1 files changed, 26 insertions, 7 deletions

diff --git a/arch/powerpc/kernel/crash.c b/arch/powerpc/kernel/crash.c
index d446755..b942980 100644
--- a/arch/powerpc/kernel/crash.c
+++ b/arch/powerpc/kernel/crash.c
@@ -30,6 +30,20 @@
 #include <asm/system.h>
 #include <asm/setjmp.h>
 
+/*
+ * The primary CPU waits a while for all secondary CPUs to enter. This is to
+ * avoid sending an IPI if the secondary CPUs are entering
+ * crash_kexec_secondary on their own (eg via a system reset).
+ *
+ * The secondary timeout has to be longer than the primary. Both timeouts are
+ * in milliseconds.
+ */
+#define PRIMARY_TIMEOUT		500
+#define SECONDARY_TIMEOUT	1000
+
+#define IPI_TIMEOUT		10000
+#define REAL_MODE_TIMEOUT	10000
+
 /* This keeps a track of which one is the crashing cpu. */
 int crashing_cpu = -1;
 static cpumask_t cpus_in_crash = CPU_MASK_NONE;
@@ -99,11 +113,9 @@ again:
 	 * FIXME: Until we will have the way to stop other CPUs reliably,
 	 * the crash CPU will send an IPI and wait for other CPUs to
 	 * respond.
-	 * Delay of at least 10 seconds.
 	 */
-	msecs = 10000;
+	msecs = IPI_TIMEOUT;
 	while ((cpumask_weight(&cpus_in_crash) < ncpus) && (--msecs > 0)) {
-		cpu_relax();
 		mdelay(1);
 	}
 
@@ -163,11 +175,11 @@ again:
 void crash_kexec_secondary(struct pt_regs *regs)
 {
 	unsigned long flags;
-	int msecs = 500;
+	int msecs = SECONDARY_TIMEOUT;
 
 	local_irq_save(flags);
 
-	/* Wait 500ms for the primary crash CPU to signal its progress */
+	/* Wait for the primary crash CPU to signal its progress */
 	while (crashing_cpu < 0) {
 		if (--msecs < 0) {
 			/* No response, kdump image may not have been loaded */
@@ -176,7 +188,6 @@ void crash_kexec_secondary(struct pt_regs *regs)
 		}
 
 		mdelay(1);
-		cpu_relax();
 	}
 
 	crash_ipi_callback(regs);
@@ -211,7 +222,7 @@ static void crash_kexec_wait_realmode(int cpu)
 	unsigned int msecs;
 	int i;
 
-	msecs = 10000;
+	msecs = REAL_MODE_TIMEOUT;
 	for (i=0; i < nr_cpu_ids && msecs > 0; i++) {
 		if (i == cpu)
 			continue;
@@ -306,6 +317,14 @@ void default_machine_crash_shutdown(struct pt_regs *regs)
 	 */
 	crashing_cpu = smp_processor_id();
 	crash_save_cpu(regs, crashing_cpu);
+
+	/*
+	 * If we came in via system reset, wait a while for the secondary
+	 * CPUs to enter.
+	 */
+	if (TRAP(regs) == 0x100)
+		mdelay(PRIMARY_TIMEOUT);
+
 	crash_kexec_prepare_cpus(crashing_cpu);
 	cpumask_set_cpu(crashing_cpu, &cpus_in_crash);
 	crash_kexec_wait_realmode(crashing_cpu);