sh: Generic kgdb stub support.

This migrates from the old bitrotted kgdb stub implementation and moves
to the generic stub. In the process support for SH-2/SH-2A is also added,
which the old stub never provided.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/Kconfig

@@ -27,6 +27,7 @@ config SUPERH32
 	select HAVE_FUNCTION_TRACER
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_DYNAMIC_FTRACE
+	select HAVE_ARCH_KGDB
 
 config SUPERH64
 	def_bool y if CPU_SH5

arch/sh/Kconfig.debug

@@ -98,19 +98,6 @@ config IRQSTACKS
 	  for handling hard and soft interrupts.  This can help avoid
 	  overflowing the process kernel stacks.
 
-config SH_KGDB
-	bool "Include KGDB kernel debugger"
-	select FRAME_POINTER
-	select DEBUG_INFO
-	depends on CPU_SH3 || CPU_SH4
-	help
-	  Include in-kernel hooks for kgdb, the Linux kernel source level
-	  debugger.  See <http://kgdb.sourceforge.net/> for more information.
-	  Unless you are intending to debug the kernel, say N here.
-
-menu "KGDB configuration options"
-	depends on SH_KGDB
-
 config MORE_COMPILE_OPTIONS
 	bool "Add any additional compile options"
 	help
@@ -122,62 +109,6 @@ config COMPILE_OPTIONS
 	string "Additional compile arguments"
 	depends on MORE_COMPILE_OPTIONS
 
-config KGDB_NMI
-	def_bool n
-	prompt "Enter KGDB on NMI"
-
-config SH_KGDB_CONSOLE
-	def_bool n
-	prompt "Console messages through GDB"
-	depends on !SERIAL_SH_SCI_CONSOLE && SERIAL_SH_SCI=y
-	select SERIAL_CORE_CONSOLE
-
-config KGDB_SYSRQ
-	def_bool y
-	prompt "Allow SysRq 'G' to enter KGDB"
-	depends on MAGIC_SYSRQ
-
-comment "Serial port setup"
-
-config KGDB_DEFPORT
-	int "Port number (ttySCn)"
-	default "1"
-
-config KGDB_DEFBAUD
-	int "Baud rate"
-	default "115200"
-
-choice
-	prompt "Parity"
-	depends on SH_KGDB
-	default KGDB_DEFPARITY_N
-
-config KGDB_DEFPARITY_N
-	bool "None"
-
-config KGDB_DEFPARITY_E
-	bool "Even"
-
-config KGDB_DEFPARITY_O
-	bool "Odd"
-
-endchoice
-
-choice
-	prompt "Data bits"
-	depends on SH_KGDB
-	default KGDB_DEFBITS_8
-
-config KGDB_DEFBITS_8
-	bool "8"
-
-config KGDB_DEFBITS_7
-	bool "7"
-
-endchoice
-
-endmenu
-
 if SUPERH64
 
 config SH64_SR_WATCH

arch/sh/include/asm/kgdb.h

-/*
- * May be copied or modified under the terms of the GNU General Public
- * License.  See linux/COPYING for more information.
- *
- * Based on original code by Glenn Engel, Jim Kingdon,
- * David Grothe <dave@gcom.com>, Tigran Aivazian, <tigran@sco.com> and
- * Amit S. Kale <akale@veritas.com>
- * 
- * Super-H port based on sh-stub.c (Ben Lee and Steve Chamberlain) by
- * Henry Bell <henry.bell@st.com>
- * 
- * Header file for low-level support for remote debug using GDB. 
- *
- */
-
-#ifndef __KGDB_H
-#define __KGDB_H
+#ifndef __ASM_SH_KGDB_H
+#define __ASM_SH_KGDB_H
 
+#include <asm/cacheflush.h>
 #include <asm/ptrace.h>
 
 /* Same as pt_regs but has vbr in place of syscall_nr */
@@ -30,40 +16,26 @@ struct kgdb_regs {
         unsigned long vbr;
 };
 
-/* State info */
-extern char kgdb_in_gdb_mode;
-extern int kgdb_nofault;	/* Ignore bus errors (in gdb mem access) */
-extern char in_nmi;		/* Debounce flag to prevent NMI reentry*/
+enum regnames {
+	GDB_R0, GDB_R1, GDB_R2, GDB_R3, GDB_R4, GDB_R5, GDB_R6, GDB_R7,
+	GDB_R8, GDB_R9, GDB_R10, GDB_R11, GDB_R12, GDB_R13, GDB_R14, GDB_R15,
 
