v4.19.13 snapshot.
diff --git a/arch/sh/kernel/ptrace_64.c b/arch/sh/kernel/ptrace_64.c
new file mode 100644
index 0000000..1e0656d
--- /dev/null
+++ b/arch/sh/kernel/ptrace_64.c
@@ -0,0 +1,579 @@
+/*
+ * arch/sh/kernel/ptrace_64.c
+ *
+ * Copyright (C) 2000, 2001  Paolo Alberelli
+ * Copyright (C) 2003 - 2008  Paul Mundt
+ *
+ * Started from SH3/4 version:
+ *   SuperH version:   Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka
+ *
+ *   Original x86 implementation:
+ *	By Ross Biro 1/23/92
+ *	edited by Linus Torvalds
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/signal.h>
+#include <linux/syscalls.h>
+#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/tracehook.h>
+#include <linux/elf.h>
+#include <linux/regset.h>
+#include <asm/io.h>
+#include <linux/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/mmu_context.h>
+#include <asm/syscalls.h>
+#include <asm/fpu.h>
+#include <asm/traps.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
+/* This mask defines the bits of the SR which the user is not allowed to
+   change, which are everything except S, Q, M, PR, SZ, FR. */
+#define SR_MASK      (0xffff8cfd)
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * This routine will get a word from the user area in the process kernel stack.
+ */
+static inline int get_stack_long(struct task_struct *task, int offset)
+{
+	unsigned char *stack;
+
+	stack = (unsigned char *)(task->thread.uregs);
+	stack += offset;
+	return (*((int *)stack));
+}
+
+static inline unsigned long
+get_fpu_long(struct task_struct *task, unsigned long addr)
+{
+	unsigned long tmp;
+	struct pt_regs *regs;
+	regs = (struct pt_regs*)((unsigned char *)task + THREAD_SIZE) - 1;
+
+	if (!tsk_used_math(task)) {
+		if (addr == offsetof(struct user_fpu_struct, fpscr)) {
+			tmp = FPSCR_INIT;
+		} else {
+			tmp = 0xffffffffUL; /* matches initial value in fpu.c */
+		}
+		return tmp;
+	}
+
+	if (last_task_used_math == task) {
+		enable_fpu();
+		save_fpu(task);
+		disable_fpu();
+		last_task_used_math = 0;
+		regs->sr |= SR_FD;
+	}
+
+	tmp = ((long *)task->thread.xstate)[addr / sizeof(unsigned long)];
+	return tmp;
+}
+
+/*
+ * This routine will put a word into the user area in the process kernel stack.
+ */
+static inline int put_stack_long(struct task_struct *task, int offset,
+				 unsigned long data)
+{
+	unsigned char *stack;
+
+	stack = (unsigned char *)(task->thread.uregs);
+	stack += offset;
+	*(unsigned long *) stack = data;
+	return 0;
+}
+
+static inline int
+put_fpu_long(struct task_struct *task, unsigned long addr, unsigned long data)
+{
+	struct pt_regs *regs;
+
+	regs = (struct pt_regs*)((unsigned char *)task + THREAD_SIZE) - 1;
+
+	if (!tsk_used_math(task)) {
+		init_fpu(task);
+	} else if (last_task_used_math == task) {
+		enable_fpu();
+		save_fpu(task);
+		disable_fpu();
+		last_task_used_math = 0;
+		regs->sr |= SR_FD;
+	}
+
+	((long *)task->thread.xstate)[addr / sizeof(unsigned long)] = data;
+	return 0;
+}
+
+void user_enable_single_step(struct task_struct *child)
+{
+	struct pt_regs *regs = child->thread.uregs;
+
+	regs->sr |= SR_SSTEP;	/* auto-resetting upon exception */
+
+	set_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+void user_disable_single_step(struct task_struct *child)
+{
+	struct pt_regs *regs = child->thread.uregs;
+
+	regs->sr &= ~SR_SSTEP;
+
+	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+static int genregs_get(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       void *kbuf, void __user *ubuf)
+{
+	const struct pt_regs *regs = task_pt_regs(target);
+	int ret;
+
+	/* PC, SR, SYSCALL */
+	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+				  &regs->pc,
+				  0, 3 * sizeof(unsigned long long));
+
+	/* R1 -> R63 */
+	if (!ret)
+		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+					  regs->regs,
+					  offsetof(struct pt_regs, regs[0]),
+					  63 * sizeof(unsigned long long));
+	/* TR0 -> TR7 */
+	if (!ret)
