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-rw-r--r--arch/x86/kernel/kprobes/core.c20
-rw-r--r--kernel/trace/ftrace.c53
-rw-r--r--kernel/trace/trace.c1
-rw-r--r--kernel/trace/trace_events.c69
4 files changed, 115 insertions, 28 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index f7e3cd50ece..98f654d466e 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -1020,6 +1020,15 @@ int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
regs->flags &= ~X86_EFLAGS_IF;
trace_hardirqs_off();
regs->ip = (unsigned long)(jp->entry);
+
+ /*
+ * jprobes use jprobe_return() which skips the normal return
+ * path of the function, and this messes up the accounting of the
+ * function graph tracer to get messed up.
+ *
+ * Pause function graph tracing while performing the jprobe function.
+ */
+ pause_graph_tracing();
return 1;
}
NOKPROBE_SYMBOL(setjmp_pre_handler);
@@ -1048,24 +1057,25 @@ int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
u8 *addr = (u8 *) (regs->ip - 1);
struct jprobe *jp = container_of(p, struct jprobe, kp);
+ void *saved_sp = kcb->jprobe_saved_sp;
if ((addr > (u8 *) jprobe_return) &&
(addr < (u8 *) jprobe_return_end)) {
- if (stack_addr(regs) != kcb->jprobe_saved_sp) {
+ if (stack_addr(regs) != saved_sp) {
struct pt_regs *saved_regs = &kcb->jprobe_saved_regs;
printk(KERN_ERR
"current sp %p does not match saved sp %p\n",
- stack_addr(regs), kcb->jprobe_saved_sp);
+ stack_addr(regs), saved_sp);
printk(KERN_ERR "Saved registers for jprobe %p\n", jp);
show_regs(saved_regs);
printk(KERN_ERR "Current registers\n");
show_regs(regs);
BUG();
}
+ /* It's OK to start function graph tracing again */
+ unpause_graph_tracing();
*regs = kcb->jprobe_saved_regs;
- memcpy((kprobe_opcode_t *)(kcb->jprobe_saved_sp),
- kcb->jprobes_stack,
- MIN_STACK_SIZE(kcb->jprobe_saved_sp));
+ memcpy(saved_sp, kcb->jprobes_stack, MIN_STACK_SIZE(saved_sp));
preempt_enable_no_resched();
return 1;
}
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 929a733d302..224e768bdc7 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2497,12 +2497,14 @@ static void ftrace_run_update_code(int command)
}
static void ftrace_run_modify_code(struct ftrace_ops *ops, int command,
- struct ftrace_hash *old_hash)
+ struct ftrace_ops_hash *old_hash)
{
ops->flags |= FTRACE_OPS_FL_MODIFYING;
- ops->old_hash.filter_hash = old_hash;
+ ops->old_hash.filter_hash = old_hash->filter_hash;
+ ops->old_hash.notrace_hash = old_hash->notrace_hash;
ftrace_run_update_code(command);
ops->old_hash.filter_hash = NULL;
+ ops->old_hash.notrace_hash = NULL;
ops->flags &= ~FTRACE_OPS_FL_MODIFYING;
}
@@ -3579,7 +3581,7 @@ static struct ftrace_ops trace_probe_ops __read_mostly =
static int ftrace_probe_registered;
-static void __enable_ftrace_function_probe(struct ftrace_hash *old_hash)
+static void __enable_ftrace_function_probe(struct ftrace_ops_hash *old_hash)
{
int ret;
int i;
@@ -3637,6 +3639,7 @@ int
register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
void *data)
{
+ struct ftrace_ops_hash old_hash_ops;
struct ftrace_func_probe *entry;
struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash;
struct ftrace_hash *old_hash = *orig_hash;
@@ -3658,6 +3661,10 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
mutex_lock(&trace_probe_ops.func_hash->regex_lock);
+ old_hash_ops.filter_hash = old_hash;
+ /* Probes only have filters */
+ old_hash_ops.notrace_hash = NULL;
+
hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash);
if (!hash) {
count = -ENOMEM;
@@ -3718,7 +3725,7 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
- __enable_ftrace_function_probe(old_hash);
+ __enable_ftrace_function_probe(&old_hash_ops);
if (!ret)
free_ftrace_hash_rcu(old_hash);
@@ -4006,10 +4013,34 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
}
static void ftrace_ops_update_code(struct ftrace_ops *ops,
- struct ftrace_hash *old_hash)
+ struct ftrace_ops_hash *old_hash)
{
- if (ops->flags & FTRACE_OPS_FL_ENABLED && ftrace_enabled)
+ struct ftrace_ops *op;
+
+ if (!ftrace_enabled)
+ return;
+
+ if (ops->flags & FTRACE_OPS_FL_ENABLED) {
ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash);
+ return;
+ }
+
+ /*
+ * If this is the shared global_ops filter, then we need to
+ * check if there is another ops that shares it, is enabled.
+ * If so, we still need to run the modify code.
