v4.19.13 snapshot.
diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c
new file mode 100644
index 0000000..8b49cce
--- /dev/null
+++ b/arch/sh/kernel/traps.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bug.h>
+#include <linux/io.h>
+#include <linux/types.h>
+#include <linux/kdebug.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task_stack.h>
+#include <linux/uaccess.h>
+#include <linux/hardirq.h>
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/sched/signal.h>
+
+#include <linux/extable.h>
+#include <linux/module.h> /* print_modules */
+#include <asm/unwinder.h>
+#include <asm/traps.h>
+
+static DEFINE_SPINLOCK(die_lock);
+
+void die(const char *str, struct pt_regs *regs, long err)
+{
+ static int die_counter;
+
+ oops_enter();
+
+ spin_lock_irq(&die_lock);
+ console_verbose();
+ bust_spinlocks(1);
+
+ printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
+ print_modules();
+ show_regs(regs);
+
+ printk("Process: %s (pid: %d, stack limit = %p)\n", current->comm,
+ task_pid_nr(current), task_stack_page(current) + 1);
+
+ if (!user_mode(regs) || in_interrupt())
+ dump_mem("Stack: ", regs->regs[15], THREAD_SIZE +
+ (unsigned long)task_stack_page(current));
+
+ notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV);
+
+ bust_spinlocks(0);
+ add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
+ spin_unlock_irq(&die_lock);
+ oops_exit();
+
+ if (kexec_should_crash(current))
+ crash_kexec(regs);
+
+ if (in_interrupt())
+ panic("Fatal exception in interrupt");
+
+ if (panic_on_oops)
+ panic("Fatal exception");
+
+ do_exit(SIGSEGV);
+}
+
+void die_if_kernel(const char *str, struct pt_regs *regs, long err)
+{
+ if (!user_mode(regs))
+ die(str, regs, err);
+}
+
+/*
+ * try and fix up kernelspace address errors
+ * - userspace errors just cause EFAULT to be returned, resulting in SEGV
+ * - kernel/userspace interfaces cause a jump to an appropriate handler
+ * - other kernel errors are bad
+ */
+void die_if_no_fixup(const char *str, struct pt_regs *regs, long err)
+{
+ if (!user_mode(regs)) {
+ const struct exception_table_entry *fixup;
+ fixup = search_exception_tables(regs->pc);
+ if (fixup) {
+ regs->pc = fixup->fixup;
+ return;
+ }
+
+ die(str, regs, err);
+ }
+}
+
+#ifdef CONFIG_GENERIC_BUG
+static void handle_BUG(struct pt_regs *regs)
+{
+ const struct bug_entry *bug;
+ unsigned long bugaddr = regs->pc;
+ enum bug_trap_type tt;
+
+ if (!is_valid_bugaddr(bugaddr))
+ goto invalid;
+
+ bug = find_bug(bugaddr);
+
+ /* Switch unwinders when unwind_stack() is called */
+ if (bug->flags & BUGFLAG_UNWINDER)
+ unwinder_faulted = 1;
+
+ tt = report_bug(bugaddr, regs);
+ if (tt == BUG_TRAP_TYPE_WARN) {
+ regs->pc += instruction_size(bugaddr);
+ return;
+ }
+
+invalid:
+ die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff);
+}
+
+int is_valid_bugaddr(unsigned long addr)
+{
+ insn_size_t opcode;
+
+ if (addr < PAGE_OFFSET)
+ return 0;
+ if (probe_kernel_address((insn_size_t *)addr, opcode))
+ return 0;
+ if (opcode == TRAPA_BUG_OPCODE)
+ return 1;
+
+ return 0;
+}
+#endif
+
+/*
+ * Generic trap handler.
+ */
+BUILD_TRAP_HANDLER(debug)
+{
+ TRAP_HANDLER_DECL;
+
+ /* Rewind */
+ regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
+
+ if (notify_die(DIE_TRAP, "debug trap", regs, 0, vec & 0xff,
+ SIGTRAP) == NOTIFY_STOP)
+ return;
+
+ force_sig(SIGTRAP, current);
+}
+
+/*
+ * Special handler for BUG() traps.
+ */
+BUILD_TRAP_HANDLER(bug)
+{
+ TRAP_HANDLER_DECL;
+
+ /* Rewind */
+ regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
+
+ if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
+ SIGTRAP) == NOTIFY_STOP)
+ return;
+
+#ifdef CONFIG_GENERIC_BUG
+ if (__kernel_text_address(instruction_pointer(regs))) {
+ insn_size_t insn = *(insn_size_t *)instruction_pointer(regs);
+ if (insn == TRAPA_BUG_OPCODE)
+ handle_BUG(regs);
+ return;
+ }
+#endif
+
+ force_sig(SIGTRAP, current);
+}
+
+BUILD_TRAP_HANDLER(nmi)
+{
+ unsigned int cpu = smp_processor_id();
+ TRAP_HANDLER_DECL;
+
+ nmi_enter();
+ nmi_count(cpu)++;
+
+ switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) {
+ case NOTIFY_OK:
+ case NOTIFY_STOP:
+ break;
+ case NOTIFY_BAD:
+ die("Fatal Non-Maskable Interrupt", regs, SIGINT);
+ default:
+ printk(KERN_ALERT "Got NMI, but nobody cared. Ignoring...\n");
+ break;
+ }
+
+ nmi_exit();
+}