Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 193 insertions, 0 deletions

diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c
new file mode 100644
index 000000000..8b49cced6
--- /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();
+}