Adding upstream version 5.10.209.upstream/5.10.209upstream

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

1 files changed, 1181 insertions, 0 deletions

diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c
new file mode 100644
index 000000000..3e4d89471
--- /dev/null
+++ b/drivers/misc/kgdbts.c
@@ -0,0 +1,1181 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * kgdbts is a test suite for kgdb for the sole purpose of validating
+ * that key pieces of the kgdb internals are working properly such as
+ * HW/SW breakpoints, single stepping, and NMI.
+ *
+ * Created by: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (c) 2008 Wind River Systems, Inc.
+ */
+/* Information about the kgdb test suite.
+ * -------------------------------------
+ *
+ * The kgdb test suite is designed as a KGDB I/O module which
+ * simulates the communications that a debugger would have with kgdb.
+ * The tests are broken up in to a line by line and referenced here as
+ * a "get" which is kgdb requesting input and "put" which is kgdb
+ * sending a response.
+ *
+ * The kgdb suite can be invoked from the kernel command line
+ * arguments system or executed dynamically at run time.  The test
+ * suite uses the variable "kgdbts" to obtain the information about
+ * which tests to run and to configure the verbosity level.  The
+ * following are the various characters you can use with the kgdbts=
+ * line:
+ *
+ * When using the "kgdbts=" you only choose one of the following core
+ * test types:
+ * A = Run all the core tests silently
+ * V1 = Run all the core tests with minimal output
+ * V2 = Run all the core tests in debug mode
+ *
+ * You can also specify optional tests:
+ * N## = Go to sleep with interrupts of for ## seconds
+ *       to test the HW NMI watchdog
+ * F## = Break at kernel_clone for ## iterations
+ * S## = Break at sys_open for ## iterations
+ * I## = Run the single step test ## iterations
+ *
+ * NOTE: that the kernel_clone and sys_open tests are mutually exclusive.
+ *
+ * To invoke the kgdb test suite from boot you use a kernel start
+ * argument as follows:
+ * 	kgdbts=V1 kgdbwait
+ * Or if you wanted to perform the NMI test for 6 seconds and kernel_clone
+ * test for 100 forks, you could use:
+ * 	kgdbts=V1N6F100 kgdbwait
+ *
+ * The test suite can also be invoked at run time with:
+ *	echo kgdbts=V1N6F100 > /sys/module/kgdbts/parameters/kgdbts
+ * Or as another example:
+ *	echo kgdbts=V2 > /sys/module/kgdbts/parameters/kgdbts
+ *
+ * When developing a new kgdb arch specific implementation or
+ * using these tests for the purpose of regression testing,
+ * several invocations are required.
+ *
+ * 1) Boot with the test suite enabled by using the kernel arguments
+ *       "kgdbts=V1F100 kgdbwait"
+ *    ## If kgdb arch specific implementation has NMI use
+ *       "kgdbts=V1N6F100
+ *
+ * 2) After the system boot run the basic test.
+ * echo kgdbts=V1 > /sys/module/kgdbts/parameters/kgdbts
+ *
+ * 3) Run the concurrency tests.  It is best to use n+1
+ *    while loops where n is the number of cpus you have
+ *    in your system.  The example below uses only two
+ *    loops.
+ *
+ * ## This tests break points on sys_open
+ * while [ 1 ] ; do find / > /dev/null 2>&1 ; done &
+ * while [ 1 ] ; do find / > /dev/null 2>&1 ; done &
+ * echo kgdbts=V1S10000 > /sys/module/kgdbts/parameters/kgdbts
+ * fg # and hit control-c
+ * fg # and hit control-c
+ * ## This tests break points on kernel_clone
+ * while [ 1 ] ; do date > /dev/null ; done &
+ * while [ 1 ] ; do date > /dev/null ; done &
+ * echo kgdbts=V1F1000 > /sys/module/kgdbts/parameters/kgdbts
+ * fg # and hit control-c
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/kgdb.h>
+#include <linux/ctype.h>
+#include <linux/uaccess.h>
+#include <linux/syscalls.h>
+#include <linux/nmi.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/sched/task.h>
+
+#include <asm/sections.h>
+
+#define v1printk(a...) do {		\
+	if (verbose)			\
+		printk(KERN_INFO a);	\
+} while (0)
+#define v2printk(a...) do {		\
+	if (verbose > 1) {		\
+		printk(KERN_INFO a);	\
+	}				\
+	touch_nmi_watchdog();		\
+} while (0)
+#define eprintk(a...) do {		\
+	printk(KERN_ERR a);		\
+	WARN_ON(1);			\
