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-rw-r--r--arch/x86/kernel/entry_32.S3
-rw-r--r--arch/x86/kernel/entry_64.S4
-rw-r--r--arch/x86/kernel/kprobes.c43
-rw-r--r--kernel/Makefile2
-rw-r--r--kernel/kprobes.c3
-rw-r--r--kernel/trace/Kconfig5
-rw-r--r--kernel/trace/Makefile6
-rw-r--r--kernel/trace/trace_events.c4
8 files changed, 46 insertions, 24 deletions
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index 061ac17ee974..f438a44bf8f9 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -1148,7 +1148,6 @@ ENTRY(ftrace_regs_caller)
* ip location, and move flags into the return ip location.
*/
pushl 4(%esp) /* save return ip into ip slot */
- subl $MCOUNT_INSN_SIZE, (%esp) /* Adjust ip */
pushl $0 /* Load 0 into orig_ax */
pushl %gs
@@ -1169,6 +1168,7 @@ ENTRY(ftrace_regs_caller)
movl $__KERNEL_CS,13*4(%esp)
movl 12*4(%esp), %eax /* Load ip (1st parameter) */
+ subl $MCOUNT_INSN_SIZE, %eax /* Adjust ip */
movl 0x4(%ebp), %edx /* Load parent ip (2nd parameter) */
leal function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */
pushl %esp /* Save pt_regs as 4th parameter */
@@ -1180,7 +1180,6 @@ GLOBAL(ftrace_regs_call)
movl 14*4(%esp), %eax /* Move flags back into cs */
movl %eax, 13*4(%esp) /* Needed to keep addl from modifying flags */
movl 12*4(%esp), %eax /* Get return ip from regs->ip */
- addl $MCOUNT_INSN_SIZE, %eax
movl %eax, 14*4(%esp) /* Put return ip back for ret */
popl %ebx
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index ed767b747fe5..e9cc2b32bdf4 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -165,6 +165,10 @@ GLOBAL(ftrace_regs_call)
movq EFLAGS(%rsp), %rax
movq %rax, SS(%rsp)
+ /* Handlers can change the RIP */
+ movq RIP(%rsp), %rax
+ movq %rax, SS+8(%rsp)
+
/* restore the rest of pt_regs */
movq R15(%rsp), %r15
movq R14(%rsp), %r14
diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index 47ae1023a93c..b7c2a85d1926 100644
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -541,6 +541,8 @@ reenter_kprobe(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb
return 1;
}
+static void __kprobes skip_singlestep(struct kprobe *p, struct pt_regs *regs,
+ struct kprobe_ctlblk *kcb);
/*
* Interrupts are disabled on entry as trap3 is an interrupt gate and they
* remain disabled throughout this function.
@@ -599,6 +601,12 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
} else if (kprobe_running()) {
p = __this_cpu_read(current_kprobe);
if (p->break_handler && p->break_handler(p, regs)) {
+#ifdef KPROBES_CAN_USE_FTRACE
+ if (kprobe_ftrace(p)) {
+ skip_singlestep(p, regs, kcb);
+ return 1;
+ }
+#endif
setup_singlestep(p, regs, kcb, 0);
return 1;
}
@@ -1053,6 +1061,21 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
}
#ifdef KPROBES_CAN_USE_FTRACE
+static void __kprobes skip_singlestep(struct kprobe *p, struct pt_regs *regs,
+ struct kprobe_ctlblk *kcb)
+{
+ /*
+ * Emulate singlestep (and also recover regs->ip)
+ * as if there is a 5byte nop
+ */
+ regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;
+ if (unlikely(p->post_handler)) {
+ kcb->kprobe_status = KPROBE_HIT_SSDONE;
+ p->post_handler(p, regs, 0);
+ }
+ __this_cpu_write(current_kprobe, NULL);
+}
+
/* Ftrace callback handler for kprobes */
void __kprobes kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *ops, struct pt_regs *regs)
@@ -1072,21 +1095,17 @@ void __kprobes kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
if (kprobe_running()) {
kprobes_inc_nmissed_count(p);
} else {
- regs->ip += sizeof(kprobe_opcode_t);
+ /* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */
+ regs->ip = ip + sizeof(kprobe_opcode_t);
__this_cpu_write(current_kprobe, p);
kcb->kprobe_status = KPROBE_HIT_ACTIVE;
- if (p->pre_handler)
- p->pre_handler(p, regs);
-
- if (unlikely(p->post_handler)) {
- /* Emulate singlestep as if there is a 5byte nop */
- regs->ip = ip + MCOUNT_INSN_SIZE;
- kcb->kprobe_status = KPROBE_HIT_SSDONE;
- p->post_handler(p, regs, 0);
- }
- __this_cpu_write(current_kprobe, NULL);
- regs->ip = ip; /* Recover for next callback */
+ if (!p->pre_handler || !p->pre_handler(p, regs))
+ skip_singlestep(p, regs, kcb);
+ /*
+ * If pre_handler returns !0, it sets regs->ip and
+ * resets current kprobe.
