diff options
Diffstat (limited to 'drivers/hv/channel_mgmt.c')
| -rw-r--r-- | drivers/hv/channel_mgmt.c | 55 |
1 files changed, 35 insertions, 20 deletions
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 43eaf54736f4..bd79d958f7d6 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -768,13 +768,19 @@ static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) free_cpumask_var(available_mask); } +#define UNLOAD_DELAY_UNIT_MS 10 /* 10 milliseconds */ +#define UNLOAD_WAIT_MS (100*1000) /* 100 seconds */ +#define UNLOAD_WAIT_LOOPS (UNLOAD_WAIT_MS/UNLOAD_DELAY_UNIT_MS) +#define UNLOAD_MSG_MS (5*1000) /* Every 5 seconds */ +#define UNLOAD_MSG_LOOPS (UNLOAD_MSG_MS/UNLOAD_DELAY_UNIT_MS) + static void vmbus_wait_for_unload(void) { int cpu; void *page_addr; struct hv_message *msg; struct vmbus_channel_message_header *hdr; - u32 message_type; + u32 message_type, i; /* * CHANNELMSG_UNLOAD_RESPONSE is always delivered to the CPU which was @@ -784,10 +790,18 @@ static void vmbus_wait_for_unload(void) * 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. + * + * Wait up to 100 seconds since an Azure host must writeback any dirty + * data in its disk cache before the VMbus UNLOAD request will + * complete. This flushing has been empirically observed to take up + * to 50 seconds in cases with a lot of dirty data, so allow additional + * leeway and for inaccuracies in mdelay(). But eventually time out so + * that the panic path can't get hung forever in case the response + * message isn't seen. */ - while (1) { + for (i = 1; i <= UNLOAD_WAIT_LOOPS; i++) { if (completion_done(&vmbus_connection.unload_event)) - break; + goto completed; for_each_online_cpu(cpu) { struct hv_per_cpu_context *hv_cpu @@ -810,9 +824,18 @@ static void vmbus_wait_for_unload(void) vmbus_signal_eom(msg, message_type); } - mdelay(10); + /* + * Give a notice periodically so someone watching the + * serial output won't think it is completely hung. + */ + if (!(i % UNLOAD_MSG_LOOPS)) + pr_notice("Waiting for VMBus UNLOAD to complete\n"); + + mdelay(UNLOAD_DELAY_UNIT_MS); } + pr_err("Continuing even though VMBus UNLOAD did not complete\n"); +completed: /* * We're crashing and already got the UNLOAD_RESPONSE, cleanup all * maybe-pending messages on all CPUs to be able to receive new @@ -986,8 +1009,7 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) vmbus_device_unregister(channel->device_obj); put_device(dev); } - } - if (channel->primary_channel != NULL) { + } else if (channel->primary_channel != NULL) { /* * Sub-channel is being rescinded. Following is the channel * close sequence when initiated from the driveri (refer to @@ -1228,6 +1250,8 @@ channel_message_table[CHANNELMSG_COUNT] = { { CHANNELMSG_19, 0, NULL }, { CHANNELMSG_20, 0, NULL }, { CHANNELMSG_TL_CONNECT_REQUEST, 0, NULL }, + { CHANNELMSG_22, 0, NULL }, + { CHANNELMSG_TL_CONNECT_RESULT, 0, NULL }, }; /* @@ -1239,23 +1263,14 @@ void vmbus_onmessage(void *context) { struct hv_message *msg = context; struct vmbus_channel_message_header *hdr; - int size; hdr = (struct vmbus_channel_message_header *)msg->u.payload; - size = msg->header.payload_size; - if (hdr->msgtype >= CHANNELMSG_COUNT) { - pr_err("Received invalid channel message type %d size %d\n", - hdr->msgtype, size); - print_hex_dump_bytes("", DUMP_PREFIX_NONE, - (unsigned char *)msg->u.payload, size); - return; - } - - if (channel_message_table[hdr->msgtype].message_handler) - channel_message_table[hdr->msgtype].message_handler(hdr); - else - pr_err("Unhandled channel message type %d\n", hdr->msgtype); + /* + * vmbus_on_msg_dpc() makes sure the hdr->msgtype here can not go + * out of bound and the message_handler pointer can not be NULL. + */ + channel_message_table[hdr->msgtype].message_handler(hdr); } /* |