[3.13-stable only] Revert "Drivers: hv: vmbus: Add support for VMBus panic notifier handler"

This reverts commit bb551e64.

New feature; not qualified for -stable kernels.
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

drivers/hv/hyperv_vmbus.h

@@ -49,17 +49,6 @@ enum hv_cpuid_function {
 	HVCPUID_IMPLEMENTATION_LIMITS		= 0x40000005,
 };
 
-#define  HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE   0x400
-
-#define HV_X64_MSR_CRASH_P0   0x40000100
-#define HV_X64_MSR_CRASH_P1   0x40000101
-#define HV_X64_MSR_CRASH_P2   0x40000102
-#define HV_X64_MSR_CRASH_P3   0x40000103
-#define HV_X64_MSR_CRASH_P4   0x40000104
-#define HV_X64_MSR_CRASH_CTL  0x40000105
-
-#define HV_CRASH_CTL_CRASH_NOTIFY 0x8000000000000000
-
 /* Define version of the synthetic interrupt controller. */
 #define HV_SYNIC_VERSION		(1)
 

drivers/hv/vmbus_drv.c

@@ -37,8 +37,6 @@
 #include <asm/hyperv.h>
 #include <asm/hypervisor.h>
 #include <asm/mshyperv.h>
-#include <linux/notifier.h>
-#include <linux/ptrace.h>
 #include "hyperv_vmbus.h"
 
 
@@ -48,36 +46,6 @@ static struct tasklet_struct msg_dpc;
 static struct completion probe_event;
 static int irq;
 
-int hyperv_panic_event(struct notifier_block *nb,
-			unsigned long event, void *ptr)
-{
-	struct pt_regs *regs;
-
-	regs = current_pt_regs();
-
-	wrmsrl(HV_X64_MSR_CRASH_P0, regs->ip);
-	wrmsrl(HV_X64_MSR_CRASH_P1, regs->ax);
-	wrmsrl(HV_X64_MSR_CRASH_P2, regs->bx);
-	wrmsrl(HV_X64_MSR_CRASH_P3, regs->cx);
-	wrmsrl(HV_X64_MSR_CRASH_P4, regs->dx);
-
-	/*
-	 * Let Hyper-V know there is crash data available
-	 */
-	wrmsrl(HV_X64_MSR_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY);
-	return NOTIFY_DONE;
-}
-
-static struct notifier_block hyperv_panic_block = {
-	.notifier_call = hyperv_panic_event,
-};
-
-struct resource hyperv_mmio = {
-	.name  = "hyperv mmio",
-	.flags = IORESOURCE_MEM,
-};
-EXPORT_SYMBOL_GPL(hyperv_mmio);
-
 static int vmbus_exists(void)
 {
 	if (hv_acpi_dev == NULL)
@@ -781,14 +749,6 @@ static int vmbus_bus_init(int irq)
 	if (ret)
 		goto err_alloc;
 
-	/*
-	 * Only register if the crash MSRs are available
-	 */
-	if (ms_hyperv.features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
-		atomic_notifier_chain_register(&panic_notifier_list,
-					       &hyperv_panic_block);
-	}
-
 	vmbus_request_offers();
 
 	return 0;