+} while (0)
+#define MAX_CONFIG_LEN		40
+
+static struct kgdb_io kgdbts_io_ops;
+static char get_buf[BUFMAX];
+static int get_buf_cnt;
+static char put_buf[BUFMAX];
+static int put_buf_cnt;
+static char scratch_buf[BUFMAX];
+static int verbose;
+static int repeat_test;
+static int test_complete;
+static int send_ack;
+static int final_ack;
+static int force_hwbrks;
+static int hwbreaks_ok;
+static int hw_break_val;
+static int hw_break_val2;
+static int cont_instead_of_sstep;
+static unsigned long cont_thread_id;
+static unsigned long sstep_thread_id;
+#if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || defined(CONFIG_SPARC)
+static int arch_needs_sstep_emulation = 1;
+#else
+static int arch_needs_sstep_emulation;
+#endif
+static unsigned long cont_addr;
+static unsigned long sstep_addr;
+static int restart_from_top_after_write;
+static int sstep_state;
+
+/* Storage for the registers, in GDB format. */
+static unsigned long kgdbts_gdb_regs[(NUMREGBYTES +
+					sizeof(unsigned long) - 1) /
+					sizeof(unsigned long)];
+static struct pt_regs kgdbts_regs;
+
+/* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
+static int configured		= -1;
+
+#ifdef CONFIG_KGDB_TESTS_BOOT_STRING
+static char config[MAX_CONFIG_LEN] = CONFIG_KGDB_TESTS_BOOT_STRING;
+#else
+static char config[MAX_CONFIG_LEN];
+#endif
+static struct kparam_string kps = {
+	.string			= config,
+	.maxlen			= MAX_CONFIG_LEN,
+};
+
+static void fill_get_buf(char *buf);
+
+struct test_struct {
+	char *get;
+	char *put;
+	void (*get_handler)(char *);
+	int (*put_handler)(char *, char *);
+};
+
+struct test_state {
+	char *name;
+	struct test_struct *tst;
+	int idx;
+	int (*run_test) (int, int);
+	int (*validate_put) (char *);
+};
+
+static struct test_state ts;
+
+static int kgdbts_unreg_thread(void *ptr)
+{
+	/* Wait until the tests are complete and then ungresiter the I/O
+	 * driver.
+	 */
+	while (!final_ack)
+		msleep_interruptible(1500);
+	/* Pause for any other threads to exit after final ack. */
+	msleep_interruptible(1000);
+	if (configured)
+		kgdb_unregister_io_module(&kgdbts_io_ops);
+	configured = 0;
+
+	return 0;
+}
+
+/* This is noinline such that it can be used for a single location to
+ * place a breakpoint
+ */
+static noinline void kgdbts_break_test(void)
+{
+	v2printk("kgdbts: breakpoint complete\n");
+}
+
+/* Lookup symbol info in the kernel */
+static unsigned long lookup_addr(char *arg)
+{
+	unsigned long addr = 0;
+
+	if (!strcmp(arg, "kgdbts_break_test"))
+		addr = (unsigned long)kgdbts_break_test;
+	else if (!strcmp(arg, "sys_open"))
+		addr = (unsigned long)do_sys_open;
+	else if (!strcmp(arg, "kernel_clone"))
+		addr = (unsigned long)kernel_clone;
+	else if (!strcmp(arg, "hw_break_val"))
+		addr = (unsigned long)&hw_break_val;
+	addr = (unsigned long) dereference_function_descriptor((void *)addr);
+	return addr;
+}
+
+static void break_helper(char *bp_type, char *arg, unsigned long vaddr)
+{
+	unsigned long addr;
+
+	if (arg)
+		addr = lookup_addr(arg);
+	else
+		addr = vaddr;
+
+	sprintf(scratch_buf, "%s,%lx,%i", bp_type, addr,
+		BREAK_INSTR_SIZE);
+	fill_get_buf(scratch_buf);
+}
+
+static void sw_break(char *arg)
+{
+	break_helper(force_hwbrks ? "Z1" : "Z0", arg, 0);
+}
+
+static void sw_rem_break(char *arg)
+{
+	break_helper(force_hwbrks ? "z1" : "z0", arg, 0);
+}
+
+static void hw_break(char *arg)
+{
+	break_helper("Z1", arg, 0);
+}
+
+static void hw_rem_break(char *arg)
+{
+	break_helper("z1", arg, 0);
+}
+
+static void hw_write_break(char *arg)
+{
+	break_helper("Z2", arg, 0);
+}
+
+static void hw_rem_write_break(char *arg)
+{
+	break_helper("z2", arg, 0);
+}
+
+static void hw_access_break(char *arg)
+{
+	break_helper("Z4", arg, 0);
+}
+
+static void hw_rem_access_break(char *arg)
+{
+	break_helper("z4", arg, 0);
+}
+
+static void hw_break_val_access(void)
+{
+	hw_break_val2 = hw_break_val;
+}
+
+static void hw_break_val_write(void)
+{
+	hw_break_val++;
+}
+
+static int get_thread_id_continue(char *put_str, char *arg)
+{
+	char *ptr = &put_str[11];
+
+	if (put_str[1] != 'T' || put_str[2] != '0')
+		return 1;
+	kgdb_hex2long(&ptr, &cont_thread_id);
+	return 0;
+}
+
+static int check_and_rewind_pc(char *put_str, char *arg)
