x86/smpboot: Init apic mapping before usage

[cascardo/linux.git] / kernel / panic.c

diff --git a/kernel/panic.c b/kernel/panic.c
index ca8cea1..e6480e2 100644 (file)
--- 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