+ */
}
end:
local_irq_restore(flags);
diff --git a/kernel/Makefile b/kernel/Makefile
index c0cc67ad764c..29d993be7dba 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -98,7 +98,7 @@ obj-$(CONFIG_COMPAT_BINFMT_ELF) += elfcore.o
obj-$(CONFIG_BINFMT_ELF_FDPIC) += elfcore.o
obj-$(CONFIG_FUNCTION_TRACER) += trace/
obj-$(CONFIG_TRACING) += trace/
-obj-$(CONFIG_X86_DS) += trace/
+obj-$(CONFIG_TRACE_CLOCK) += trace/
obj-$(CONFIG_RING_BUFFER) += trace/
obj-$(CONFIG_TRACEPOINTS) += trace/
obj-$(CONFIG_IRQ_WORK) += irq_work.o
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 35b4315d84f5..098f396aa409 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1418,9 +1418,6 @@ static __kprobes int check_kprobe_address_safe(struct kprobe *p,
/* Given address is not on the instruction boundary */
if ((unsigned long)p->addr != ftrace_addr)
return -EILSEQ;
- /* break_handler (jprobe) can not work with ftrace */
- if (p->break_handler)
- return -EINVAL;
p->flags |= KPROBE_FLAG_FTRACE;
#else /* !KPROBES_CAN_USE_FTRACE */
return -EINVAL;
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 9301a0e35e0c..4cea4f41c1d9 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -62,8 +62,12 @@ config HAVE_C_RECORDMCOUNT
config TRACER_MAX_TRACE
bool
+config TRACE_CLOCK
+ bool
+
config RING_BUFFER
bool
+ select TRACE_CLOCK
config FTRACE_NMI_ENTER
bool
@@ -114,6 +118,7 @@ config TRACING
select NOP_TRACER
select BINARY_PRINTF
select EVENT_TRACING
+ select TRACE_CLOCK
config GENERIC_TRACER
bool
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 837090808aac..d7e2068e4b71 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -19,11 +19,7 @@ endif
CFLAGS_trace_events_filter.o := -I$(src)
-#
-# Make the trace clocks available generally: it's infrastructure
-# relied on by ptrace for example:
-#
-obj-y += trace_clock.o
+obj-$(CONFIG_TRACE_CLOCK) += trace_clock.o
obj-$(CONFIG_FUNCTION_TRACER) += libftrace.o
obj-$(CONFIG_RING_BUFFER) += ring_buffer.o
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 6825d833a257..bbb0e63d78e9 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1646,9 +1646,11 @@ static __init void event_trace_self_tests(void)
event_test_stuff();
ret = __ftrace_set_clr_event(NULL, system->name, NULL, 0);
- if (WARN_ON_ONCE(ret))
+ if (WARN_ON_ONCE(ret)) {
pr_warning("error disabling system %s\n",
system->name);
+ continue;
+ }
pr_cont("OK\n");
}