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-rw-r--r--arch/x86/kernel/cpu/common.c8
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce.c37
-rw-r--r--arch/x86/kernel/cpu/mtrr/cleanup.c2
-rw-r--r--arch/x86/kernel/entry_32.S13
-rw-r--r--arch/x86/kernel/entry_64.S44
-rw-r--r--arch/x86/kernel/ftrace.c102
-rw-r--r--arch/x86/kernel/hpet.c2
-rw-r--r--arch/x86/kernel/nmi.c6
-rw-r--r--arch/x86/kernel/ptrace.c6
-rw-r--r--arch/x86/kernel/signal.c62
-rw-r--r--arch/x86/kernel/traps.c8
11 files changed, 197 insertions, 93 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 82f29e7..6b9333b 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1101,14 +1101,20 @@ int is_debug_stack(unsigned long addr)
addr > (__get_cpu_var(debug_stack_addr) - DEBUG_STKSZ));
}
+static DEFINE_PER_CPU(u32, debug_stack_use_ctr);
+
void debug_stack_set_zero(void)
{
+ this_cpu_inc(debug_stack_use_ctr);
load_idt((const struct desc_ptr *)&nmi_idt_descr);
}
void debug_stack_reset(void)
{
- load_idt((const struct desc_ptr *)&idt_descr);
+ if (WARN_ON(!this_cpu_read(debug_stack_use_ctr)))
+ return;
+ if (this_cpu_dec_return(debug_stack_use_ctr) == 0)
+ load_idt((const struct desc_ptr *)&idt_descr);
}
#else /* CONFIG_X86_64 */
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index b772dd6..0a687fd 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1251,15 +1251,15 @@ void mce_log_therm_throt_event(__u64 status)
* poller finds an MCE, poll 2x faster. When the poller finds no more
* errors, poll 2x slower (up to check_interval seconds).
*/
-static int check_interval = 5 * 60; /* 5 minutes */
+static unsigned long check_interval = 5 * 60; /* 5 minutes */
-static DEFINE_PER_CPU(int, mce_next_interval); /* in jiffies */
+static DEFINE_PER_CPU(unsigned long, mce_next_interval); /* in jiffies */
static DEFINE_PER_CPU(struct timer_list, mce_timer);
-static void mce_start_timer(unsigned long data)
+static void mce_timer_fn(unsigned long data)
{
- struct timer_list *t = &per_cpu(mce_timer, data);
- int *n;
+ struct timer_list *t = &__get_cpu_var(mce_timer);
+ unsigned long iv;
WARN_ON(smp_processor_id() != data);
@@ -1272,13 +1272,14 @@ static void mce_start_timer(unsigned long data)
* Alert userspace if needed. If we logged an MCE, reduce the
* polling interval, otherwise increase the polling interval.
*/
- n = &__get_cpu_var(mce_next_interval);
+ iv = __this_cpu_read(mce_next_interval);
if (mce_notify_irq())
- *n = max(*n/2, HZ/100);
+ iv = max(iv, (unsigned long) HZ/100);
else
- *n = min(*n*2, (int)round_jiffies_relative(check_interval*HZ));
+ iv = min(iv * 2, round_jiffies_relative(check_interval * HZ));
+ __this_cpu_write(mce_next_interval, iv);
- t->expires = jiffies + *n;
+ t->expires = jiffies + iv;
add_timer_on(t, smp_processor_id());
}
@@ -1472,9 +1473,9 @@ static int __cpuinit __mcheck_cpu_apply_quirks(struct cpuinfo_x86 *c)
rdmsrl(msrs[i], val);
/* CntP bit set? */
- if (val & BIT(62)) {
- val &= ~BIT(62);
- wrmsrl(msrs[i], val);
+ if (val & BIT_64(62)) {
+ val &= ~BIT_64(62);
+ wrmsrl(msrs[i], val);
}
}
@@ -1556,17 +1557,17 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
static void __mcheck_cpu_init_timer(void)
{
struct timer_list *t = &__get_cpu_var(mce_timer);
- int *n = &__get_cpu_var(mce_next_interval);
+ unsigned long iv = __this_cpu_read(mce_next_interval);
- setup_timer(t, mce_start_timer, smp_processor_id());
+ setup_timer(t, mce_timer_fn, smp_processor_id());
if (mce_ignore_ce)
return;
- *n = check_interval * HZ;
- if (!*n)
+ __this_cpu_write(mce_next_interval, iv);