+		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+					  regs->tregs,
+					  offsetof(struct pt_regs, tregs[0]),
+					  8 * sizeof(unsigned long long));
+
+	if (!ret)
+		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+					       sizeof(struct pt_regs), -1);
+
+	return ret;
+}
+
+static int genregs_set(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       const void *kbuf, const void __user *ubuf)
+{
+	struct pt_regs *regs = task_pt_regs(target);
+	int ret;
+
+	/* PC, SR, SYSCALL */
+	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+				 &regs->pc,
+				 0, 3 * sizeof(unsigned long long));
+
+	/* R1 -> R63 */
+	if (!ret && count > 0)
+		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+					 regs->regs,
+					 offsetof(struct pt_regs, regs[0]),
+					 63 * sizeof(unsigned long long));
+
+	/* TR0 -> TR7 */
+	if (!ret && count > 0)
+		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+					 regs->tregs,
+					 offsetof(struct pt_regs, tregs[0]),
+					 8 * sizeof(unsigned long long));
+
+	if (!ret)
+		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+						sizeof(struct pt_regs), -1);
+
+	return ret;
+}
+
+#ifdef CONFIG_SH_FPU
+int fpregs_get(struct task_struct *target,
+	       const struct user_regset *regset,
+	       unsigned int pos, unsigned int count,
+	       void *kbuf, void __user *ubuf)
+{
+	int ret;
+
+	ret = init_fpu(target);
+	if (ret)
+		return ret;
+
+	return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+				   &target->thread.xstate->hardfpu, 0, -1);
+}
+
+static int fpregs_set(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       const void *kbuf, const void __user *ubuf)
+{
+	int ret;
+
+	ret = init_fpu(target);
+	if (ret)
+		return ret;
+
+	set_stopped_child_used_math(target);
+
+	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+				  &target->thread.xstate->hardfpu, 0, -1);
+}
+
+static int fpregs_active(struct task_struct *target,
+			 const struct user_regset *regset)
+{
+	return tsk_used_math(target) ? regset->n : 0;
+}
+#endif
+
+const struct pt_regs_offset regoffset_table[] = {
+	REG_OFFSET_NAME(pc),
+	REG_OFFSET_NAME(sr),
+	REG_OFFSET_NAME(syscall_nr),
+	REGS_OFFSET_NAME(0),
+	REGS_OFFSET_NAME(1),
+	REGS_OFFSET_NAME(2),
+	REGS_OFFSET_NAME(3),
+	REGS_OFFSET_NAME(4),
+	REGS_OFFSET_NAME(5),
+	REGS_OFFSET_NAME(6),
+	REGS_OFFSET_NAME(7),
+	REGS_OFFSET_NAME(8),
+	REGS_OFFSET_NAME(9),
+	REGS_OFFSET_NAME(10),
+	REGS_OFFSET_NAME(11),
+	REGS_OFFSET_NAME(12),
+	REGS_OFFSET_NAME(13),
+	REGS_OFFSET_NAME(14),
+	REGS_OFFSET_NAME(15),
+	REGS_OFFSET_NAME(16),
+	REGS_OFFSET_NAME(17),
+	REGS_OFFSET_NAME(18),
+	REGS_OFFSET_NAME(19),
+	REGS_OFFSET_NAME(20),
+	REGS_OFFSET_NAME(21),
+	REGS_OFFSET_NAME(22),
+	REGS_OFFSET_NAME(23),
+	REGS_OFFSET_NAME(24),
+	REGS_OFFSET_NAME(25),
+	REGS_OFFSET_NAME(26),
+	REGS_OFFSET_NAME(27),
+	REGS_OFFSET_NAME(28),
+	REGS_OFFSET_NAME(29),
+	REGS_OFFSET_NAME(30),
+	REGS_OFFSET_NAME(31),
+	REGS_OFFSET_NAME(32),
+	REGS_OFFSET_NAME(33),
+	REGS_OFFSET_NAME(34),
+	REGS_OFFSET_NAME(35),
+	REGS_OFFSET_NAME(36),
+	REGS_OFFSET_NAME(37),
+	REGS_OFFSET_NAME(38),
+	REGS_OFFSET_NAME(39),
+	REGS_OFFSET_NAME(40),
+	REGS_OFFSET_NAME(41),
+	REGS_OFFSET_NAME(42),
+	REGS_OFFSET_NAME(43),
+	REGS_OFFSET_NAME(44),
+	REGS_OFFSET_NAME(45),
+	REGS_OFFSET_NAME(46),
+	REGS_OFFSET_NAME(47),
+	REGS_OFFSET_NAME(48),
+	REGS_OFFSET_NAME(49),
+	REGS_OFFSET_NAME(50),
+	REGS_OFFSET_NAME(51),
+	REGS_OFFSET_NAME(52),
+	REGS_OFFSET_NAME(53),
+	REGS_OFFSET_NAME(54),
+	REGS_OFFSET_NAME(55),
+	REGS_OFFSET_NAME(56),
+	REGS_OFFSET_NAME(57),
+	REGS_OFFSET_NAME(58),
+	REGS_OFFSET_NAME(59),
+	REGS_OFFSET_NAME(60),
+	REGS_OFFSET_NAME(61),
+	REGS_OFFSET_NAME(62),
+	REGS_OFFSET_NAME(63),
+	TREGS_OFFSET_NAME(0),
+	TREGS_OFFSET_NAME(1),
+	TREGS_OFFSET_NAME(2),
+	TREGS_OFFSET_NAME(3),
+	TREGS_OFFSET_NAME(4),
+	TREGS_OFFSET_NAME(5),
+	TREGS_OFFSET_NAME(6),
+	TREGS_OFFSET_NAME(7),
+	REG_OFFSET_END,
+};
+
+/*
+ * These are our native regset flavours.
