diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index b3a36b0cfc81a3742b9c588b0efa8bb1b9ec8389..1883a4a9f16a7fc70bf533cd2206d046c6722b14 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -266,7 +266,7 @@ extern void kprobes_inc_nmissed_count(struct kprobe *p); extern bool arch_within_kprobe_blacklist(unsigned long addr); extern int arch_populate_kprobe_blacklist(void); extern bool arch_kprobe_on_func_entry(unsigned long offset); -extern bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset); +extern int kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset); extern bool within_kprobe_blacklist(unsigned long addr); extern int kprobe_add_ksym_blacklist(unsigned long entry); diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 0f21617f1a6689395d9caa86d8d2982ef9a3ea84..966ed898032746b58ad79caead930f66292a9148 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -307,11 +307,13 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) \ it_func_ptr = \ rcu_dereference_raw((&__tracepoint_##_name)->funcs); \ - do { \ - it_func = (it_func_ptr)->func; \ - __data = (it_func_ptr)->data; \ - ((void(*)(void *, proto))(it_func))(__data, args); \ - } while ((++it_func_ptr)->func); \ + if (it_func_ptr) { \ + do { \ + it_func = (it_func_ptr)->func; \ + __data = (it_func_ptr)->data; \ + ((void(*)(void *, proto))(it_func))(__data, args); \ + } while ((++it_func_ptr)->func); \ + } \ return 0; \ } \ DEFINE_STATIC_CALL(tp_func_##_name, __traceiter_##_name); diff --git a/init/init_task.c b/init/init_task.c index 8a992d73e6fb7027e0b7b642b3935d81cb518fec..3711cdaafed2fb47ea655f98dd860c588d10fe1e 100644 --- a/init/init_task.c +++ b/init/init_task.c @@ -198,7 +198,8 @@ struct task_struct init_task .lockdep_recursion = 0, #endif #ifdef CONFIG_FUNCTION_GRAPH_TRACER - .ret_stack = NULL, + .ret_stack = NULL, + .tracing_graph_pause = ATOMIC_INIT(0), #endif #if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPTION) .trace_recursion = 0, diff --git a/kernel/kprobes.c b/kernel/kprobes.c index f7fb5d135930fa46e8f57a85ce67b856a6e23347..d5a3eb74a6574aade1fb23c3959a7ababee96d66 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1954,28 +1954,48 @@ bool __weak arch_kprobe_on_func_entry(unsigned long offset) return !offset; } -bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset) +/** + * kprobe_on_func_entry() -- check whether given address is function entry + * @addr: Target address + * @sym: Target symbol name + * @offset: The offset from the symbol or the address + * + * This checks whether the given @addr+@offset or @sym+@offset is on the + * function entry address or not. + * This returns 0 if it is the function entry, or -EINVAL if it is not. + * And also it returns -ENOENT if it fails the symbol or address lookup. + * Caller must pass @addr or @sym (either one must be NULL), or this + * returns -EINVAL. + */ +int kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset) { kprobe_opcode_t *kp_addr = _kprobe_addr(addr, sym, offset); if (IS_ERR(kp_addr)) - return false; + return PTR_ERR(kp_addr); - if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset) || - !arch_kprobe_on_func_entry(offset)) - return false; + if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset)) + return -ENOENT; - return true; + if (!arch_kprobe_on_func_entry(offset)) + return -EINVAL; + + return 0; } int register_kretprobe(struct kretprobe *rp) { - int ret = 0; + int ret; struct kretprobe_instance *inst; int i; void *addr; - if (!kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset)) + ret = kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset); + if (ret) + return ret; + + /* If only rp->kp.addr is specified, check reregistering kprobes */ + if (rp->kp.addr && check_kprobe_rereg(&rp->kp)) return -EINVAL; if (kretprobe_blacklist_size) { diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index 73edb9e4f3548e0331ea0d38c351750a05a418d9..29a6ebeebc9e1eb75f803046c92cb7fef97c418d 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -394,7 +394,6 @@ static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) } if (t->ret_stack == NULL) { - atomic_set(&t->tracing_graph_pause, 0); atomic_set(&t->trace_overrun, 0); t->curr_ret_stack = -1; t->curr_ret_depth = -1; @@ -489,7 +488,6 @@ static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); static void graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) { - atomic_set(&t->tracing_graph_pause, 0); atomic_set(&t->trace_overrun, 0); t->ftrace_timestamp = 0; /* make curr_ret_stack visible before we add the ret_stack */ diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index d06aab4dcbb8f41fe9929197b509bfad94f6e99b..6756379b661fee56125f1ea81e8106ddbb1f6887 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -562,6 +562,8 @@ static int __irqsoff_tracer_init(struct trace_array *tr) /* non overwrite screws up the latency tracers */ set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1); set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1); + /* without pause, we will produce garbage if another latency occurs */ + set_tracer_flag(tr, TRACE_ITER_PAUSE_ON_TRACE, 1); tr->max_latency = 0; irqsoff_trace = tr; @@ -583,11 +585,13 @@ static void __irqsoff_tracer_reset(struct trace_array *tr) { int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT; int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE; + int pause_flag = save_flags & TRACE_ITER_PAUSE_ON_TRACE; stop_irqsoff_tracer(tr, is_graph(tr)); set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag); set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag); + set_tracer_flag(tr, TRACE_ITER_PAUSE_ON_TRACE, pause_flag); ftrace_reset_array_ops(tr); irqsoff_busy = false; diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index e6fba1798771b401eaf97d08b2c4d5926eb81995..56c7fbff7bd7f7186bef4f9a5506063767b578aa 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -221,9 +221,9 @@ bool trace_kprobe_on_func_entry(struct trace_event_call *call) { struct trace_kprobe *tk = trace_kprobe_primary_from_call(call); - return tk ? kprobe_on_func_entry(tk->rp.kp.addr, + return tk ? (kprobe_on_func_entry(tk->rp.kp.addr, tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name, - tk->rp.kp.addr ? 0 : tk->rp.kp.offset) : false; + tk->rp.kp.addr ? 0 : tk->rp.kp.offset) == 0) : false; } bool trace_kprobe_error_injectable(struct trace_event_call *call) @@ -828,9 +828,11 @@ static int trace_kprobe_create(int argc, const char *argv[]) } if (is_return) flags |= TPARG_FL_RETURN; - if (kprobe_on_func_entry(NULL, symbol, offset)) + ret = kprobe_on_func_entry(NULL, symbol, offset); + if (ret == 0) flags |= TPARG_FL_FENTRY; - if (offset && is_return && !(flags & TPARG_FL_FENTRY)) { + /* Defer the ENOENT case until register kprobe */ + if (ret == -EINVAL && is_return) { trace_probe_log_err(0, BAD_RETPROBE); goto parse_error; }