+ if (!iv)
return;
- t->expires = round_jiffies(jiffies + *n);
+ t->expires = round_jiffies(jiffies + iv);
add_timer_on(t, smp_processor_id());
}
@@ -2276,7 +2277,7 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
case CPU_DOWN_FAILED_FROZEN:
if (!mce_ignore_ce && check_interval) {
t->expires = round_jiffies(jiffies +
- __get_cpu_var(mce_next_interval));
+ per_cpu(mce_next_interval, cpu));
add_timer_on(t, cpu);
}
smp_call_function_single(cpu, mce_reenable_cpu, &action, 1);
diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c b/arch/x86/kernel/cpu/mtrr/cleanup.c
index ac140c7..bdda2e6 100644
--- a/arch/x86/kernel/cpu/mtrr/cleanup.c
+++ b/arch/x86/kernel/cpu/mtrr/cleanup.c
@@ -266,7 +266,7 @@ range_to_mtrr(unsigned int reg, unsigned long range_startk,
if (align > max_align)
align = max_align;
- sizek = 1 << align;
+ sizek = 1UL << align;
if (debug_print) {
char start_factor = 'K', size_factor = 'K';
unsigned long start_base, size_base;
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index 01ccf9b..623f288 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -316,7 +316,6 @@ ret_from_exception:
preempt_stop(CLBR_ANY)
ret_from_intr:
GET_THREAD_INFO(%ebp)
-resume_userspace_sig:
#ifdef CONFIG_VM86
movl PT_EFLAGS(%esp), %eax # mix EFLAGS and CS
movb PT_CS(%esp), %al
@@ -615,9 +614,13 @@ work_notifysig: # deal with pending signals and
# vm86-space
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
+ movb PT_CS(%esp), %bl
+ andb $SEGMENT_RPL_MASK, %bl
+ cmpb $USER_RPL, %bl
+ jb resume_kernel
xorl %edx, %edx
call do_notify_resume
- jmp resume_userspace_sig
+ jmp resume_userspace
ALIGN
work_notifysig_v86:
@@ -630,9 +633,13 @@ work_notifysig_v86:
#endif
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
+ movb PT_CS(%esp), %bl
+ andb $SEGMENT_RPL_MASK, %bl
+ cmpb $USER_RPL, %bl
+ jb resume_kernel
xorl %edx, %edx
call do_notify_resume
- jmp resume_userspace_sig
+ jmp resume_userspace
END(work_pending)
# perform syscall exit tracing
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 320852d..7d65133 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -191,6 +191,44 @@ ENDPROC(native_usergs_sysret64)
.endm
/*
+ * When dynamic function tracer is enabled it will add a breakpoint
+ * to all locations that it is about to modify, sync CPUs, update
+ * all the code, sync CPUs, then remove the breakpoints. In this time
+ * if lockdep is enabled, it might jump back into the debug handler
+ * outside the updating of the IST protection. (TRACE_IRQS_ON/OFF).
+ *
+ * We need to change the IDT table before calling TRACE_IRQS_ON/OFF to
+ * make sure the stack pointer does not get reset back to the top
+ * of the debug stack, and instead just reuses the current stack.
+ */
+#if defined(CONFIG_DYNAMIC_FTRACE) && defined(CONFIG_TRACE_IRQFLAGS)
+
+.macro TRACE_IRQS_OFF_DEBUG
+ call debug_stack_set_zero
+ TRACE_IRQS_OFF
+ call debug_stack_reset
+.endm
+
+.macro TRACE_IRQS_ON_DEBUG
+ call debug_stack_set_zero
+ TRACE_IRQS_ON
+ call debug_stack_reset
+.endm
+
+.macro TRACE_IRQS_IRETQ_DEBUG offset=ARGOFFSET
+ bt $9,EFLAGS-\offset(%rsp) /* interrupts off? */
+ jnc 1f
+ TRACE_IRQS_ON_DEBUG
+1:
+.endm
+
+#else
+# define TRACE_IRQS_OFF_DEBUG TRACE_IRQS_OFF
+# define TRACE_IRQS_ON_DEBUG TRACE_IRQS_ON
+# define TRACE_IRQS_IRETQ_DEBUG TRACE_IRQS_IRETQ
+#endif
+
+/*
* C code is not supposed to know about undefined top of stack. Every time
* a C function with an pt_regs argument is called from the SYSCALL based
* fast path FIXUP_TOP_OF_STACK is needed.
