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-rw-r--r--arch/x86/kernel/ftrace_64.S15
-rw-r--r--arch/x86/kernel/kprobes/ftrace.c15
2 files changed, 25 insertions, 5 deletions
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S
index ac3d5f22fe64..0d54099c2a3a 100644
--- a/arch/x86/kernel/ftrace_64.S
+++ b/arch/x86/kernel/ftrace_64.S
@@ -140,16 +140,27 @@ SYM_FUNC_START(ftrace_caller)
/* save_mcount_regs fills in first two parameters */
save_mcount_regs
+ /* Stack - skipping return address of ftrace_caller */
+ leaq MCOUNT_REG_SIZE+8(%rsp), %rcx
+ movq %rcx, RSP(%rsp)
+
SYM_INNER_LABEL(ftrace_caller_op_ptr, SYM_L_GLOBAL)
/* Load the ftrace_ops into the 3rd parameter */
movq function_trace_op(%rip), %rdx
- /* regs go into 4th parameter (but make it NULL) */
- movq $0, %rcx
+ /* regs go into 4th parameter */
+ leaq (%rsp), %rcx
+
+ /* Only ops with REGS flag set should have CS register set */
+ movq $0, CS(%rsp)
SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL)
call ftrace_stub
+ /* Handlers can change the RIP */
+ movq RIP(%rsp), %rax
+ movq %rax, MCOUNT_REG_SIZE(%rsp)
+
restore_mcount_regs
/*
diff --git a/arch/x86/kernel/kprobes/ftrace.c b/arch/x86/kernel/kprobes/ftrace.c
index 681a4b36e9bb..373e5fa3ce1f 100644
--- a/arch/x86/kernel/kprobes/ftrace.c
+++ b/arch/x86/kernel/kprobes/ftrace.c
@@ -14,15 +14,21 @@
/* Ftrace callback handler for kprobes -- called under preepmt disabed */
void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *ops, struct pt_regs *regs)
+ struct ftrace_ops *ops, struct ftrace_regs *fregs)
{
+ struct pt_regs *regs = ftrace_get_regs(fregs);
struct kprobe *p;
struct kprobe_ctlblk *kcb;
+ int bit;
- /* Preempt is disabled by ftrace */
+ bit = ftrace_test_recursion_trylock(ip, parent_ip);
+ if (bit < 0)
+ return;
+
+ preempt_disable_notrace();
p = get_kprobe((kprobe_opcode_t *)ip);
if (unlikely(!p) || kprobe_disabled(p))
- return;
+ goto out;
kcb = get_kprobe_ctlblk();
if (kprobe_running()) {
@@ -52,6 +58,9 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
*/
__this_cpu_write(current_kprobe, NULL);
}
+out:
+ preempt_enable_notrace();
+ ftrace_test_recursion_unlock(bit);
}
NOKPROBE_SYMBOL(kprobe_ftrace_handler);