From 5ab05951c586a2ed9e19a3ed8c437346bfabbfb7 Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Sat, 1 Dec 2012 06:46:55 -0800 Subject: [PATCH] Drivers: hv: Add a check to deal with spurious interrupts We establish the handler before we have fully initialized the VMBUS state. Deal with spurious interrupts. Signed-off-by: K. Y. Srinivasan Reviewed-by: Haiyang Zhang Signed-off-by: Greg Kroah-Hartman --- drivers/hv/vmbus_drv.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index e066d418be97..797142c07fa0 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -454,6 +454,12 @@ static irqreturn_t vmbus_isr(int irq, void *dev_id) union hv_synic_event_flags *event; bool handled = false; + page_addr = hv_context.synic_event_page[cpu]; + if (page_addr == NULL) + return IRQ_NONE; + + event = (union hv_synic_event_flags *)page_addr + + VMBUS_MESSAGE_SINT; /* * Check for events before checking for messages. This is the order * in which events and messages are checked in Windows guests on @@ -463,10 +469,6 @@ static irqreturn_t vmbus_isr(int irq, void *dev_id) if ((vmbus_proto_version == VERSION_WS2008) || (vmbus_proto_version == VERSION_WIN7)) { - page_addr = hv_context.synic_event_page[cpu]; - event = (union hv_synic_event_flags *)page_addr + - VMBUS_MESSAGE_SINT; - /* Since we are a child, we only need to check bit 0 */ if (sync_test_and_clear_bit(0, (unsigned long *) &event->flags32[0])) {