+{
+	unsigned long addr = lookup_addr(arg);
+	unsigned long ip;
+	int offset = 0;
+
+	kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
+		 NUMREGBYTES);
+	gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
+	ip = instruction_pointer(&kgdbts_regs);
+	v2printk("Stopped at IP: %lx\n", ip);
+#ifdef GDB_ADJUSTS_BREAK_OFFSET
+	/* On some arches, a breakpoint stop requires it to be decremented */
+	if (addr + BREAK_INSTR_SIZE == ip)
+		offset = -BREAK_INSTR_SIZE;
+#endif
+
+	if (arch_needs_sstep_emulation && sstep_addr &&
+	    ip + offset == sstep_addr &&
+	    ((!strcmp(arg, "sys_open") || !strcmp(arg, "kernel_clone")))) {
+		/* This is special case for emulated single step */
+		v2printk("Emul: rewind hit single step bp\n");
+		restart_from_top_after_write = 1;
+	} else if (strcmp(arg, "silent") && ip + offset != addr) {
+		eprintk("kgdbts: BP mismatch %lx expected %lx\n",
+			   ip + offset, addr);
+		return 1;
+	}
+	/* Readjust the instruction pointer if needed */
+	ip += offset;
+	cont_addr = ip;
+#ifdef GDB_ADJUSTS_BREAK_OFFSET
+	instruction_pointer_set(&kgdbts_regs, ip);
+#endif
+	return 0;
+}
+
+static int check_single_step(char *put_str, char *arg)
+{
+	unsigned long addr = lookup_addr(arg);
+	static int matched_id;
+
+	/*
+	 * From an arch indepent point of view the instruction pointer
+	 * should be on a different instruction
+	 */
+	kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
+		 NUMREGBYTES);
+	gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
+	v2printk("Singlestep stopped at IP: %lx\n",
+		   instruction_pointer(&kgdbts_regs));
+
+	if (sstep_thread_id != cont_thread_id) {
+		/*
+		 * Ensure we stopped in the same thread id as before, else the
+		 * debugger should continue until the original thread that was
+		 * single stepped is scheduled again, emulating gdb's behavior.
+		 */
+		v2printk("ThrID does not match: %lx\n", cont_thread_id);
+		if (arch_needs_sstep_emulation) {
+			if (matched_id &&
+			    instruction_pointer(&kgdbts_regs) != addr)
+				goto continue_test;
+			matched_id++;
+			ts.idx -= 2;
+			sstep_state = 0;
+			return 0;
+		}
+		cont_instead_of_sstep = 1;
+		ts.idx -= 4;
+		return 0;
+	}
+continue_test:
+	matched_id = 0;
+	if (instruction_pointer(&kgdbts_regs) == addr) {
+		eprintk("kgdbts: SingleStep failed at %lx\n",
+			   instruction_pointer(&kgdbts_regs));
+		return 1;
+	}
+
+	return 0;
+}
+
+static void write_regs(char *arg)
+{
+	memset(scratch_buf, 0, sizeof(scratch_buf));
+	scratch_buf[0] = 'G';
+	pt_regs_to_gdb_regs(kgdbts_gdb_regs, &kgdbts_regs);
+	kgdb_mem2hex((char *)kgdbts_gdb_regs, &scratch_buf[1], NUMREGBYTES);
+	fill_get_buf(scratch_buf);
+}
+
+static void skip_back_repeat_test(char *arg)
+{
+	int go_back = simple_strtol(arg, NULL, 10);
+
+	repeat_test--;
+	if (repeat_test <= 0) {
+		ts.idx++;
+	} else {
+		if (repeat_test % 100 == 0)
+			v1printk("kgdbts:RUN ... %d remaining\n", repeat_test);
+
+		ts.idx -= go_back;
+	}
+	fill_get_buf(ts.tst[ts.idx].get);
+}
+
+static int got_break(char *put_str, char *arg)
+{
+	test_complete = 1;
+	if (!strncmp(put_str+1, arg, 2)) {
+		if (!strncmp(arg, "T0", 2))
+			test_complete = 2;
+		return 0;
+	}
+	return 1;
+}
+
+static void get_cont_catch(char *arg)
+{
+	/* Always send detach because the test is completed at this point */
+	fill_get_buf("D");
+}
+
+static int put_cont_catch(char *put_str, char *arg)
+{
+	/* This is at the end of the test and we catch any and all input */
+	v2printk("kgdbts: cleanup task: %lx\n", sstep_thread_id);
+	ts.idx--;
+	return 0;
+}
+
+static int emul_reset(char *put_str, char *arg)
+{
+	if (strncmp(put_str, "$OK", 3))
+		return 1;
+	if (restart_from_top_after_write) {
+		restart_from_top_after_write = 0;
+		ts.idx = -1;
+	}
+	return 0;
+}
+
+static void emul_sstep_get(char *arg)
+{
+	if (!arch_needs_sstep_emulation) {
+		if (cont_instead_of_sstep) {
+			cont_instead_of_sstep = 0;
+			fill_get_buf("c");
+		} else {
+			fill_get_buf(arg);
+		}
+		return;
+	}
+	switch (sstep_state) {
+	case 0:
+		v2printk("Emulate single step\n");
+		/* Start by looking at the current PC */
+		fill_get_buf("g");
+		break;
+	case 1:
+		/* set breakpoint */
+		break_helper("Z0", NULL, sstep_addr);
