1 files changed, 31 insertions, 0 deletions

diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index 3dca15634e69..44d6f7545505 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -17,6 +17,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/cpu.h>
 #include <linux/cpu_pm.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
@@ -296,6 +297,35 @@ static void fpsimd_pm_init(void)
 static inline void fpsimd_pm_init(void) { }
 #endif /* CONFIG_CPU_PM */
 
+#ifdef CONFIG_HOTPLUG_CPU
+static int fpsimd_cpu_hotplug_notifier(struct notifier_block *nfb,
+                                       unsigned long action,
+                                       void *hcpu)
+{
+        unsigned int cpu = (long)hcpu;
+
+        switch (action) {
+        case CPU_DEAD:
+        case CPU_DEAD_FROZEN:
+                per_cpu(fpsimd_last_state, cpu) = NULL;
+                break;
+        }
+        return NOTIFY_OK;
+}
+
+static struct notifier_block fpsimd_cpu_hotplug_notifier_block = {
+        .notifier_call = fpsimd_cpu_hotplug_notifier,
+};
+
+static inline void fpsimd_hotplug_init(void)
+{
+        register_cpu_notifier(&fpsimd_cpu_hotplug_notifier_block);
+}
+
+#else
+static inline void fpsimd_hotplug_init(void) { }
+#endif
+
 /*
  * FP/SIMD support code initialisation.
  */
@@ -315,6 +345,7 @@ static int __init fpsimd_init(void)
                 elf_hwcap |= HWCAP_ASIMD;
 
         fpsimd_pm_init();
+        fpsimd_hotplug_init();
 
         return 0;
 }