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Diffstat (limited to 'drivers/misc/kgdbts.c')
| -rw-r--r-- | drivers/misc/kgdbts.c | 1191 |
1 files changed, 1191 insertions, 0 deletions
diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c new file mode 100644 index 0000000000..88b91ad8e5 --- /dev/null +++ b/drivers/misc/kgdbts.c @@ -0,0 +1,1191 @@ +// 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 <linux/kallsyms.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"); +} + +/* + * This is a cached wrapper for kallsyms_lookup_name(). + * + * The cache is a big win for several tests. For example it more the doubles + * the cycles per second during the sys_open test. This is not theoretic, + * the performance improvement shows up at human scale, especially when + * testing using emulators. + * + * Obviously neither re-entrant nor thread-safe but that is OK since it + * can only be called from the debug trap (and therefore all other CPUs + * are halted). + */ +static unsigned long lookup_addr(char *arg) +{ + static char cached_arg[KSYM_NAME_LEN]; + static unsigned long cached_addr; + + if (strcmp(arg, cached_arg)) { + strscpy(cached_arg, arg, KSYM_NAME_LEN); + cached_addr = kallsyms_lookup_name(arg); + } + + return (unsigned long)dereference_function_descriptor( + (void *)cached_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, "do_sys_openat2") || !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 */ + { "do_sys_openat2", "OK", sw_break, }, /* set sw breakpoint */ + { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */ + { "do_sys_openat2", "OK", sw_rem_break }, /*remove breakpoint */ + { "g", "do_sys_openat2", 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", "do_sys_openat2", NULL, check_single_step }, + { "do_sys_openat2", "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#]"); |