+		break;
+	case 2:
+		/* Continue */
+		fill_get_buf("c");
+		break;
+	case 3:
+		/* Clear breakpoint */
+		break_helper("z0", NULL, sstep_addr);
+		break;
+	default:
+		eprintk("kgdbts: ERROR failed sstep get emulation\n");
+	}
+	sstep_state++;
+}
+
+static int emul_sstep_put(char *put_str, char *arg)
+{
+	if (!arch_needs_sstep_emulation) {
+		char *ptr = &put_str[11];
+		if (put_str[1] != 'T' || put_str[2] != '0')
+			return 1;
+		kgdb_hex2long(&ptr, &sstep_thread_id);
+		return 0;
+	}
+	switch (sstep_state) {
+	case 1:
+		/* validate the "g" packet to get the IP */
+		kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
+			 NUMREGBYTES);
+		gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
+		v2printk("Stopped at IP: %lx\n",
+			 instruction_pointer(&kgdbts_regs));
+		/* Want to stop at IP + break instruction size by default */
+		sstep_addr = cont_addr + BREAK_INSTR_SIZE;
+		break;
+	case 2:
+		if (strncmp(put_str, "$OK", 3)) {
+			eprintk("kgdbts: failed sstep break set\n");
+			return 1;
+		}
+		break;
+	case 3:
+		if (strncmp(put_str, "$T0", 3)) {
+			eprintk("kgdbts: failed continue sstep\n");
+			return 1;
+		} else {
+			char *ptr = &put_str[11];
+			kgdb_hex2long(&ptr, &sstep_thread_id);
+		}
+		break;
+	case 4:
+		if (strncmp(put_str, "$OK", 3)) {
+			eprintk("kgdbts: failed sstep break unset\n");
+			return 1;
+		}
+		/* Single step is complete so continue on! */
+		sstep_state = 0;
+		return 0;
+	default:
+		eprintk("kgdbts: ERROR failed sstep put emulation\n");
+	}
+
+	/* Continue on the same test line until emulation is complete */
+	ts.idx--;
+	return 0;
+}
+
+static int final_ack_set(char *put_str, char *arg)
+{
+	if (strncmp(put_str+1, arg, 2))
+		return 1;
+	final_ack = 1;
+	return 0;
+}
+/*
+ * Test to plant a breakpoint and detach, which should clear out the
+ * breakpoint and restore the original instruction.
+ */
+static struct test_struct plant_and_detach_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
+	{ "D", "OK" }, /* Detach */
+	{ "", "" },
+};
+
+/*
+ * Simple test to write in a software breakpoint, check for the
+ * correct stop location and detach.
+ */
+static struct test_struct sw_breakpoint_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
+	{ "c", "T0*", }, /* Continue */
+	{ "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
+	{ "write", "OK", write_regs },
+	{ "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
+	{ "D", "OK" }, /* Detach */
+	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
+	{ "", "" },
+};
+
+/*
+ * Test a known bad memory read location to test the fault handler and
+ * read bytes 1-8 at the bad address
+ */
+static struct test_struct bad_read_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "m0,1", "E*" }, /* read 1 byte at address 1 */
+	{ "m0,2", "E*" }, /* read 1 byte at address 2 */
+	{ "m0,3", "E*" }, /* read 1 byte at address 3 */
+	{ "m0,4", "E*" }, /* read 1 byte at address 4 */
+	{ "m0,5", "E*" }, /* read 1 byte at address 5 */
+	{ "m0,6", "E*" }, /* read 1 byte at address 6 */
+	{ "m0,7", "E*" }, /* read 1 byte at address 7 */
+	{ "m0,8", "E*" }, /* read 1 byte at address 8 */
+	{ "D", "OK" }, /* Detach which removes all breakpoints and continues */
+	{ "", "" },
+};
+
+/*
+ * Test for hitting a breakpoint, remove it, single step, plant it
+ * again and detach.
+ */
+static struct test_struct singlestep_break_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
+	{ "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
+	{ "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
+	{ "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
+	{ "write", "OK", write_regs }, /* Write registers */
+	{ "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
+	{ "g", "kgdbts_break_test", NULL, check_single_step },
+	{ "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
+	{ "c", "T0*", }, /* Continue */
+	{ "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
+	{ "write", "OK", write_regs }, /* Write registers */
+	{ "D", "OK" }, /* Remove all breakpoints and continues */
+	{ "", "" },
+};
+
+/*
+ * Test for hitting a breakpoint at kernel_clone for what ever the number
+ * of iterations required by the variable repeat_test.