-/* SCI */
-extern int kgdb_portnum;
-extern int kgdb_baud;
-extern char kgdb_parity;
-extern char kgdb_bits;
+	GDB_PC, GDB_PR, GDB_SR, GDB_GBR, GDB_MACH, GDB_MACL, GDB_VBR,
+};
 
-/* Init and interface stuff */
-extern int kgdb_init(void);
-extern int (*kgdb_getchar)(void);
-extern void (*kgdb_putchar)(int);
+#define NUMREGBYTES    ((GDB_VBR + 1) * 4)
 
-/* Trap functions */
-typedef void (kgdb_debug_hook_t)(struct pt_regs *regs);
-typedef void (kgdb_bus_error_hook_t)(void);
-extern kgdb_debug_hook_t  *kgdb_debug_hook;
-extern kgdb_bus_error_hook_t *kgdb_bus_err_hook;
+static inline void arch_kgdb_breakpoint(void)
+{
+	__asm__ __volatile__ ("trapa #0x3c\n");
+}
 
-/* Console */
-struct console;
-void kgdb_console_write(struct console *co, const char *s, unsigned count);
-extern int kgdb_console_setup(struct console *, char *);
+/* State info */
+extern char in_nmi;		/* Debounce flag to prevent NMI reentry*/
 
-/* Prototypes for jmp fns */
-#define _JBLEN 9
-typedef        int jmp_buf[_JBLEN];
-extern void    longjmp(jmp_buf __jmpb, int __retval);
-extern int     setjmp(jmp_buf __jmpb);
+#define BUFMAX                 2048
 
-/* Forced breakpoint */
-#define breakpoint()	__asm__ __volatile__("trapa   #0x3c")
+#define CACHE_FLUSH_IS_SAFE	1
+#define BREAK_INSTR_SIZE	2
 
-#endif
+#endif /* __ASM_SH_KGDB_H */

arch/sh/include/asm/system.h

@@ -175,6 +175,8 @@ asmlinkage void name##_trap_handler(unsigned int vec, struct pt_regs *regs)
 BUILD_TRAP_HANDLER(address_error);
 BUILD_TRAP_HANDLER(debug);
 BUILD_TRAP_HANDLER(bug);
+BUILD_TRAP_HANDLER(breakpoint);
+BUILD_TRAP_HANDLER(singlestep);
 BUILD_TRAP_HANDLER(fpu_error);
 BUILD_TRAP_HANDLER(fpu_state_restore);
 

arch/sh/kernel/Makefile_32

@@ -19,7 +19,7 @@ obj-$(CONFIG_VSYSCALL)		+= vsyscall/
 obj-$(CONFIG_SMP)		+= smp.o
 obj-$(CONFIG_CF_ENABLER)	+= cf-enabler.o
 obj-$(CONFIG_SH_STANDARD_BIOS)	+= sh_bios.o
-obj-$(CONFIG_SH_KGDB)		+= kgdb_stub.o kgdb_jmp.o
+obj-$(CONFIG_KGDB)		+= kgdb.o
 obj-$(CONFIG_SH_CPU_FREQ)	+= cpufreq.o
 obj-$(CONFIG_MODULES)		+= sh_ksyms_32.o module.o
 obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o

arch/sh/kernel/cpu/sh3/entry.S

@@ -52,7 +52,7 @@
  *	syscall #
  *
  */
-#if defined(CONFIG_KGDB_NMI)
+#if defined(CONFIG_KGDB)
 NMI_VEC = 0x1c0			! Must catch early for debounce
 #endif
 
@@ -307,7 +307,7 @@ skip_restore:
 6:	or	k0, k2			! Set the IMASK-bits
 	ldc	k2, ssr
 	!
-#if defined(CONFIG_KGDB_NMI)
+#if defined(CONFIG_KGDB)
 	! Clear in_nmi
 	mov.l	6f, k0
 	mov	#0, k1
@@ -320,7 +320,7 @@ skip_restore:
 
