From 863981e96738983919de841ec669e157e6bdaeb0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Sun, 11 Sep 2016 04:34:46 -0300 Subject: Linux-libre 4.7.1-gnu --- drivers/hv/channel_mgmt.c | 58 +++++++++++++++++++++++++++++++++++------------ 1 file changed, 43 insertions(+), 15 deletions(-) (limited to 'drivers/hv/channel_mgmt.c') diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 38b682bab..b6c1211b4 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -597,27 +597,55 @@ static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) static void vmbus_wait_for_unload(void) { - int cpu = smp_processor_id(); - void *page_addr = hv_context.synic_message_page[cpu]; - struct hv_message *msg = (struct hv_message *)page_addr + - VMBUS_MESSAGE_SINT; + int cpu; + void *page_addr; + struct hv_message *msg; struct vmbus_channel_message_header *hdr; - bool unloaded = false; + u32 message_type; + /* + * CHANNELMSG_UNLOAD_RESPONSE is always delivered to the CPU which was + * used for initial contact or to CPU0 depending on host version. When + * we're crashing on a different CPU let's hope that IRQ handler on + * the cpu which receives CHANNELMSG_UNLOAD_RESPONSE is still + * functional and vmbus_unload_response() will complete + * vmbus_connection.unload_event. If not, the last thing we can do is + * read message pages for all CPUs directly. + */ while (1) { - if (READ_ONCE(msg->header.message_type) == HVMSG_NONE) { - mdelay(10); - continue; - } + if (completion_done(&vmbus_connection.unload_event)) + break; - hdr = (struct vmbus_channel_message_header *)msg->u.payload; - if (hdr->msgtype == CHANNELMSG_UNLOAD_RESPONSE) - unloaded = true; + for_each_online_cpu(cpu) { + page_addr = hv_context.synic_message_page[cpu]; + msg = (struct hv_message *)page_addr + + VMBUS_MESSAGE_SINT; - vmbus_signal_eom(msg); + message_type = READ_ONCE(msg->header.message_type); + if (message_type == HVMSG_NONE) + continue; - if (unloaded) - break; + hdr = (struct vmbus_channel_message_header *) + msg->u.payload; + + if (hdr->msgtype == CHANNELMSG_UNLOAD_RESPONSE) + complete(&vmbus_connection.unload_event); + + vmbus_signal_eom(msg, message_type); + } + + mdelay(10); + } + + /* + * We're crashing and already got the UNLOAD_RESPONSE, cleanup all + * maybe-pending messages on all CPUs to be able to receive new + * messages after we reconnect. + */ + for_each_online_cpu(cpu) { + page_addr = hv_context.synic_message_page[cpu]; + msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT; + msg->header.message_type = HVMSG_NONE; } } -- cgit v1.2.3-54-g00ecf