1 files changed, 40 insertions, 7 deletions

diff --git a/kernel/panic.c b/kernel/panic.c
index ca8cea1ef673..e6480e20379e 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -71,6 +71,32 @@ void __weak nmi_panic_self_stop(struct pt_regs *regs)
         panic_smp_self_stop();
 }
 
+/*
+ * Stop other CPUs in panic.  Architecture dependent code may override this
+ * with more suitable version.  For example, if the architecture supports
+ * crash dump, it should save registers of each stopped CPU and disable
+ * per-CPU features such as virtualization extensions.
+ */
+void __weak crash_smp_send_stop(void)
+{
+        static int cpus_stopped;
+
+        /*
+         * This function can be called twice in panic path, but obviously
+         * we execute this only once.
+         */
+        if (cpus_stopped)
+                return;
+
+        /*
+         * Note smp_send_stop is the usual smp shutdown function, which
+         * unfortunately means it may not be hardened to work in a panic
+         * situation.
+         */
+        smp_send_stop();
+        cpus_stopped = 1;
+}
+
 atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID);
 
 /*
@@ -164,14 +190,21 @@ void panic(const char *fmt, ...)
         if (!_crash_kexec_post_notifiers) {
                 printk_nmi_flush_on_panic();
                 __crash_kexec(NULL);
-        }
 
-        /*
-         * Note smp_send_stop is the usual smp shutdown function, which
-         * unfortunately means it may not be hardened to work in a panic
-         * situation.
-         */
-        smp_send_stop();
+                /*
+                 * Note smp_send_stop is the usual smp shutdown function, which
+                 * unfortunately means it may not be hardened to work in a
+                 * panic situation.
+                 */
+                smp_send_stop();
+        } else {
+                /*
+                 * If we want to do crash dump after notifier calls and
+                 * kmsg_dump, we will need architecture dependent extra
+                 * works in addition to stopping other CPUs.
+                 */
+                crash_smp_send_stop();
+        }
 
         /*
          * Run any panic handlers, including those that might need to