 	.align	2
 5:	.long	0x00001000	! DSP
-#ifdef CONFIG_KGDB_NMI
+#ifdef CONFIG_KGDB
 6:	.long	in_nmi
 #endif
 7:	.long	0x30000000
@@ -377,7 +377,7 @@ tlb_miss:
 	.balign 	512,0,512
 interrupt:
 	mov.l	3f, k3
-#if defined(CONFIG_KGDB_NMI)
+#if defined(CONFIG_KGDB)
 	mov.l	2f, k2
 	! Debounce (filter nested NMI)
 	mov.l	@k2, k0
@@ -394,7 +394,7 @@ interrupt:
 5:	.long	NMI_VEC
 6:	.long	in_nmi
 0:
-#endif /* defined(CONFIG_KGDB_NMI) */
+#endif /* defined(CONFIG_KGDB) */
 	bra	handle_exception
 	 mov	#-1, k2		! interrupt exception marker
 

arch/sh/kernel/cpu/sh3/ex.S

@@ -26,7 +26,7 @@
 #define	fpu_error_trap_handler		exception_error
 #endif
 
-#if !defined(CONFIG_KGDB_NMI)
+#if !defined(CONFIG_KGDB)
 #define kgdb_handle_exception		exception_error
 #endif
 

arch/sh/kernel/debugtraps.S

@@ -3,7 +3,7 @@
  *
  * Debug trap jump tables for SuperH
  *
- *  Copyright (C) 2006  Paul Mundt
+ *  Copyright (C) 2006 - 2008  Paul Mundt
  *
  * 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
@@ -12,8 +12,9 @@
 #include <linux/sys.h>
 #include <linux/linkage.h>
 
-#if !defined(CONFIG_SH_KGDB)
-#define kgdb_handle_exception	debug_trap_handler
+#if !defined(CONFIG_KGDB)
+#define breakpoint_trap_handler		debug_trap_handler
+#define singlestep_trap_handler		debug_trap_handler
 #endif
 
 #if !defined(CONFIG_SH_STANDARD_BIOS)
@@ -35,7 +36,7 @@ ENTRY(debug_trap_table)
 	.long debug_trap_handler	/* 0x39 */
 	.long debug_trap_handler	/* 0x3a */
 	.long debug_trap_handler	/* 0x3b */
-	.long kgdb_handle_exception	/* 0x3c */
-	.long debug_trap_handler	/* 0x3d */
+	.long breakpoint_trap_handler	/* 0x3c */
+	.long singlestep_trap_handler	/* 0x3d */
 	.long bug_trap_handler		/* 0x3e */
 	.long sh_bios_handler		/* 0x3f */

arch/sh/kernel/entry-common.S

@@ -308,15 +308,19 @@ ENTRY(system_call)
 	mov.l	1f, r9
 	mov.l	@r9, r8		! Read from TRA (Trap Address) Register
 #endif
+
+	mov	#OFF_TRA, r10
+	add	r15, r10
+	mov.l	r8, @r10		! set TRA value to tra
+
 	/*
 	 * Check the trap type
 	 */
 	mov	#((0x20 << 2) - 1), r9
 	cmp/hi	r9, r8
 	bt/s	debug_trap		! it's a debug trap..
-	 mov	#OFF_TRA, r9
-	add	r15, r9
-	mov.l	r8, @r9			! set TRA value to tra
+	 nop
+
 #ifdef CONFIG_TRACE_IRQFLAGS
 	mov.l	5f, r10
 	jsr	@r10

