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-rw-r--r--arch/x86/include/asm/paravirt.h10
-rw-r--r--kernel/module.c12
-rw-r--r--kernel/trace/trace.c19
3 files changed, 36 insertions, 5 deletions
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 18e3b8a8709..ef9975812c7 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -824,27 +824,27 @@ static __always_inline void arch_spin_unlock(struct arch_spinlock *lock)
#define __PV_IS_CALLEE_SAVE(func) \
((struct paravirt_callee_save) { func })
-static inline unsigned long arch_local_save_flags(void)
+static inline notrace unsigned long arch_local_save_flags(void)
{
return PVOP_CALLEE0(unsigned long, pv_irq_ops.save_fl);
}
-static inline void arch_local_irq_restore(unsigned long f)
+static inline notrace void arch_local_irq_restore(unsigned long f)
{
PVOP_VCALLEE1(pv_irq_ops.restore_fl, f);
}
-static inline void arch_local_irq_disable(void)
+static inline notrace void arch_local_irq_disable(void)
{
PVOP_VCALLEE0(pv_irq_ops.irq_disable);
}
-static inline void arch_local_irq_enable(void)
+static inline notrace void arch_local_irq_enable(void)
{
PVOP_VCALLEE0(pv_irq_ops.irq_enable);
}
-static inline unsigned long arch_local_irq_save(void)
+static inline notrace unsigned long arch_local_irq_save(void)
{
unsigned long f;
diff --git a/kernel/module.c b/kernel/module.c
index 437a74a7524..d190664f25f 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2326,6 +2326,18 @@ static void find_module_sections(struct module *mod, struct load_info *info)
kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
mod->num_trace_events, GFP_KERNEL);
#endif
+#ifdef CONFIG_TRACING
+ mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
+ sizeof(*mod->trace_bprintk_fmt_start),
+ &mod->num_trace_bprintk_fmt);
+ /*
+ * This section contains pointers to allocated objects in the trace
+ * code and not scanning it leads to false positives.
+ */
+ kmemleak_scan_area(mod->trace_bprintk_fmt_start,
+ sizeof(*mod->trace_bprintk_fmt_start) *
+ mod->num_trace_bprintk_fmt, GFP_KERNEL);
+#endif
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
/* sechdrs[0].sh_size is always zero */
mod->ftrace_callsites = section_objs(info, "__mcount_loc",
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 82d9b8106cd..ee6a7339cf0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1284,6 +1284,8 @@ void trace_dump_stack(void)
__ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count());
}
+static DEFINE_PER_CPU(int, user_stack_count);
+
void
ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
{
@@ -1302,6 +1304,18 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
if (unlikely(in_nmi()))
return;
+ /*
+ * prevent recursion, since the user stack tracing may
+ * trigger other kernel events.
+ */
+ preempt_disable();
+ if (__this_cpu_read(user_stack_count))
+ goto out;
+
+ __this_cpu_inc(user_stack_count);
+
+
+
event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK,
sizeof(*entry), flags, pc);
if (!event)
@@ -1319,6 +1333,11 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
save_stack_trace_user(&trace);
if (!filter_check_discard(call, entry, buffer, event))
ring_buffer_unlock_commit(buffer, event);
+
+ __this_cpu_dec(user_stack_count);
+
+ out:
+ preempt_enable();
}
#ifdef UNUSED