summaryrefslogtreecommitdiff
path: root/kernel/extable.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/extable.c')
-rw-r--r--kernel/extable.c45
1 files changed, 31 insertions, 14 deletions
diff --git a/kernel/extable.c b/kernel/extable.c
index 38c2412401a1..9aa1cc41ecf7 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -102,15 +102,7 @@ int core_kernel_data(unsigned long addr)
int __kernel_text_address(unsigned long addr)
{
- if (core_kernel_text(addr))
- return 1;
- if (is_module_text_address(addr))
- return 1;
- if (is_ftrace_trampoline(addr))
- return 1;
- if (is_kprobe_optinsn_slot(addr) || is_kprobe_insn_slot(addr))
- return 1;
- if (is_bpf_text_address(addr))
+ if (kernel_text_address(addr))
return 1;
/*
* There might be init symbols in saved stacktraces.
@@ -127,17 +119,42 @@ int __kernel_text_address(unsigned long addr)
int kernel_text_address(unsigned long addr)
{
+ bool no_rcu;
+ int ret = 1;
+
if (core_kernel_text(addr))
return 1;
+
+ /*
+ * If a stack dump happens while RCU is not watching, then
+ * RCU needs to be notified that it requires to start
+ * watching again. This can happen either by tracing that
+ * triggers a stack trace, or a WARN() that happens during
+ * coming back from idle, or cpu on or offlining.
+ *
+ * is_module_text_address() as well as the kprobe slots
+ * and is_bpf_text_address() require RCU to be watching.
+ */
+ no_rcu = !rcu_is_watching();
+
+ /* Treat this like an NMI as it can happen anywhere */
+ if (no_rcu)
+ rcu_nmi_enter();
+
if (is_module_text_address(addr))
- return 1;
+ goto out;
if (is_ftrace_trampoline(addr))
- return 1;
+ goto out;
if (is_kprobe_optinsn_slot(addr) || is_kprobe_insn_slot(addr))
- return 1;
+ goto out;
if (is_bpf_text_address(addr))
- return 1;
- return 0;
+ goto out;
+ ret = 0;
+out:
+ if (no_rcu)
+ rcu_nmi_exit();
+
+ return ret;
}
/*