9 100644
--- a/arch/mips/include/asm/ptrace.h
+++ b/arch/mips/include/asm/ptrace.h
@@ -186,6 +186,4 @@ static inline void user_stack_pointer_set(struct pt_regs *regs,
 	regs->regs[29] = val;
 }
 
-#define arch_has_single_step()	(1)
-
 #endif /* _ASM_PTRACE_H */
diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h
index bd4dbb5b2900..e2c352da3877 100644
--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -35,10 +35,6 @@ struct thread_info {
 						 */
 	struct pt_regs		*regs;
 	long			syscall;	/* syscall number */
-
-	int bpt_nsaved;
-	unsigned long bpt_addr[1];		/* breakpoint handling */
-	unsigned int bpt_insn[1];
 };
 
 /*
@@ -121,7 +117,6 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_UPROBE		6	/* breakpointed or singlestepping */
 #define TIF_NOTIFY_SIGNAL	7	/* signal notifications exist */
 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
-#define TIF_SINGLESTEP		10	/* restore singlestep on return to user mode */
 #define TIF_USEDFPU		16	/* FPU was used by this task this quantum (SMP) */
 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
 #define TIF_NOHZ		19	/* in adaptive nohz mode */
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index f29141922001..db7c5be1d4a3 100644
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -45,15 +45,10 @@
 #include <linux/uaccess.h>
 #include <asm/bootinfo.h>
 #include <asm/reg.h>
-#include <asm/branch.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/syscalls.h>
 
-#include "probes-common.h"
-
-#define BREAKINST	0x0000000d
-
 /*
  * Called by kernel/ptrace.c when detaching..
  *
@@ -63,7 +58,6 @@ void ptrace_disable(struct task_struct *child)
 {
 	/* Don't load the watchpoint registers for the ex-child. */
 	clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
-	user_disable_single_step(child);
 }
 
 /*
@@ -1078,108 +1072,6 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 #endif
 }
 
-static int read_insn(struct task_struct *task, unsigned long addr, unsigned int *insn)
-{
-	int copied = access_process_vm(task, addr, insn,
-				       sizeof(unsigned int), FOLL_FORCE);
-
-	if (copied != sizeof(unsigned int)) {
-		pr_err("failed to read instruction from 0x%lx\n", addr);
-		return -EIO;
-	}
-
-	return 0;
-}
-
-static int write_insn(struct task_struct *task, unsigned long addr, unsigned int insn)
-{
-	int copied = access_process_vm(task, addr, &insn,
-				       sizeof(unsigned int), FOLL_FORCE | FOLL_WRITE);
-
-	if (copied != sizeof(unsigned int)) {
-		pr_err("failed to write instruction to 0x%lx\n", addr);
-		return -EIO;
-	}
-
-	return 0;
-}
-
-static int insn_has_delayslot(union mips_instruction insn)
-{
-	return __insn_has_delay_slot(insn);
-}
-
-static void ptrace_set_bpt(struct task_struct *child)
-{
-	union mips_instruction mips_insn = { 0 };
-	struct pt_regs *regs;
-	unsigned long pc;
-	unsigned int insn;
-	int i, ret, nsaved = 0;
-
-	regs = task_pt_regs(child);
-	pc = regs->cp0_epc;
-
-	ret = read_insn(child, pc, &insn);
-	if (ret < 0)
-		return;
-
-	if (insn_has_delayslot(mips_insn)) {
-		pr_info("executing branch insn\n");
-		ret = __compute_return_epc(regs);
-		if (ret < 0)
-			return;
-		task_thread_info(child)->bpt_addr[nsaved++] = regs->cp0_epc;
-	} else {
-		pr_info("executing normal insn\n");
-		task_thread_info(child)->bpt_addr[nsaved++] = pc + 4;
-	}
-
-	/* install breakpoints */
-	for (i = 0; i < nsaved; i++) {
-		ret = read_insn(child, task_thread_info(child)->bpt_addr[i], &insn);
-		if (ret < 0)
-			return;
-
-		task_thread_info(child)->bpt_insn[i] = insn;
-
-		ret = write_insn(child, task_thread_info(child)->bpt_addr[i], BREAKINST);
-		if (ret < 0)
-			return;
-	}
-
-	task_thread_info(child)->bpt_nsaved = nsaved;
-}
-
-static void ptrace_cancel_bpt(struct task_struct *child)
-{
-	int i, nsaved = task_thread_info(child)->bpt_nsaved;
-
-	task_thread_info(child)->bpt_nsaved = 0;
-
-	if (nsaved > 1) {
-		pr_info("%s: bogus nsaved: %d!\n", __func__, nsaved);
-		nsaved = 1;
-	}
-
-	for (i = 0; i < nsaved; i++) {
-		write_insn(child, task_thread_info(child)->bpt_addr[i],
-			  task_thread_info(child)->bpt_insn[i]);
-	}
-}
-
-void user_enable_single_step(struct task_struct *child)
-{
-	set_tsk_thread_flag(child, TIF_SINGLESTEP);
-	ptrace_set_bpt(child);
-}
-
-void user_disable_single_step(struct task_struct *child)
-{
-	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
-	ptrace_cancel_bpt(child);
-}
-
 long arch_ptrace(struct task_struct *child, long request,
 		 unsigned long addr, unsigned long data)
 {
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index 82d11d88d3a5..f1e985109da0 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -849,7 +849,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
 		ret = abi->setup_frame(vdso + abi->vdso->off_sigreturn,
 				       ksig, regs, oldset);
 
-	signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
+	signal_setup_done(ret, ksig, 0);
 }
 
 static void do_signal(struct pt_regs *regs)