Merge tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - kprobes: Restructured stack unwinder to show properly on x86 when a
   stack dump happens from a kretprobe callback.

 - Fix to bootconfig parsing

 - Have tracefs allow owner and group permissions by default (only
   denying others). There's been pressure to allow non root to tracefs
   in a controlled fashion, and using groups is probably the safest.

 - Bootconfig memory managament updates.

 - Bootconfig clean up to have the tools directory be less dependent on
   changes in the kernel tree.

 - Allow perf to be traced by function tracer.

 - Rewrite of function graph tracer to be a callback from the function
   tracer instead of having its own trampoline (this change will happen
   on an arch by arch basis, and currently only x86_64 implements it).

 - Allow multiple direct trampolines (bpf hooks to functions) be batched
   together in one synchronization.

 - Allow histogram triggers to add variables that can perform
   calculations against the event's fields.

 - Use the linker to determine architecture callbacks from the ftrace
   trampoline to allow for proper parameter prototypes and prevent
   warnings from the compiler.

 - Extend histogram triggers to key off of variables.

 - Have trace recursion use bit magic to determine preempt context over
   if branches.

 - Have trace recursion disable preemption as all use cases do anyway.

 - Added testing for verification of tracing utilities.

 - Various small clean ups and fixes.

* tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (101 commits)
  tracing/histogram: Fix semicolon.cocci warnings
  tracing/histogram: Fix documentation inline emphasis warning
  tracing: Increase PERF_MAX_TRACE_SIZE to handle Sentinel1 and docker together
  tracing: Show size of requested perf buffer
  bootconfig: Initialize ret in xbc_parse_tree()
  ftrace: do CPU checking after preemption disabled
  ftrace: disable preemption when recursion locked
  tracing/histogram: Document expression arithmetic and constants
  tracing/histogram: Optimize division by a power of 2
  tracing/histogram: Covert expr to const if both operands are constants
  tracing/histogram: Simplify handling of .sym-offset in expressions
  tracing: Fix operator precedence for hist triggers expression
  tracing: Add division and multiplication support for hist triggers
  tracing: Add support for creating hist trigger variables from literal
  selftests/ftrace: Stop tracing while reading the trace file by default
  MAINTAINERS: Update KPROBES and TRACING entries
  test_kprobes: Move it from kernel/ to lib/
  docs, kprobes: Remove invalid URL and add new reference
  samples/kretprobes: Fix return value if register_kretprobe() failed
  lib/bootconfig: Fix the xbc_get_info kerneldoc
  ...

2 files changed, 5 insertions, 16 deletions

diff --git a/arch/ia64/kernel/ftrace.c b/arch/ia64/kernel/ftrace.c
index b2ab2d58fb30..d6360fd404ab 100644
--- a/arch/ia64/kernel/ftrace.c
+++ b/arch/ia64/kernel/ftrace.c
@@ -194,9 +194,3 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 	flush_icache_range(addr, addr + 16);
 	return 0;
 }
-
-/* run from kstop_machine */
-int __init ftrace_dyn_arch_init(void)
-{
-	return 0;
-}
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 441ed04b1037..1a7bab1c5d7c 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -392,13 +392,13 @@ static void __kprobes set_current_kprobe(struct kprobe *p,
 	__this_cpu_write(current_kprobe, p);
 }
 
-static void kretprobe_trampoline(void)
+void __kretprobe_trampoline(void)
 {
 }
 
 int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
 {
-	regs->cr_iip = __kretprobe_trampoline_handler(regs, kretprobe_trampoline, NULL);
+	regs->cr_iip = __kretprobe_trampoline_handler(regs, NULL);
 	/*
 	 * By returning a non-zero value, we are telling
 	 * kprobe_handler() that we don't want the post_handler
@@ -414,7 +414,7 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
 	ri->fp = NULL;
 
 	/* Replace the return addr with trampoline addr */
-	regs->b0 = ((struct fnptr *)kretprobe_trampoline)->ip;
+	regs->b0 = (unsigned long)dereference_function_descriptor(__kretprobe_trampoline);
 }
 
 /* Check the instruction in the slot is break */
@@ -890,11 +890,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
 	return ret;
 }
 
-unsigned long arch_deref_entry_point(void *entry)
-{
-	return ((struct fnptr *)entry)->ip;
-}
-
 static struct kprobe trampoline_p = {
 	.pre_handler = trampoline_probe_handler
 };
@@ -902,14 +897,14 @@ static struct kprobe trampoline_p = {
 int __init arch_init_kprobes(void)
 {
 	trampoline_p.addr =
-		(kprobe_opcode_t *)((struct fnptr *)kretprobe_trampoline)->ip;
+		dereference_function_descriptor(__kretprobe_trampoline);
 	return register_kprobe(&trampoline_p);
 }
 
 int __kprobes arch_trampoline_kprobe(struct kprobe *p)
 {
 	if (p->addr ==
-		(kprobe_opcode_t *)((struct fnptr *)kretprobe_trampoline)->ip)
+		dereference_function_descriptor(__kretprobe_trampoline))
 		return 1;
 
 	return 0;