From c5a9a020cfbc44833020007d6a77cd4200d7ced6 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 25 Jun 2005 14:57:58 -0700
Subject: [PATCH] --- yaml --- r: 3327 b: refs/heads/master c:
 c4ac4263a019c791e906f284bb03891d3c25a845 h: refs/heads/master i:   3325:
 aad439061ad9ce556b8f4f39f15c936dcf485654   3323:
 97aa55fd46cd1e7c84039c2ce181fceb016e9307   3319:
 33dd10dd84f18c50e4917ade80afa0ae0c45b8ab   3311:
 0c14f8f322e670f64b49502d7d2045b68aee21d1   3295:
 ff2490506aa8058cc67c5bf2bd372e0b38c863c2   3263:
 96bd72e219eb08a3faf7e4dcd53ed972dab317d7   3199:
 243006f54d2e9f1759ef8018dfe557300d40ee89   3071:
 13184a57c9e4b0f41e5900a2f4e883f32b00e412 v: v3

---
 [refs]                         |  2 +-
 trunk/arch/i386/kernel/crash.c | 56 ++++++++++++++++++++++++++++++++++
 2 files changed, 57 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index b2e9a3365f40..a9d78122e0e9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 5033cba087f6ac773002123aafbea1aad4267682
+refs/heads/master: c4ac4263a019c791e906f284bb03891d3c25a845
diff --git a/trunk/arch/i386/kernel/crash.c b/trunk/arch/i386/kernel/crash.c
index fa27a6c2abb6..882779c07874 100644
--- a/trunk/arch/i386/kernel/crash.c
+++ b/trunk/arch/i386/kernel/crash.c
@@ -23,12 +23,65 @@
 #include <asm/hardirq.h>
 #include <asm/nmi.h>
 #include <asm/hw_irq.h>
+#include <mach_ipi.h>
 
 #define MAX_NOTE_BYTES 1024
 typedef u32 note_buf_t[MAX_NOTE_BYTES/4];
 
 note_buf_t crash_notes[NR_CPUS];
 
+#ifdef CONFIG_SMP
+static atomic_t waiting_for_crash_ipi;
+
+static int crash_nmi_callback(struct pt_regs *regs, int cpu)
+{
+	local_irq_disable();
+	atomic_dec(&waiting_for_crash_ipi);
+	/* Assume hlt works */
+	__asm__("hlt");
+	for(;;);
+	return 1;
+}
+
+/*
+ * By using the NMI code instead of a vector we just sneak thru the
+ * word generator coming out with just what we want.  AND it does
+ * not matter if clustered_apic_mode is set or not.
+ */
+static void smp_send_nmi_allbutself(void)
+{
+	send_IPI_allbutself(APIC_DM_NMI);
+}
+
+static void nmi_shootdown_cpus(void)
+{
+	unsigned long msecs;
+	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
+
+	/* Would it be better to replace the trap vector here? */
+	set_nmi_callback(crash_nmi_callback);
+	/* Ensure the new callback function is set before sending
+	 * out the NMI
+	 */
+	wmb();
+
+	smp_send_nmi_allbutself();
+
+	msecs = 1000; /* Wait at most a second for the other cpus to stop */
+	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
+		mdelay(1);
+		msecs--;
+	}
+
+	/* Leave the nmi callback set */
+}
+#else
+static void nmi_shootdown_cpus(void)
+{
+	/* There are no cpus to shootdown */
+}
+#endif
+
 void machine_crash_shutdown(void)
 {
 	/* This function is only called after the system
@@ -39,4 +92,7 @@ void machine_crash_shutdown(void)
 	 * In practice this means shooting down the other cpus in
 	 * an SMP system.
 	 */
+	/* The kernel is broken so disable interrupts */
+	local_irq_disable();
+	nmi_shootdown_cpus();
 }