arch/sh/kernel/kgdb.c

+/*
+ * SuperH KGDB support
+ *
+ * Copyright (C) 2008  Paul Mundt
+ *
+ * Single stepping taken from the old stub by Henry Bell and Jeremy Siegel.
+ *
+ * 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/kgdb.h>
+#include <linux/kdebug.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <asm/cacheflush.h>
+
+char in_nmi = 0;	/* Set during NMI to prevent re-entry */
+
+/* Macros for single step instruction identification */
+#define OPCODE_BT(op)		(((op) & 0xff00) == 0x8900)
+#define OPCODE_BF(op)		(((op) & 0xff00) == 0x8b00)
+#define OPCODE_BTF_DISP(op)	(((op) & 0x80) ? (((op) | 0xffffff80) << 1) : \
+				 (((op) & 0x7f ) << 1))
+#define OPCODE_BFS(op)		(((op) & 0xff00) == 0x8f00)
+#define OPCODE_BTS(op)		(((op) & 0xff00) == 0x8d00)
+#define OPCODE_BRA(op)		(((op) & 0xf000) == 0xa000)
+#define OPCODE_BRA_DISP(op)	(((op) & 0x800) ? (((op) | 0xfffff800) << 1) : \
+				 (((op) & 0x7ff) << 1))
+#define OPCODE_BRAF(op)		(((op) & 0xf0ff) == 0x0023)
+#define OPCODE_BRAF_REG(op)	(((op) & 0x0f00) >> 8)
+#define OPCODE_BSR(op)		(((op) & 0xf000) == 0xb000)
+#define OPCODE_BSR_DISP(op)	(((op) & 0x800) ? (((op) | 0xfffff800) << 1) : \
+				 (((op) & 0x7ff) << 1))
+#define OPCODE_BSRF(op)		(((op) & 0xf0ff) == 0x0003)
+#define OPCODE_BSRF_REG(op)	(((op) >> 8) & 0xf)
+#define OPCODE_JMP(op)		(((op) & 0xf0ff) == 0x402b)
+#define OPCODE_JMP_REG(op)	(((op) >> 8) & 0xf)
+#define OPCODE_JSR(op)		(((op) & 0xf0ff) == 0x400b)
+#define OPCODE_JSR_REG(op)	(((op) >> 8) & 0xf)
+#define OPCODE_RTS(op)		((op) == 0xb)
+#define OPCODE_RTE(op)		((op) == 0x2b)
+
+#define SR_T_BIT_MASK           0x1
+#define STEP_OPCODE             0xc33d
+
+/* Calculate the new address for after a step */
+static short *get_step_address(struct pt_regs *linux_regs)
+{
+	opcode_t op = __raw_readw(linux_regs->pc);
+	long addr;
+
+	/* BT */
+	if (OPCODE_BT(op)) {
+		if (linux_regs->sr & SR_T_BIT_MASK)
+			addr = linux_regs->pc + 4 + OPCODE_BTF_DISP(op);
+		else
+			addr = linux_regs->pc + 2;
+	}
+
+	/* BTS */
+	else if (OPCODE_BTS(op)) {
+		if (linux_regs->sr & SR_T_BIT_MASK)
+			addr = linux_regs->pc + 4 + OPCODE_BTF_DISP(op);
+		else
+			addr = linux_regs->pc + 4;	/* Not in delay slot */
+	}
+
+	/* BF */
+	else if (OPCODE_BF(op)) {
+		if (!(linux_regs->sr & SR_T_BIT_MASK))
+			addr = linux_regs->pc + 4 + OPCODE_BTF_DISP(op);
+		else
+			addr = linux_regs->pc + 2;
+	}
+
+	/* BFS */
+	else if (OPCODE_BFS(op)) {
+		if (!(linux_regs->sr & SR_T_BIT_MASK))
+			addr = linux_regs->pc + 4 + OPCODE_BTF_DISP(op);
+		else
+			addr = linux_regs->pc + 4;	/* Not in delay slot */
+	}
+
+	/* BRA */
+	else if (OPCODE_BRA(op))
+		addr = linux_regs->pc + 4 + OPCODE_BRA_DISP(op);
+
+	/* BRAF */
+	else if (OPCODE_BRAF(op))
+		addr = linux_regs->pc + 4
+		    + linux_regs->regs[OPCODE_BRAF_REG(op)];
+
+	/* BSR */
+	else if (OPCODE_BSR(op))
+		addr = linux_regs->pc + 4 + OPCODE_BSR_DISP(op);
+
+	/* BSRF */
+	else if (OPCODE_BSRF(op))
+		addr = linux_regs->pc + 4
+		    + linux_regs->regs[OPCODE_BSRF_REG(op)];
+
+	/* JMP */
+	else if (OPCODE_JMP(op))
+		addr = linux_regs->regs[OPCODE_JMP_REG(op)];
+
+	/* JSR */
+	else if (OPCODE_JSR(op))
+		addr = linux_regs->regs[OPCODE_JSR_REG(op)];
+
+	/* RTS */
+	else if (OPCODE_RTS(op))
+		addr = linux_regs->pr;
+
+	/* RTE */
+	else if (OPCODE_RTE(op))
+		addr = linux_regs->regs[15];
+
+	/* Other */
+	else
+		addr = linux_regs->pc + instruction_size(op);
+
+	flush_icache_range(addr, addr + instruction_size(op));
+	return (short *)addr;
+}
+
+/*
+ * Replace the instruction immediately after the current instruction
+ * (i.e. next in the expected flow of control) with a trap instruction,
+ * so that returning will cause only a single instruction to be executed.