+ */
+static struct test_struct do_kernel_clone_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "kernel_clone", "OK", sw_break, }, /* set sw breakpoint */
+	{ "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
+	{ "kernel_clone", "OK", sw_rem_break }, /*remove breakpoint */
+	{ "g", "kernel_clone", NULL, check_and_rewind_pc }, /* check location */
+	{ "write", "OK", write_regs, emul_reset }, /* Write registers */
+	{ "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
+	{ "g", "kernel_clone", NULL, check_single_step },
+	{ "kernel_clone", "OK", sw_break, }, /* set sw breakpoint */
+	{ "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
+	{ "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
+	{ "", "", get_cont_catch, put_cont_catch },
+};
+
+/* Test for hitting a breakpoint at sys_open for what ever the number
+ * of iterations required by the variable repeat_test.
+ */
+static struct test_struct sys_open_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "sys_open", "OK", sw_break, }, /* set sw breakpoint */
+	{ "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
+	{ "sys_open", "OK", sw_rem_break }, /*remove breakpoint */
+	{ "g", "sys_open", NULL, check_and_rewind_pc }, /* check location */
+	{ "write", "OK", write_regs, emul_reset }, /* Write registers */
+	{ "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
+	{ "g", "sys_open", NULL, check_single_step },
+	{ "sys_open", "OK", sw_break, }, /* set sw breakpoint */
+	{ "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
+	{ "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
+	{ "", "", get_cont_catch, put_cont_catch },
+};
+
+/*
+ * Test for hitting a simple hw breakpoint
+ */
+static struct test_struct hw_breakpoint_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "kgdbts_break_test", "OK", hw_break, }, /* set hw breakpoint */
+	{ "c", "T0*", }, /* Continue */
+	{ "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
+	{ "write", "OK", write_regs },
+	{ "kgdbts_break_test", "OK", hw_rem_break }, /*remove breakpoint */
+	{ "D", "OK" }, /* Detach */
+	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
+	{ "", "" },
+};
+
+/*
+ * Test for hitting a hw write breakpoint
+ */
+static struct test_struct hw_write_break_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "hw_break_val", "OK", hw_write_break, }, /* set hw breakpoint */
+	{ "c", "T0*", NULL, got_break }, /* Continue */
+	{ "g", "silent", NULL, check_and_rewind_pc },
+	{ "write", "OK", write_regs },
+	{ "hw_break_val", "OK", hw_rem_write_break }, /*remove breakpoint */
+	{ "D", "OK" }, /* Detach */
+	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
+	{ "", "" },
+};
+
+/*
+ * Test for hitting a hw access breakpoint
+ */
+static struct test_struct hw_access_break_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "hw_break_val", "OK", hw_access_break, }, /* set hw breakpoint */
+	{ "c", "T0*", NULL, got_break }, /* Continue */
+	{ "g", "silent", NULL, check_and_rewind_pc },
+	{ "write", "OK", write_regs },
+	{ "hw_break_val", "OK", hw_rem_access_break }, /*remove breakpoint */
+	{ "D", "OK" }, /* Detach */
+	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
+	{ "", "" },
+};
+
+/*
+ * Test for hitting a hw access breakpoint
+ */
+static struct test_struct nmi_sleep_test[] = {
+	{ "?", "S0*" }, /* Clear break points */
+	{ "c", "T0*", NULL, got_break }, /* Continue */
+	{ "D", "OK" }, /* Detach */
+	{ "D", "OK", NULL,  got_break }, /* On success we made it here */
+	{ "", "" },
+};
+
+static void fill_get_buf(char *buf)
+{
+	unsigned char checksum = 0;
+	int count = 0;
+	char ch;
+
+	strcpy(get_buf, "$");
+	strcat(get_buf, buf);
+	while ((ch = buf[count])) {
+		checksum += ch;
+		count++;
+	}
+	strcat(get_buf, "#");
+	get_buf[count + 2] = hex_asc_hi(checksum);
+	get_buf[count + 3] = hex_asc_lo(checksum);
+	get_buf[count + 4] = '\0';
+	v2printk("get%i: %s\n", ts.idx, get_buf);
+}
+
+static int validate_simple_test(char *put_str)
+{
+	char *chk_str;
+
+	if (ts.tst[ts.idx].put_handler)
+		return ts.tst[ts.idx].put_handler(put_str,
+			ts.tst[ts.idx].put);
+
+	chk_str = ts.tst[ts.idx].put;
+	if (*put_str == '$')
+		put_str++;
+
+	while (*chk_str != '\0' && *put_str != '\0') {
+		/* If someone does a * to match the rest of the string, allow
+		 * it, or stop if the received string is complete.
