x86/kexec: crash_vmclear_local_vmcss needs __rcu

This removes the sparse warning:
arch/x86/kernel/crash.c:49:32: sparse: incompatible types in comparison expression (different address spaces)

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

2 files changed, 4 insertions, 3 deletions

diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
index 28feeba2fdd6..6080d2694bad 100644
--- a/arch/x86/include/asm/kexec.h
+++ b/arch/x86/include/asm/kexec.h
@@ -163,7 +163,8 @@ struct kimage_arch {
 };
 #endif
 
-extern void (*crash_vmclear_loaded_vmcss)(void);
+typedef void crash_vmclear_fn(void);
+extern crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss;
 
 #endif /* __ASSEMBLY__ */
 
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index 2f6b8e838d18..74467feb4dc5 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -38,12 +38,12 @@ int in_crash_kexec;
  *
  * protected by rcu.
  */
-void (*crash_vmclear_loaded_vmcss)(void) = NULL;
+crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss = NULL;
 EXPORT_SYMBOL_GPL(crash_vmclear_loaded_vmcss);
 
 static inline void cpu_crash_vmclear_loaded_vmcss(void)
 {
-        void (*do_vmclear_operation)(void) = NULL;
+        crash_vmclear_fn *do_vmclear_operation = NULL;
 
         rcu_read_lock();
         do_vmclear_operation = rcu_dereference(crash_vmclear_loaded_vmcss);