+ * Note that this model is slightly broken for instructions with delay
+ * slots (e.g. B[TF]S, BSR, BRA etc), where both the branch and the
+ * instruction in the delay slot will be executed.
+ */
+
+static unsigned long stepped_address;
+static opcode_t stepped_opcode;
+
+static void do_single_step(struct pt_regs *linux_regs)
+{
+	/* Determine where the target instruction will send us to */
+	unsigned short *addr = get_step_address(linux_regs);
+
+	stepped_address = (int)addr;
+
+	/* Replace it */
+	stepped_opcode = __raw_readw((long)addr);
+	*addr = STEP_OPCODE;
+
+	/* Flush and return */
+	flush_icache_range((long)addr, (long)addr +
+			   instruction_size(stepped_opcode));
+}
+
+/* Undo a single step */
+static void undo_single_step(struct pt_regs *linux_regs)
+{
+	/* If we have stepped, put back the old instruction */
+	/* Use stepped_address in case we stopped elsewhere */
+	if (stepped_opcode != 0) {
+		__raw_writew(stepped_opcode, stepped_address);
+		flush_icache_range(stepped_address, stepped_address + 2);
+	}
+
+	stepped_opcode = 0;
+}
+
+void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
+{
+	int i;
+
+	for (i = 0; i < 16; i++)
+		gdb_regs[GDB_R0 + i] = regs->regs[i];
+
+	gdb_regs[GDB_PC] = regs->pc;
+	gdb_regs[GDB_PR] = regs->pr;
+	gdb_regs[GDB_SR] = regs->sr;
+	gdb_regs[GDB_GBR] = regs->gbr;
+	gdb_regs[GDB_MACH] = regs->mach;
+	gdb_regs[GDB_MACL] = regs->macl;
+
+	__asm__ __volatile__ ("stc vbr, %0" : "=r" (gdb_regs[GDB_VBR]));
+}
+
+void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
+{
+	int i;
+
+	for (i = 0; i < 16; i++)
+		regs->regs[GDB_R0 + i] = gdb_regs[GDB_R0 + i];
+
+	regs->pc = gdb_regs[GDB_PC];
+	regs->pr = gdb_regs[GDB_PR];
+	regs->sr = gdb_regs[GDB_SR];
+	regs->gbr = gdb_regs[GDB_GBR];
+	regs->mach = gdb_regs[GDB_MACH];
+	regs->macl = gdb_regs[GDB_MACL];
+
+	__asm__ __volatile__ ("ldc %0, vbr" : : "r" (gdb_regs[GDB_VBR]));
+}
+
+void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
+{
+	gdb_regs[GDB_R15] = p->thread.sp;
+	gdb_regs[GDB_PC] = p->thread.pc;
+}
+
+int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
+			       char *remcomInBuffer, char *remcomOutBuffer,
+			       struct pt_regs *linux_regs)
+{
+	unsigned long addr;
+	char *ptr;
+
+	/* Undo any stepping we may have done */
+	undo_single_step(linux_regs);
+
+	switch (remcomInBuffer[0]) {
+	case 'c':
+	case 's':
+		/* try to read optional parameter, pc unchanged if no parm */
+		ptr = &remcomInBuffer[1];
+		if (kgdb_hex2long(&ptr, &addr))
+			linux_regs->pc = addr;
+	case 'D':
+	case 'k':
+		atomic_set(&kgdb_cpu_doing_single_step, -1);
+
+		if (remcomInBuffer[0] == 's') {
+			do_single_step(linux_regs);
+			kgdb_single_step = 1;
+
+			atomic_set(&kgdb_cpu_doing_single_step,
+				   raw_smp_processor_id());
+		}
+
+		return 0;
+	}
+
+	/* this means that we do not want to exit from the handler: */
+	return -1;
+}
+
+/*
+ * The primary entry points for the kgdb debug trap table entries.
+ */
+BUILD_TRAP_HANDLER(singlestep)
+{
+	unsigned long flags;
+	TRAP_HANDLER_DECL;
+
+	local_irq_save(flags);
+	regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
+	kgdb_handle_exception(vec >> 2, SIGTRAP, 0, regs);
+	local_irq_restore(flags);
+}
+
+
+BUILD_TRAP_HANDLER(breakpoint)
+{
+	unsigned long flags;
+	TRAP_HANDLER_DECL;
+
+	local_irq_save(flags);
+	kgdb_handle_exception(vec >> 2, SIGTRAP, 0, regs);
+	local_irq_restore(flags);
+}
+
+int kgdb_arch_init(void)
+{
+	return 0;
+}
+
+void kgdb_arch_exit(void)
+{
+}
+
+struct kgdb_arch arch_kgdb_ops = {
+	/* Breakpoint instruction: trapa #0x3c */
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+	.gdb_bpt_instr		= { 0x3c, 0xc3 },
+#else
+	.gdb_bpt_instr		= { 0xc3, 0x3c },
+#endif
+};