@@ -1098,7 +1136,7 @@ ENTRY(\sym)
subq $ORIG_RAX-R15, %rsp
CFI_ADJUST_CFA_OFFSET ORIG_RAX-R15
call save_paranoid
- TRACE_IRQS_OFF
+ TRACE_IRQS_OFF_DEBUG
movq %rsp,%rdi /* pt_regs pointer */
xorl %esi,%esi /* no error code */
subq $EXCEPTION_STKSZ, INIT_TSS_IST(\ist)
@@ -1393,7 +1431,7 @@ paranoidzeroentry machine_check *machine_check_vector(%rip)
ENTRY(paranoid_exit)
DEFAULT_FRAME
DISABLE_INTERRUPTS(CLBR_NONE)
- TRACE_IRQS_OFF
+ TRACE_IRQS_OFF_DEBUG
testl %ebx,%ebx /* swapgs needed? */
jnz paranoid_restore
testl $3,CS(%rsp)
@@ -1404,7 +1442,7 @@ paranoid_swapgs:
RESTORE_ALL 8
jmp irq_return
paranoid_restore:
- TRACE_IRQS_IRETQ 0
+ TRACE_IRQS_IRETQ_DEBUG 0
RESTORE_ALL 8
jmp irq_return
paranoid_userspace:
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 32ff365..c3a7cb4 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -100,7 +100,7 @@ static const unsigned char *ftrace_nop_replace(void)
}
static int
-ftrace_modify_code(unsigned long ip, unsigned const char *old_code,
+ftrace_modify_code_direct(unsigned long ip, unsigned const char *old_code,
unsigned const char *new_code)
{
unsigned char replaced[MCOUNT_INSN_SIZE];
@@ -141,7 +141,20 @@ int ftrace_make_nop(struct module *mod,
old = ftrace_call_replace(ip, addr);
new = ftrace_nop_replace();
- return ftrace_modify_code(rec->ip, old, new);
+ /*
+ * On boot up, and when modules are loaded, the MCOUNT_ADDR
+ * is converted to a nop, and will never become MCOUNT_ADDR
+ * again. This code is either running before SMP (on boot up)
+ * or before the code will ever be executed (module load).
+ * We do not want to use the breakpoint version in this case,
+ * just modify the code directly.
+ */
+ if (addr == MCOUNT_ADDR)
+ return ftrace_modify_code_direct(rec->ip, old, new);
+
+ /* Normal cases use add_brk_on_nop */
+ WARN_ONCE(1, "invalid use of ftrace_make_nop");
+ return -EINVAL;
}
int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
@@ -152,9 +165,47 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
old = ftrace_nop_replace();
new = ftrace_call_replace(ip, addr);
- return ftrace_modify_code(rec->ip, old, new);
+ /* Should only be called when module is loaded */
+ return ftrace_modify_code_direct(rec->ip, old, new);
}
+/*
+ * The modifying_ftrace_code is used to tell the breakpoint
+ * handler to call ftrace_int3_handler(). If it fails to
+ * call this handler for a breakpoint added by ftrace, then
+ * the kernel may crash.
+ *
+ * As atomic_writes on x86 do not need a barrier, we do not
+ * need to add smp_mb()s for this to work. It is also considered
+ * that we can not read the modifying_ftrace_code before
+ * executing the breakpoint. That would be quite remarkable if
+ * it could do that. Here's the flow that is required:
+ *
+ * CPU-0 CPU-1
+ *
+ * atomic_inc(mfc);
+ * write int3s
+ * <trap-int3> // implicit (r)mb
+ * if (atomic_read(mfc))
+ * call ftrace_int3_handler()
+ *
+ * Then when we are finished:
+ *
+ * atomic_dec(mfc);
+ *
+ * If we hit a breakpoint that was not set by ftrace, it does not
+ * matter if ftrace_int3_handler() is called or not. It will
+ * simply be ignored. But it is crucial that a ftrace nop/caller
+ * breakpoint is handled. No other user should ever place a
+ * breakpoint on an ftrace nop/caller location. It must only
+ * be done by this code.