+		 */
+		if (*put_str == '#' || *chk_str == '*')
+			return 0;
+		if (*put_str != *chk_str)
+			return 1;
+
+		chk_str++;
+		put_str++;
+	}
+	if (*chk_str == '\0' && (*put_str == '\0' || *put_str == '#'))
+		return 0;
+
+	return 1;
+}
+
+static int run_simple_test(int is_get_char, int chr)
+{
+	int ret = 0;
+	if (is_get_char) {
+		/* Send an ACK on the get if a prior put completed and set the
+		 * send ack variable
+		 */
+		if (send_ack) {
+			send_ack = 0;
+			return '+';
+		}
+		/* On the first get char, fill the transmit buffer and then
+		 * take from the get_string.
+		 */
+		if (get_buf_cnt == 0) {
+			if (ts.tst[ts.idx].get_handler)
+				ts.tst[ts.idx].get_handler(ts.tst[ts.idx].get);
+			else
+				fill_get_buf(ts.tst[ts.idx].get);
+		}
+
+		if (get_buf[get_buf_cnt] == '\0') {
+			eprintk("kgdbts: ERROR GET: EOB on '%s' at %i\n",
+			   ts.name, ts.idx);
+			get_buf_cnt = 0;
+			fill_get_buf("D");
+		}
+		ret = get_buf[get_buf_cnt];
+		get_buf_cnt++;
+		return ret;
+	}
+
+	/* This callback is a put char which is when kgdb sends data to
+	 * this I/O module.
+	 */
+	if (ts.tst[ts.idx].get[0] == '\0' && ts.tst[ts.idx].put[0] == '\0' &&
+	    !ts.tst[ts.idx].get_handler) {
+		eprintk("kgdbts: ERROR: beyond end of test on"
+			   " '%s' line %i\n", ts.name, ts.idx);
+		return 0;
+	}
+
+	if (put_buf_cnt >= BUFMAX) {
+		eprintk("kgdbts: ERROR: put buffer overflow on"
+			   " '%s' line %i\n", ts.name, ts.idx);
+		put_buf_cnt = 0;
+		return 0;
+	}
+	/* Ignore everything until the first valid packet start '$' */
+	if (put_buf_cnt == 0 && chr != '$')
+		return 0;
+
+	put_buf[put_buf_cnt] = chr;
+	put_buf_cnt++;
+
+	/* End of packet == #XX so look for the '#' */
+	if (put_buf_cnt > 3 && put_buf[put_buf_cnt - 3] == '#') {
+		if (put_buf_cnt >= BUFMAX) {
+			eprintk("kgdbts: ERROR: put buffer overflow on"
+				" '%s' line %i\n", ts.name, ts.idx);
+			put_buf_cnt = 0;
+			return 0;
+		}
+		put_buf[put_buf_cnt] = '\0';
+		v2printk("put%i: %s\n", ts.idx, put_buf);
+		/* Trigger check here */
+		if (ts.validate_put && ts.validate_put(put_buf)) {
+			eprintk("kgdbts: ERROR PUT: end of test "
+			   "buffer on '%s' line %i expected %s got %s\n",
+			   ts.name, ts.idx, ts.tst[ts.idx].put, put_buf);
+		}
+		ts.idx++;
+		put_buf_cnt = 0;
+		get_buf_cnt = 0;
+		send_ack = 1;
+	}
+	return 0;
+}
+
+static void init_simple_test(void)
+{
+	memset(&ts, 0, sizeof(ts));
+	ts.run_test = run_simple_test;
+	ts.validate_put = validate_simple_test;
+}
+
+static void run_plant_and_detach_test(int is_early)
+{
+	char before[BREAK_INSTR_SIZE];
+	char after[BREAK_INSTR_SIZE];
+
+	copy_from_kernel_nofault(before, (char *)kgdbts_break_test,
+	  BREAK_INSTR_SIZE);
+	init_simple_test();
+	ts.tst = plant_and_detach_test;
+	ts.name = "plant_and_detach_test";
+	/* Activate test with initial breakpoint */
+	if (!is_early)
+		kgdb_breakpoint();
+	copy_from_kernel_nofault(after, (char *)kgdbts_break_test,
+			BREAK_INSTR_SIZE);
+	if (memcmp(before, after, BREAK_INSTR_SIZE)) {
+		printk(KERN_CRIT "kgdbts: ERROR kgdb corrupted memory\n");
+		panic("kgdb memory corruption");
+	}
+
+	/* complete the detach test */
+	if (!is_early)
+		kgdbts_break_test();
+}
+
+static void run_breakpoint_test(int is_hw_breakpoint)
+{
+	test_complete = 0;
+	init_simple_test();
+	if (is_hw_breakpoint) {
+		ts.tst = hw_breakpoint_test;
+		ts.name = "hw_breakpoint_test";
+	} else {
+		ts.tst = sw_breakpoint_test;
+		ts.name = "sw_breakpoint_test";
+	}
+	/* Activate test with initial breakpoint */
+	kgdb_breakpoint();
+	/* run code with the break point in it */
+	kgdbts_break_test();
+	kgdb_breakpoint();
+
+	if (test_complete)
+		return;
+
+	eprintk("kgdbts: ERROR %s test failed\n", ts.name);
+	if (is_hw_breakpoint)
+		hwbreaks_ok = 0;
+}
+
+static void run_hw_break_test(int is_write_test)
+{