arch/sh/kernel/kgdb_jmp.S

-#include <linux/linkage.h>
-
-ENTRY(setjmp)
-	add	#(9*4), r4
-	sts.l	pr, @-r4
-	mov.l	r15, @-r4
-	mov.l	r14, @-r4
-	mov.l	r13, @-r4
-	mov.l	r12, @-r4
-	mov.l	r11, @-r4
-	mov.l	r10, @-r4
-	mov.l	r9, @-r4
-	mov.l	r8, @-r4
-	rts
-	 mov	#0, r0
-
-ENTRY(longjmp)
-	mov.l	@r4+, r8
-	mov.l	@r4+, r9
-	mov.l	@r4+, r10
-	mov.l	@r4+, r11
-	mov.l	@r4+, r12
-	mov.l	@r4+, r13
-	mov.l	@r4+, r14
-	mov.l	@r4+, r15
-	lds.l	@r4+, pr
-	mov	r5, r0
-	tst	r0, r0
-	bf	1f
-	mov	#1, r0	! in case val==0
-1:	rts
-	 nop
-

arch/sh/kernel/time_32.c

@@ -277,11 +277,4 @@ void __init time_init(void)
 		       ((sh_hpt_frequency + 500) / 1000) / 1000,
 		       ((sh_hpt_frequency + 500) / 1000) % 1000);
 
-#if defined(CONFIG_SH_KGDB)
-	/*
-	 * Set up kgdb as requested. We do it here because the serial
-	 * init uses the timer vars we just set up for figuring baud.
-	 */
-	kgdb_init();
-#endif
 }

arch/sh/kernel/traps_32.c

@@ -28,17 +28,6 @@
 #include <asm/fpu.h>
 #include <asm/kprobes.h>
 
-#ifdef CONFIG_SH_KGDB
-#include <asm/kgdb.h>
-#define CHK_REMOTE_DEBUG(regs)			\
-{						\
-	if (kgdb_debug_hook && !user_mode(regs))\
-		(*kgdb_debug_hook)(regs);       \
-}
-#else
-#define CHK_REMOTE_DEBUG(regs)
-#endif
-
 #ifdef CONFIG_CPU_SH2
 # define TRAP_RESERVED_INST	4
 # define TRAP_ILLEGAL_SLOT_INST	6
@@ -94,7 +83,6 @@ void die(const char * str, struct pt_regs * regs, long err)
 
 	printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
 
-	CHK_REMOTE_DEBUG(regs);
 	print_modules();
 	show_regs(regs);
 
@@ -683,7 +671,6 @@ asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
 	error_code = lookup_exception_vector();
 
 	local_irq_enable();
-	CHK_REMOTE_DEBUG(regs);
 	force_sig(SIGILL, tsk);
 	die_if_no_fixup("reserved instruction", regs, error_code);
 }
@@ -761,7 +748,6 @@ asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5,
 	inst = lookup_exception_vector();
 
 	local_irq_enable();
-	CHK_REMOTE_DEBUG(regs);
 	force_sig(SIGILL, tsk);
 	die_if_no_fixup("illegal slot instruction", regs, inst);
 }

arch/sh/mm/fault_32.c

@@ -20,7 +20,6 @@
 #include <asm/system.h>
 #include <asm/mmu_context.h>
 #include <asm/tlbflush.h>
-#include <asm/kgdb.h>
 
 /*
  * This routine handles page faults.  It determines the address,
@@ -282,11 +281,6 @@ asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs,
 	if (notify_page_fault(regs, lookup_exception_vector()))
 		goto out;
 
-#ifdef CONFIG_SH_KGDB
-	if (kgdb_nofault && kgdb_bus_err_hook)
-		kgdb_bus_err_hook();
-#endif
-
 	ret = 1;
 
 	/*