+ */
+ if (ops->func_hash != &global_ops.local_hash)
+ return;
+
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ if (op->func_hash == &global_ops.local_hash &&
+ op->flags & FTRACE_OPS_FL_ENABLED) {
+ ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash);
+ /* Only need to do this once */
+ return;
+ }
+ } while_for_each_ftrace_op(op);
}
static int
@@ -4017,6 +4048,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
unsigned long ip, int remove, int reset, int enable)
{
struct ftrace_hash **orig_hash;
+ struct ftrace_ops_hash old_hash_ops;
struct ftrace_hash *old_hash;
struct ftrace_hash *hash;
int ret;
@@ -4053,9 +4085,11 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
mutex_lock(&ftrace_lock);
old_hash = *orig_hash;
+ old_hash_ops.filter_hash = ops->func_hash->filter_hash;
+ old_hash_ops.notrace_hash = ops->func_hash->notrace_hash;
ret = ftrace_hash_move(ops, enable, orig_hash, hash);
if (!ret) {
- ftrace_ops_update_code(ops, old_hash);
+ ftrace_ops_update_code(ops, &old_hash_ops);
free_ftrace_hash_rcu(old_hash);
}
mutex_unlock(&ftrace_lock);
@@ -4267,6 +4301,7 @@ static void __init set_ftrace_early_filters(void)
int ftrace_regex_release(struct inode *inode, struct file *file)
{
struct seq_file *m = (struct seq_file *)file->private_data;
+ struct ftrace_ops_hash old_hash_ops;
struct ftrace_iterator *iter;
struct ftrace_hash **orig_hash;
struct ftrace_hash *old_hash;
@@ -4300,10 +4335,12 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
mutex_lock(&ftrace_lock);
old_hash = *orig_hash;
+ old_hash_ops.filter_hash = iter->ops->func_hash->filter_hash;
+ old_hash_ops.notrace_hash = iter->ops->func_hash->notrace_hash;
ret = ftrace_hash_move(iter->ops, filter_hash,
orig_hash, iter->hash);
if (!ret) {
- ftrace_ops_update_code(iter->ops, old_hash);
+ ftrace_ops_update_code(iter->ops, &old_hash_ops);
free_ftrace_hash_rcu(old_hash);
}
mutex_unlock(&ftrace_lock);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2e767972e99..4a9079b9f08 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6918,7 +6918,6 @@ void __init trace_init(void)
tracepoint_printk = 0;
}
tracer_alloc_buffers();
- init_ftrace_syscalls();
trace_event_init();
}
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 366a78a3e61..b03a0ea77b9 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2429,12 +2429,39 @@ static __init int event_trace_memsetup(void)
return 0;
}
+static __init void
+early_enable_events(struct trace_array *tr, bool disable_first)
+{
+ char *buf = bootup_event_buf;
+ char *token;
+ int ret;
+
+ while (true) {
+ token = strsep(&buf, ",");
+
+ if (!token)
+ break;
+ if (!*token)
+ continue;
+
+ /* Restarting syscalls requires that we stop them first */
+ if (disable_first)
+ ftrace_set_clr_event(tr, token, 0);
+
+ ret = ftrace_set_clr_event(tr, token, 1);
+ if (ret)
+ pr_warn("Failed to enable trace event: %s\n", token);
+
+ /* Put back the comma to allow this to be called again */
+ if (buf)
+ *(buf - 1) = ',';
+ }
+}
+
static __init int event_trace_enable(void)
{
struct trace_array *tr = top_trace_array();
struct ftrace_event_call **iter, *call;
- char *buf = bootup_event_buf;
- char *token;
int ret;
if (!tr)
@@ -2456,18 +2483,7 @@ static __init int event_trace_enable(void)
*/
__trace_early_add_events(tr);
- while (true) {
- token = strsep(&buf, ",");
-
- if (!token)
- break;
- if (!*token)
- continue;
-
- ret = ftrace_set_clr_event(tr, token, 1);
- if (ret)
- pr_warn("Failed to enable trace event: %s\n", token);
- }
+ early_enable_events(tr, false);
trace_printk_start_comm();
@@ -2478,6 +2494,31 @@ static __init int event_trace_enable(void)
return 0;
}
+/*
+ * event_trace_enable() is called from trace_event_init() first to
+ * initialize events and perhaps start any events that are on the
+ * command line. Unfortunately, there are some events that will not
+ * start this early, like the system call tracepoints that need
+ * to set the TIF_SYSCALL_TRACEPOINT flag of pid 1. But event_trace_enable()
+ * is called before pid 1 starts, and this flag is never set, making
+ * the syscall tracepoint never get reached, but the event is enabled
+ * regardless (and not doing anything).
+ */
+static __init int event_trace_enable_again(void)
+{
+ struct trace_array *tr;
+
+ tr = top_trace_array();
+ if (!tr)
+ return -ENODEV;
+
+ early_enable_events(tr, true);
+
+ return 0;
+}
+
+early_initcall(event_trace_enable_again);
+
static __init int event_trace_init(void)
{
struct trace_array *tr;
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-11 07:05:01 +0000