+ */
+atomic_t modifying_ftrace_code __read_mostly;
+
+static int
+ftrace_modify_code(unsigned long ip, unsigned const char *old_code,
+ unsigned const char *new_code);
+
int ftrace_update_ftrace_func(ftrace_func_t func)
{
unsigned long ip = (unsigned long)(&ftrace_call);
@@ -163,13 +214,17 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
memcpy(old, &ftrace_call, MCOUNT_INSN_SIZE);
new = ftrace_call_replace(ip, (unsigned long)func);
+
+ /* See comment above by declaration of modifying_ftrace_code */
+ atomic_inc(&modifying_ftrace_code);
+
ret = ftrace_modify_code(ip, old, new);
+ atomic_dec(&modifying_ftrace_code);
+
return ret;
}
-int modifying_ftrace_code __read_mostly;
-
/*
* A breakpoint was added to the code address we are about to
* modify, and this is the handle that will just skip over it.
@@ -489,13 +544,46 @@ void ftrace_replace_code(int enable)
}
}
+static int
+ftrace_modify_code(unsigned long ip, unsigned const char *old_code,
+ unsigned const char *new_code)
+{
+ int ret;
+
+ ret = add_break(ip, old_code);
+ if (ret)
+ goto out;
+
+ run_sync();
+
+ ret = add_update_code(ip, new_code);
+ if (ret)
+ goto fail_update;
+
+ run_sync();
+
+ ret = ftrace_write(ip, new_code, 1);
+ if (ret) {
+ ret = -EPERM;
+ goto out;
+ }
+ run_sync();
+ out:
+ return ret;
+
+ fail_update:
+ probe_kernel_write((void *)ip, &old_code[0], 1);
+ goto out;
+}
+
void arch_ftrace_update_code(int command)
{
- modifying_ftrace_code++;
+ /* See comment above by declaration of modifying_ftrace_code */
+ atomic_inc(&modifying_ftrace_code);
ftrace_modify_all_code(command);
- modifying_ftrace_code--;
+ atomic_dec(&modifying_ftrace_code);
}
int __init ftrace_dyn_arch_init(void *data)
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index 9cc7b43..1460a5d 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -870,7 +870,7 @@ int __init hpet_enable(void)
else
pr_warn("HPET initial state will not be saved\n");
cfg &= ~(HPET_CFG_ENABLE | HPET_CFG_LEGACY);
- hpet_writel(cfg, HPET_Tn_CFG(i));
+ hpet_writel(cfg, HPET_CFG);
if (cfg)
pr_warn("HPET: Unrecognized bits %#x set in global cfg\n",
cfg);
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index 9087527..a0b2f84 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -444,14 +444,16 @@ static inline void nmi_nesting_preprocess(struct pt_regs *regs)
*/
if (unlikely(is_debug_stack(regs->sp))) {
debug_stack_set_zero();
- __get_cpu_var(update_debug_stack) = 1;
+ this_cpu_write(update_debug_stack, 1);
}
}
static inline void nmi_nesting_postprocess(void)
{
- if (unlikely(__get_cpu_var(update_debug_stack)))
+ if (unlikely(this_cpu_read(update_debug_stack))) {
debug_stack_reset();
+ this_cpu_write(update_debug_stack, 0);
+ }
}
#endif
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 13b1990..c4c6a5c 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -1211,12 +1211,6 @@ static long x32_arch_ptrace(struct task_struct *child,
0, sizeof(struct user_i387_struct),
datap);
- /* normal 64bit interface to access TLS data.
