Merge 4.14-rc4 into staging-next

We want the staging/iio fixes in here as well to handle merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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;
 }
 
 /*