+ */
+enum sh_regset {
+	REGSET_GENERAL,
+#ifdef CONFIG_SH_FPU
+	REGSET_FPU,
+#endif
+};
+
+static const struct user_regset sh_regsets[] = {
+	/*
+	 * Format is:
+	 *	PC, SR, SYSCALL,
+	 *	R1 --> R63,
+	 *	TR0 --> TR7,
+	 */
+	[REGSET_GENERAL] = {
+		.core_note_type	= NT_PRSTATUS,
+		.n		= ELF_NGREG,
+		.size		= sizeof(long long),
+		.align		= sizeof(long long),
+		.get		= genregs_get,
+		.set		= genregs_set,
+	},
+
+#ifdef CONFIG_SH_FPU
+	[REGSET_FPU] = {
+		.core_note_type	= NT_PRFPREG,
+		.n		= sizeof(struct user_fpu_struct) /
+				  sizeof(long long),
+		.size		= sizeof(long long),
+		.align		= sizeof(long long),
+		.get		= fpregs_get,
+		.set		= fpregs_set,
+		.active		= fpregs_active,
+	},
+#endif
+};
+
+static const struct user_regset_view user_sh64_native_view = {
+	.name		= "sh64",
+	.e_machine	= EM_SH,
+	.regsets	= sh_regsets,
+	.n		= ARRAY_SIZE(sh_regsets),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+	return &user_sh64_native_view;
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+		 unsigned long addr, unsigned long data)
+{
+	int ret;
+	unsigned long __user *datap = (unsigned long __user *) data;
+
+	switch (request) {
+	/* read the word at location addr in the USER area. */
+	case PTRACE_PEEKUSR: {
+		unsigned long tmp;
+
+		ret = -EIO;
+		if ((addr & 3) || addr < 0)
+			break;
+
+		if (addr < sizeof(struct pt_regs))
+			tmp = get_stack_long(child, addr);
+		else if ((addr >= offsetof(struct user, fpu)) &&
+			 (addr <  offsetof(struct user, u_fpvalid))) {
+			unsigned long index;
+			ret = init_fpu(child);
+			if (ret)
+				break;
+			index = addr - offsetof(struct user, fpu);
+			tmp = get_fpu_long(child, index);
+		} else if (addr == offsetof(struct user, u_fpvalid)) {
+			tmp = !!tsk_used_math(child);
+		} else {
+			break;
+		}
+		ret = put_user(tmp, datap);
+		break;
+	}
+
+	case PTRACE_POKEUSR:
+                /* write the word at location addr in the USER area. We must
+                   disallow any changes to certain SR bits or u_fpvalid, since
+                   this could crash the kernel or result in a security
+                   loophole. */
+		ret = -EIO;
+		if ((addr & 3) || addr < 0)
+			break;
+
+		if (addr < sizeof(struct pt_regs)) {
+			/* Ignore change of top 32 bits of SR */
+			if (addr == offsetof (struct pt_regs, sr)+4)
+			{
+				ret = 0;
+				break;
+			}
+			/* If lower 32 bits of SR, ignore non-user bits */
+			if (addr == offsetof (struct pt_regs, sr))
+			{
+				long cursr = get_stack_long(child, addr);
+				data &= ~(SR_MASK);
+				data |= (cursr & SR_MASK);
+			}
+			ret = put_stack_long(child, addr, data);
+		}
+		else if ((addr >= offsetof(struct user, fpu)) &&
+			 (addr <  offsetof(struct user, u_fpvalid))) {
+			unsigned long index;
+			ret = init_fpu(child);
+			if (ret)
+				break;
+			index = addr - offsetof(struct user, fpu);
+			ret = put_fpu_long(child, index, data);
+		}
+		break;
+
+	case PTRACE_GETREGS:
+		return copy_regset_to_user(child, &user_sh64_native_view,
+					   REGSET_GENERAL,
+					   0, sizeof(struct pt_regs),
+					   datap);
+	case PTRACE_SETREGS:
+		return copy_regset_from_user(child, &user_sh64_native_view,
+					     REGSET_GENERAL,
+					     0, sizeof(struct pt_regs),
+					     datap);
+#ifdef CONFIG_SH_FPU
+	case PTRACE_GETFPREGS:
+		return copy_regset_to_user(child, &user_sh64_native_view,
+					   REGSET_FPU,
+					   0, sizeof(struct user_fpu_struct),
+					   datap);
+	case PTRACE_SETFPREGS:
+		return copy_regset_from_user(child, &user_sh64_native_view,
+					     REGSET_FPU,
+					     0, sizeof(struct user_fpu_struct),
+					     datap);
+#endif
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+
+	return ret;
+}
+
+asmlinkage int sh64_ptrace(long request, long pid,
+			   unsigned long addr, unsigned long data)
+{
+#define WPC_DBRMODE 0x0d104008
+	static unsigned long first_call;
+
+	if (!test_and_set_bit(0, &first_call)) {
+		/* Set WPC.DBRMODE to 0.  This makes all debug events get
+		 * delivered through RESVEC, i.e. into the handlers in entry.S.
+		 * (If the kernel was downloaded using a remote gdb, WPC.DBRMODE
+		 * would normally be left set to 1, which makes debug events get
+		 * delivered through DBRVEC, i.e. into the remote gdb's
+		 * handlers.  This prevents ptrace getting them, and confuses
+		 * the remote gdb.) */
+		printk("DBRMODE set to 0 to permit native debugging\n");
+		poke_real_address_q(WPC_DBRMODE, 0);
+	}
+
+	return sys_ptrace(request, pid, addr, data);
+}
+
+asmlinkage long long do_syscall_trace_enter(struct pt_regs *regs)
+{
+	long long ret = 0;
+
+	secure_computing_strict(regs->regs[9]);
+
+	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+	    tracehook_report_syscall_entry(regs))
+		/*
+		 * Tracing decided this syscall should not happen.
+		 * We'll return a bogus call number to get an ENOSYS
+		 * error, but leave the original number in regs->regs[0].
+		 */
+		ret = -1LL;
+
+	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
+		trace_sys_enter(regs, regs->regs[9]);
+
+	audit_syscall_entry(regs->regs[1], regs->regs[2], regs->regs[3],
+			    regs->regs[4], regs->regs[5]);
+
+	return ret ?: regs->regs[9];
+}
+
+asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
+{
+	int step;
+
+	audit_syscall_exit(regs);
+
+	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
+		trace_sys_exit(regs, regs->regs[9]);
+
+	step = test_thread_flag(TIF_SINGLESTEP);
+	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+		tracehook_report_syscall_exit(regs, step);
+}
+
+/* Called with interrupts disabled */
+asmlinkage void do_single_step(unsigned long long vec, struct pt_regs *regs)
+{
+	/* This is called after a single step exception (DEBUGSS).
+	   There is no need to change the PC, as it is a post-execution
+	   exception, as entry.S does not do anything to the PC for DEBUGSS.
+	   We need to clear the Single Step setting in SR to avoid
+	   continually stepping. */
+	local_irq_enable();
+	regs->sr &= ~SR_SSTEP;
+	force_sig(SIGTRAP, current);
+}
+
+/* Called with interrupts disabled */
+BUILD_TRAP_HANDLER(breakpoint)
+{
+	TRAP_HANDLER_DECL;
+
+	/* We need to forward step the PC, to counteract the backstep done
+	   in signal.c. */
+	local_irq_enable();
+	force_sig(SIGTRAP, current);
+	regs->pc += 4;
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure single step bits etc are not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+	user_disable_single_step(child);
+}