- Works just like arch_prctl, except that the arguments
- are reversed. */
- case PTRACE_ARCH_PRCTL:
- return do_arch_prctl(child, data, addr);
-
default:
return compat_ptrace_request(child, request, addr, data);
}
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 965dfda..21af737 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -555,7 +555,6 @@ unsigned long sys_sigreturn(struct pt_regs *regs)
sizeof(frame->extramask))))
goto badframe;
- sigdelsetmask(&set, ~_BLOCKABLE);
set_current_blocked(&set);
if (restore_sigcontext(regs, &frame->sc, &ax))
@@ -581,7 +580,6 @@ long sys_rt_sigreturn(struct pt_regs *regs)
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
goto badframe;
- sigdelsetmask(&set, ~_BLOCKABLE);
set_current_blocked(&set);
if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
@@ -647,42 +645,28 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
struct pt_regs *regs)
{
int usig = signr_convert(sig);
- sigset_t *set = &current->blocked;
- int ret;
-
- if (current_thread_info()->status & TS_RESTORE_SIGMASK)
- set = &current->saved_sigmask;
+ sigset_t *set = sigmask_to_save();
/* Set up the stack frame */
if (is_ia32) {
if (ka->sa.sa_flags & SA_SIGINFO)
- ret = ia32_setup_rt_frame(usig, ka, info, set, regs);
+ return ia32_setup_rt_frame(usig, ka, info, set, regs);
else
- ret = ia32_setup_frame(usig, ka, set, regs);
+ return ia32_setup_frame(usig, ka, set, regs);
#ifdef CONFIG_X86_X32_ABI
} else if (is_x32) {
- ret = x32_setup_rt_frame(usig, ka, info,
+ return x32_setup_rt_frame(usig, ka, info,
(compat_sigset_t *)set, regs);
#endif
} else {
- ret = __setup_rt_frame(sig, ka, info, set, regs);
- }
-
- if (ret) {
- force_sigsegv(sig, current);
- return -EFAULT;
+ return __setup_rt_frame(sig, ka, info, set, regs);
}
-
- current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
- return ret;
}
-static int
+static void
handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
struct pt_regs *regs)
{
- int ret;
-
/* Are we from a system call? */
if (syscall_get_nr(current, regs) >= 0) {
/* If so, check system call restarting.. */
@@ -713,10 +697,10 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
likely(test_and_clear_thread_flag(TIF_FORCED_TF)))
regs->flags &= ~X86_EFLAGS_TF;
- ret = setup_rt_frame(sig, ka, info, regs);
-
- if (ret)
- return ret;
+ if (setup_rt_frame(sig, ka, info, regs) < 0) {
+ force_sigsegv(sig, current);
+ return;
+ }
/*
* Clear the direction flag as per the ABI for function entry.
@@ -731,12 +715,8 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
*/
regs->flags &= ~X86_EFLAGS_TF;
- block_sigmask(ka, sig);
-
- tracehook_signal_handler(sig, info, ka, regs,
- test_thread_flag(TIF_SINGLESTEP));
-
- return 0;
+ signal_delivered(sig, info, ka, regs,
+ test_thread_flag(TIF_SINGLESTEP));
}
#ifdef CONFIG_X86_32
@@ -757,16 +737,6 @@ static void do_signal(struct pt_regs *regs)
siginfo_t info;
int signr;
- /*
- * We want the common case to go fast, which is why we may in certain
- * cases get here from kernel mode. Just return without doing anything
- * if so.
- * X86_32: vm86 regs switched out by assembly code before reaching
- * here, so testing against kernel CS suffices.
- */
- if (!user_mode(regs))
- return;
-
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
if (signr > 0) {
/* Whee! Actually deliver the signal. */
@@ -796,10 +766,7 @@ static void do_signal(struct pt_regs *regs)
* If there's no signal to deliver, we just put the saved sigmask
* back.
*/
- if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
- current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
- set_current_blocked(&current->saved_sigmask);
- }
+ restore_saved_sigmask();
}
/*
@@ -827,8 +794,6 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
- if (current->replacement_session_keyring)
- key_replace_session_keyring();
}
if (thread_info_flags & _TIF_USER_RETURN_NOTIFY)
fire_user_return_notifiers();
@@ -936,7 +901,6 @@ asmlinkage long sys32_x32_rt_sigreturn(struct pt_regs *regs)
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
goto badframe;
- sigdelsetmask(&set, ~_BLOCKABLE);
set_current_blocked(&set);
if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index ff08457..05b31d9 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -303,8 +303,12 @@ gp_in_kernel:
dotraplinkage void __kprobes notrace do_int3(struct pt_regs *regs, long error_code)
{
#ifdef CONFIG_DYNAMIC_FTRACE
- /* ftrace must be first, everything else may cause a recursive crash */
- if (unlikely(modifying_ftrace_code) && ftrace_int3_handler(regs))
+ /*
+ * ftrace must be first, everything else may cause a recursive crash.
+ * See note by declaration of modifying_ftrace_code in ftrace.c
+ */
+ if (unlikely(atomic_read(&modifying_ftrace_code)) &&
+ ftrace_int3_handler(regs))
return;
#endif
#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP