X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Fkgdb.c;h=e4dcfb2272a4184b19903927b1c438169788461a;hb=6a7c7eaf71b636f197d73b381a2ab729ebdcfb2e;hp=017ee782bc088861129e60ef29587257883d9fc7;hpb=dc7d552705215ac50a0617fcf51bb9c736255b8e;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/kgdb.c b/kernel/kgdb.c index 017ee78..e4dcfb2 100644 --- a/kernel/kgdb.c +++ b/kernel/kgdb.c @@ -28,6 +28,7 @@ * kind, whether express or implied. */ #include +#include #include #include #include @@ -51,16 +52,19 @@ #include #include #include +#include static int kgdb_break_asap; +#define KGDB_MAX_THREAD_QUERY 17 struct kgdb_state { int ex_vector; int signo; int err_code; int cpu; int pass_exception; - long threadid; + unsigned long thr_query; + unsigned long threadid; long kgdb_usethreadid; struct pt_regs *linux_regs; }; @@ -145,7 +149,7 @@ atomic_t kgdb_cpu_doing_single_step = ATOMIC_INIT(-1); * the other CPUs might interfere with your debugging context, so * use this with care: */ -int kgdb_do_roundup = 1; +static int kgdb_do_roundup = 1; static int __init opt_nokgdbroundup(char *str) { @@ -164,13 +168,6 @@ early_param("nokgdbroundup", opt_nokgdbroundup); * Weak aliases for breakpoint management, * can be overriden by architectures when needed: */ -int __weak kgdb_validate_break_address(unsigned long addr) -{ - char tmp_variable[BREAK_INSTR_SIZE]; - - return probe_kernel_read(tmp_variable, (char *)addr, BREAK_INSTR_SIZE); -} - int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr) { int err; @@ -189,6 +186,25 @@ int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle) (char *)bundle, BREAK_INSTR_SIZE); } +int __weak kgdb_validate_break_address(unsigned long addr) +{ + char tmp_variable[BREAK_INSTR_SIZE]; + int err; + /* Validate setting the breakpoint and then removing it. In the + * remove fails, the kernel needs to emit a bad message because we + * are deep trouble not being able to put things back the way we + * found them. + */ + err = kgdb_arch_set_breakpoint(addr, tmp_variable); + if (err) + return err; + err = kgdb_arch_remove_breakpoint(addr, tmp_variable); + if (err) + printk(KERN_ERR "KGDB: Critical breakpoint error, kernel " + "memory destroyed at: %lx", addr); + return err; +} + unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs) { return instruction_pointer(regs); @@ -199,6 +215,17 @@ int __weak kgdb_arch_init(void) return 0; } +int __weak kgdb_skipexception(int exception, struct pt_regs *regs) +{ + return 0; +} + +void __weak +kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code) +{ + return; +} + /** * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb. * @regs: Current &struct pt_regs. @@ -215,8 +242,6 @@ void __weak kgdb_disable_hw_debug(struct pt_regs *regs) * GDB remote protocol parser: */ -static const char hexchars[] = "0123456789abcdef"; - static int hex(char ch) { if ((ch >= 'a') && (ch <= 'f')) @@ -304,8 +329,8 @@ static void put_packet(char *buffer) } kgdb_io_ops->write_char('#'); - kgdb_io_ops->write_char(hexchars[checksum >> 4]); - kgdb_io_ops->write_char(hexchars[checksum & 0xf]); + kgdb_io_ops->write_char(hex_asc_hi(checksum)); + kgdb_io_ops->write_char(hex_asc_lo(checksum)); if (kgdb_io_ops->flush) kgdb_io_ops->flush(); @@ -334,14 +359,6 @@ static void put_packet(char *buffer) } } -static char *pack_hex_byte(char *pkt, u8 byte) -{ - *pkt++ = hexchars[byte >> 4]; - *pkt++ = hexchars[byte & 0xf]; - - return pkt; -} - /* * Convert the memory pointed to by mem into hex, placing result in buf. * Return a pointer to the last char put in buf (null). May return an error. @@ -426,13 +443,18 @@ int kgdb_hex2mem(char *buf, char *mem, int count) * While we find nice hex chars, build a long_val. * Return number of chars processed. */ -int kgdb_hex2long(char **ptr, long *long_val) +int kgdb_hex2long(char **ptr, unsigned long *long_val) { int hex_val; int num = 0; + int negate = 0; *long_val = 0; + if (**ptr == '-') { + negate = 1; + (*ptr)++; + } while (**ptr) { hex_val = hex(**ptr); if (hex_val < 0) @@ -443,6 +465,9 @@ int kgdb_hex2long(char **ptr, long *long_val) (*ptr)++; } + if (negate) + *long_val = -*long_val; + return num; } @@ -463,7 +488,7 @@ static int write_mem_msg(int binary) if (err) return err; if (CACHE_FLUSH_IS_SAFE) - flush_icache_range(addr, addr + length + 1); + flush_icache_range(addr, addr + length); return 0; } @@ -474,8 +499,8 @@ static void error_packet(char *pkt, int error) { error = -error; pkt[0] = 'E'; - pkt[1] = hexchars[(error / 10)]; - pkt[2] = hexchars[(error % 10)]; + pkt[1] = hex_asc[(error / 10)]; + pkt[2] = hex_asc[(error % 10)]; pkt[3] = '\0'; } @@ -506,19 +531,22 @@ static void int_to_threadref(unsigned char *id, int value) scan = (unsigned char *)id; while (i--) *scan++ = 0; - *scan++ = (value >> 24) & 0xff; - *scan++ = (value >> 16) & 0xff; - *scan++ = (value >> 8) & 0xff; - *scan++ = (value & 0xff); + put_unaligned_be32(value, scan); } static struct task_struct *getthread(struct pt_regs *regs, int tid) { /* - * Non-positive TIDs are remapped idle tasks: + * Non-positive TIDs are remapped to the cpu shadow information */ - if (tid <= 0) - return idle_task(-tid); + if (tid == 0 || tid == -1) + tid = -atomic_read(&kgdb_active) - 2; + if (tid < 0) { + if (kgdb_info[-tid - 2].task) + return kgdb_info[-tid - 2].task; + else + return idle_task(-tid - 2); + } /* * find_task_by_pid_ns() does not take the tasklist lock anymore @@ -549,18 +577,6 @@ static void kgdb_wait(struct pt_regs *regs) smp_wmb(); atomic_set(&cpu_in_kgdb[cpu], 1); - /* - * The primary CPU must be active to enter here, but this is - * guard in case the primary CPU had not been selected if - * this was an entry via nmi. - */ - while (atomic_read(&kgdb_active) == -1) - cpu_relax(); - - /* Wait till primary CPU goes completely into the debugger. */ - while (!atomic_read(&cpu_in_kgdb[atomic_read(&kgdb_active)])) - cpu_relax(); - /* Wait till primary CPU is done with debugging */ while (atomic_read(&passive_cpu_wait[cpu])) cpu_relax(); @@ -574,6 +590,8 @@ static void kgdb_wait(struct pt_regs *regs) /* Signal the primary CPU that we are done: */ atomic_set(&cpu_in_kgdb[cpu], 0); + touch_softlockup_watchdog(); + clocksource_touch_watchdog(); local_irq_restore(flags); } #endif @@ -587,12 +605,12 @@ static void kgdb_flush_swbreak_addr(unsigned long addr) if (!CACHE_FLUSH_IS_SAFE) return; - if (current->mm) { + if (current->mm && current->mm->mmap_cache) { flush_cache_range(current->mm->mmap_cache, addr, addr + BREAK_INSTR_SIZE); - } else { - flush_icache_range(addr, addr + BREAK_INSTR_SIZE); } + /* Force flush instruction cache if it was outside the mm */ + flush_icache_range(addr, addr + BREAK_INSTR_SIZE); } /* @@ -708,7 +726,7 @@ int kgdb_isremovedbreak(unsigned long addr) return 0; } -int remove_all_break(void) +static int remove_all_break(void) { unsigned long addr; int error; @@ -716,14 +734,16 @@ int remove_all_break(void) /* Clear memory breakpoints. */ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) { - if (kgdb_break[i].state != BP_SET) - continue; + if (kgdb_break[i].state != BP_ACTIVE) + goto setundefined; addr = kgdb_break[i].bpt_addr; error = kgdb_arch_remove_breakpoint(addr, kgdb_break[i].saved_instr); if (error) - return error; - kgdb_break[i].state = BP_REMOVED; + printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n", + addr); +setundefined: + kgdb_break[i].state = BP_UNDEFINED; } /* Clear hardware breakpoints. */ @@ -734,14 +754,15 @@ int remove_all_break(void) } /* - * Remap normal tasks to their real PID, idle tasks to -1 ... -NR_CPUs: + * Remap normal tasks to their real PID, + * CPU shadow threads are mapped to -CPU - 2 */ static inline int shadow_pid(int realpid) { if (realpid) return realpid; - return -1-raw_smp_processor_id(); + return -raw_smp_processor_id() - 2; } static char gdbmsgbuf[BUFMAX + 1]; @@ -835,7 +856,7 @@ static void gdb_cmd_getregs(struct kgdb_state *ks) local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo; } else { local_debuggerinfo = NULL; - for (i = 0; i < NR_CPUS; i++) { + for_each_online_cpu(i) { /* * Try to find the task on some other * or possibly this node if we do not @@ -969,10 +990,13 @@ static int gdb_cmd_reboot(struct kgdb_state *ks) /* Handle the 'q' query packets */ static void gdb_cmd_query(struct kgdb_state *ks) { - struct task_struct *thread; + struct task_struct *g; + struct task_struct *p; unsigned char thref[8]; char *ptr; int i; + int cpu; + int finished = 0; switch (remcom_in_buffer[1]) { case 's': @@ -982,22 +1006,34 @@ static void gdb_cmd_query(struct kgdb_state *ks) break; } - if (remcom_in_buffer[1] == 'f') - ks->threadid = 1; - + i = 0; remcom_out_buffer[0] = 'm'; ptr = remcom_out_buffer + 1; - - for (i = 0; i < 17; ks->threadid++) { - thread = getthread(ks->linux_regs, ks->threadid); - if (thread) { - int_to_threadref(thref, ks->threadid); + if (remcom_in_buffer[1] == 'f') { + /* Each cpu is a shadow thread */ + for_each_online_cpu(cpu) { + ks->thr_query = 0; + int_to_threadref(thref, -cpu - 2); pack_threadid(ptr, thref); ptr += BUF_THREAD_ID_SIZE; *(ptr++) = ','; i++; } } + + do_each_thread(g, p) { + if (i >= ks->thr_query && !finished) { + int_to_threadref(thref, p->pid); + pack_threadid(ptr, thref); + ptr += BUF_THREAD_ID_SIZE; + *(ptr++) = ','; + ks->thr_query++; + if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0) + finished = 1; + } + i++; + } while_each_thread(g, p); + *(--ptr) = '\0'; break; @@ -1020,15 +1056,15 @@ static void gdb_cmd_query(struct kgdb_state *ks) error_packet(remcom_out_buffer, -EINVAL); break; } - if (ks->threadid > 0) { + if ((int)ks->threadid > 0) { kgdb_mem2hex(getthread(ks->linux_regs, ks->threadid)->comm, remcom_out_buffer, 16); } else { static char tmpstr[23 + BUF_THREAD_ID_SIZE]; - sprintf(tmpstr, "Shadow task %d for pid 0", - (int)(-ks->threadid-1)); + sprintf(tmpstr, "shadowCPU%d", + (int)(-ks->threadid - 2)); kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr)); } break; @@ -1137,10 +1173,10 @@ static void gdb_cmd_break(struct kgdb_state *ks) error = kgdb_remove_sw_break(addr); else if (remcom_in_buffer[0] == 'Z') error = arch_kgdb_ops.set_hw_breakpoint(addr, - (int)length, *bpt_type); + (int)length, *bpt_type - '0'); else if (remcom_in_buffer[0] == 'z') error = arch_kgdb_ops.remove_hw_breakpoint(addr, - (int) length, *bpt_type); + (int) length, *bpt_type - '0'); if (error == 0) strcpy(remcom_out_buffer, "OK"); @@ -1325,7 +1361,8 @@ static int kgdb_reenter_check(struct kgdb_state *ks) exception_level = 0; kgdb_skipexception(ks->ex_vector, ks->linux_regs); kgdb_activate_sw_breakpoints(); - printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed\n"); + printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed %lx\n", + addr); WARN_ON_ONCE(1); return 1; @@ -1396,6 +1433,8 @@ acquirelock: atomic_read(&kgdb_cpu_doing_single_step) != cpu) { atomic_set(&kgdb_active, -1); + touch_softlockup_watchdog(); + clocksource_touch_watchdog(); local_irq_restore(flags); goto acquirelock; @@ -1425,23 +1464,23 @@ acquirelock: * Get the passive CPU lock which will hold all the non-primary * CPU in a spin state while the debugger is active */ - if (!kgdb_single_step || !kgdb_contthread) { + if (!kgdb_single_step) { for (i = 0; i < NR_CPUS; i++) atomic_set(&passive_cpu_wait[i], 1); } -#ifdef CONFIG_SMP - /* Signal the other CPUs to enter kgdb_wait() */ - if ((!kgdb_single_step || !kgdb_contthread) && kgdb_do_roundup) - kgdb_roundup_cpus(flags); -#endif - /* * spin_lock code is good enough as a barrier so we don't * need one here: */ atomic_set(&cpu_in_kgdb[ks->cpu], 1); +#ifdef CONFIG_SMP + /* Signal the other CPUs to enter kgdb_wait() */ + if ((!kgdb_single_step) && kgdb_do_roundup) + kgdb_roundup_cpus(flags); +#endif + /* * Wait for the other CPUs to be notified and be waiting for us: */ @@ -1457,7 +1496,7 @@ acquirelock: kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code); kgdb_deactivate_sw_breakpoints(); kgdb_single_step = 0; - kgdb_contthread = NULL; + kgdb_contthread = current; exception_level = 0; /* Talk to debugger with gdbserial protocol */ @@ -1471,7 +1510,7 @@ acquirelock: kgdb_info[ks->cpu].task = NULL; atomic_set(&cpu_in_kgdb[ks->cpu], 0); - if (!kgdb_single_step || !kgdb_contthread) { + if (!kgdb_single_step) { for (i = NR_CPUS-1; i >= 0; i--) atomic_set(&passive_cpu_wait[i], 0); /* @@ -1487,6 +1526,8 @@ acquirelock: kgdb_restore: /* Free kgdb_active */ atomic_set(&kgdb_active, -1); + touch_softlockup_watchdog(); + clocksource_touch_watchdog(); local_irq_restore(flags); return error; @@ -1496,7 +1537,8 @@ int kgdb_nmicallback(int cpu, void *regs) { #ifdef CONFIG_SMP if (!atomic_read(&cpu_in_kgdb[cpu]) && - atomic_read(&kgdb_active) != cpu) { + atomic_read(&kgdb_active) != cpu && + atomic_read(&cpu_in_kgdb[atomic_read(&kgdb_active)])) { kgdb_wait((struct pt_regs *)regs); return 0; } @@ -1504,7 +1546,8 @@ int kgdb_nmicallback(int cpu, void *regs) return 1; } -void kgdb_console_write(struct console *co, const char *s, unsigned count) +static void kgdb_console_write(struct console *co, const char *s, + unsigned count) { unsigned long flags; @@ -1589,7 +1632,7 @@ static void kgdb_initial_breakpoint(void) } /** - * kkgdb_register_io_module - register KGDB IO module + * kgdb_register_io_module - register KGDB IO module * @new_kgdb_io_ops: the io ops vector * * Register it with the KGDB core.