+	test_complete = 0;
+	init_simple_test();
+	if (is_write_test) {
+		ts.tst = hw_write_break_test;
+		ts.name = "hw_write_break_test";
+	} else {
+		ts.tst = hw_access_break_test;
+		ts.name = "hw_access_break_test";
+	}
+	/* Activate test with initial breakpoint */
+	kgdb_breakpoint();
+	hw_break_val_access();
+	if (is_write_test) {
+		if (test_complete == 2) {
+			eprintk("kgdbts: ERROR %s broke on access\n",
+				ts.name);
+			hwbreaks_ok = 0;
+		}
+		hw_break_val_write();
+	}
+	kgdb_breakpoint();
+
+	if (test_complete == 1)
+		return;
+
+	eprintk("kgdbts: ERROR %s test failed\n", ts.name);
+	hwbreaks_ok = 0;
+}
+
+static void run_nmi_sleep_test(int nmi_sleep)
+{
+	unsigned long flags;
+
+	init_simple_test();
+	ts.tst = nmi_sleep_test;
+	ts.name = "nmi_sleep_test";
+	/* Activate test with initial breakpoint */
+	kgdb_breakpoint();
+	local_irq_save(flags);
+	mdelay(nmi_sleep*1000);
+	touch_nmi_watchdog();
+	local_irq_restore(flags);
+	if (test_complete != 2)
+		eprintk("kgdbts: ERROR nmi_test did not hit nmi\n");
+	kgdb_breakpoint();
+	if (test_complete == 1)
+		return;
+
+	eprintk("kgdbts: ERROR %s test failed\n", ts.name);
+}
+
+static void run_bad_read_test(void)
+{
+	init_simple_test();
+	ts.tst = bad_read_test;
+	ts.name = "bad_read_test";
+	/* Activate test with initial breakpoint */
+	kgdb_breakpoint();
+}
+
+static void run_kernel_clone_test(void)
+{
+	init_simple_test();
+	ts.tst = do_kernel_clone_test;
+	ts.name = "do_kernel_clone_test";
+	/* Activate test with initial breakpoint */
+	kgdb_breakpoint();
+}
+
+static void run_sys_open_test(void)
+{
+	init_simple_test();
+	ts.tst = sys_open_test;
+	ts.name = "sys_open_test";
+	/* Activate test with initial breakpoint */
+	kgdb_breakpoint();
+}
+
+static void run_singlestep_break_test(void)
+{
+	init_simple_test();
+	ts.tst = singlestep_break_test;
+	ts.name = "singlestep_breakpoint_test";
+	/* Activate test with initial breakpoint */
+	kgdb_breakpoint();
+	kgdbts_break_test();
+	kgdbts_break_test();
+}
+
+static void kgdbts_run_tests(void)
+{
+	char *ptr;
+	int clone_test = 0;
+	int do_sys_open_test = 0;
+	int sstep_test = 1000;
+	int nmi_sleep = 0;
+	int i;
+
+	verbose = 0;
+	if (strstr(config, "V1"))
+		verbose = 1;
+	if (strstr(config, "V2"))
+		verbose = 2;
+
+	ptr = strchr(config, 'F');
+	if (ptr)
+		clone_test = simple_strtol(ptr + 1, NULL, 10);
+	ptr = strchr(config, 'S');
+	if (ptr)
+		do_sys_open_test = simple_strtol(ptr + 1, NULL, 10);
+	ptr = strchr(config, 'N');
+	if (ptr)
+		nmi_sleep = simple_strtol(ptr+1, NULL, 10);
+	ptr = strchr(config, 'I');
+	if (ptr)
+		sstep_test = simple_strtol(ptr+1, NULL, 10);
+
+	/* All HW break point tests */
+	if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT) {
+		hwbreaks_ok = 1;
+		v1printk("kgdbts:RUN hw breakpoint test\n");
+		run_breakpoint_test(1);
+		v1printk("kgdbts:RUN hw write breakpoint test\n");
+		run_hw_break_test(1);
+		v1printk("kgdbts:RUN access write breakpoint test\n");
+		run_hw_break_test(0);
+	}
+
+	/* required internal KGDB tests */
+	v1printk("kgdbts:RUN plant and detach test\n");
+	run_plant_and_detach_test(0);
+	v1printk("kgdbts:RUN sw breakpoint test\n");
+	run_breakpoint_test(0);
+	v1printk("kgdbts:RUN bad memory access test\n");
+	run_bad_read_test();
+	v1printk("kgdbts:RUN singlestep test %i iterations\n", sstep_test);
+	for (i = 0; i < sstep_test; i++) {
+		run_singlestep_break_test();
+		if (i % 100 == 0)
+			v1printk("kgdbts:RUN singlestep [%i/%i]\n",
+				 i, sstep_test);
+	}
+
+	/* ===Optional tests=== */
+
+	if (nmi_sleep) {
+		v1printk("kgdbts:RUN NMI sleep %i seconds test\n", nmi_sleep);
+		run_nmi_sleep_test(nmi_sleep);
+	}
+
+	/* If the kernel_clone test is run it will be the last test that is
+	 * executed because a kernel thread will be spawned at the very
+	 * end to unregister the debug hooks.
+	 */
+	if (clone_test) {
+		repeat_test = clone_test;
+		printk(KERN_INFO "kgdbts:RUN kernel_clone for %i breakpoints\n",
+			repeat_test);
+		kthread_run(kgdbts_unreg_thread, NULL, "kgdbts_unreg");
+		run_kernel_clone_test();
+		return;
+	}
+
+	/* If the sys_open test is run it will be the last test that is
+	 * executed because a kernel thread will be spawned at the very
+	 * end to unregister the debug hooks.
+	 */
+	if (do_sys_open_test) {
+		repeat_test = do_sys_open_test;
+		printk(KERN_INFO "kgdbts:RUN sys_open for %i breakpoints\n",
+			repeat_test);
+		kthread_run(kgdbts_unreg_thread, NULL, "kgdbts_unreg");
+		run_sys_open_test();
+		return;
+	}
+	/* Shutdown and unregister */
+	kgdb_unregister_io_module(&kgdbts_io_ops);
+	configured = 0;
+}
+
+static int kgdbts_option_setup(char *opt)
+{
+	if (strlen(opt) >= MAX_CONFIG_LEN) {
+		printk(KERN_ERR "kgdbts: config string too long\n");
+		return 1;
+	}
+	strcpy(config, opt);
+	return 1;
+}
+
+__setup("kgdbts=", kgdbts_option_setup);
+
+static int configure_kgdbts(void)
+{
+	int err = 0;
+
+	if (!strlen(config) || isspace(config[0]))
+		goto noconfig;
+
+	final_ack = 0;
+	run_plant_and_detach_test(1);
+
+	err = kgdb_register_io_module(&kgdbts_io_ops);
+	if (err) {
+		configured = 0;
+		return err;
+	}
+	configured = 1;
+	kgdbts_run_tests();
+
+	return err;
+
+noconfig:
+	config[0] = 0;
+	configured = 0;
+
+	return err;
+}
+
+static int __init init_kgdbts(void)
+{
+	/* Already configured? */
+	if (configured == 1)
+		return 0;
+
+	return configure_kgdbts();
+}
+device_initcall(init_kgdbts);
+
+static int kgdbts_get_char(void)
+{
+	int val = 0;
+
+	if (ts.run_test)
+		val = ts.run_test(1, 0);
+
+	return val;
+}
+
+static void kgdbts_put_char(u8 chr)
+{
+	if (ts.run_test)
+		ts.run_test(0, chr);
+}
+
+static int param_set_kgdbts_var(const char *kmessage,
+				const struct kernel_param *kp)
+{
+	size_t len = strlen(kmessage);
+
+	if (len >= MAX_CONFIG_LEN) {
+		printk(KERN_ERR "kgdbts: config string too long\n");
+		return -ENOSPC;
+	}
+
+	/* Only copy in the string if the init function has not run yet */
+	if (configured < 0) {
+		strcpy(config, kmessage);
+		return 0;
+	}
+
+	if (configured == 1) {
+		printk(KERN_ERR "kgdbts: ERROR: Already configured and running.\n");
+		return -EBUSY;
+	}
+
+	strcpy(config, kmessage);
+	/* Chop out \n char as a result of echo */
+	if (len && config[len - 1] == '\n')
+		config[len - 1] = '\0';
+
+	/* Go and configure with the new params. */
+	return configure_kgdbts();
+}
+
+static void kgdbts_pre_exp_handler(void)
+{
+	/* Increment the module count when the debugger is active */
+	if (!kgdb_connected)
+		try_module_get(THIS_MODULE);
+}
+
+static void kgdbts_post_exp_handler(void)
+{
+	/* decrement the module count when the debugger detaches */
+	if (!kgdb_connected)
+		module_put(THIS_MODULE);
+}
+
+static struct kgdb_io kgdbts_io_ops = {
+	.name			= "kgdbts",
+	.read_char		= kgdbts_get_char,
+	.write_char		= kgdbts_put_char,
+	.pre_exception		= kgdbts_pre_exp_handler,
+	.post_exception		= kgdbts_post_exp_handler,
+};
+
+/*
+ * not really modular, but the easiest way to keep compat with existing
+ * bootargs behaviour is to continue using module_param here.
+ */
+module_param_call(kgdbts, param_set_kgdbts_var, param_get_string, &kps, 0644);
+MODULE_PARM_DESC(kgdbts, "<A|V1|V2>[F#|S#][N#]");