diff options
| -rw-r--r-- | drivers/hv/connection.c | 20 | ||||
| -rw-r--r-- | drivers/hv/hv.c | 7 | ||||
| -rw-r--r-- | drivers/hv/hyperv_vmbus.h | 11 | ||||
| -rw-r--r-- | drivers/hv/vmbus_drv.c | 20 |
4 files changed, 31 insertions, 27 deletions
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 74e77de89b4f..f4bd306d2cef 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -69,7 +69,6 @@ MODULE_PARM_DESC(max_version, int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) { int ret = 0; - unsigned int cur_cpu; struct vmbus_channel_initiate_contact *msg; unsigned long flags; @@ -102,24 +101,7 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages[0]); msg->monitor_page2 = virt_to_phys(vmbus_connection.monitor_pages[1]); - /* - * We want all channel messages to be delivered on CPU 0. - * This has been the behavior pre-win8. This is not - * perf issue and having all channel messages delivered on CPU 0 - * would be ok. - * For post win8 hosts, we support receiving channel messagges on - * all the CPUs. This is needed for kexec to work correctly where - * the CPU attempting to connect may not be CPU 0. - */ - if (version >= VERSION_WIN8_1) { - cur_cpu = get_cpu(); - msg->target_vcpu = hv_cpu_number_to_vp_number(cur_cpu); - vmbus_connection.connect_cpu = cur_cpu; - put_cpu(); - } else { - msg->target_vcpu = 0; - vmbus_connection.connect_cpu = 0; - } + msg->target_vcpu = hv_cpu_number_to_vp_number(VMBUS_CONNECT_CPU); /* * Add to list before we send the request since we may diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index 6098e0cbdb4b..e2b331045464 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -250,6 +250,13 @@ int hv_synic_cleanup(unsigned int cpu) unsigned long flags; /* + * Hyper-V does not provide a way to change the connect CPU once + * it is set; we must prevent the connect CPU from going offline. + */ + if (cpu == VMBUS_CONNECT_CPU) + return -EBUSY; + + /* * Search for channels which are bound to the CPU we're about to * cleanup. In case we find one and vmbus is still connected we need to * fail, this will effectively prevent CPU offlining. There is no way diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index ab560ac9c040..000740d053a2 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -212,12 +212,13 @@ enum vmbus_connect_state { #define MAX_SIZE_CHANNEL_MESSAGE HV_MESSAGE_PAYLOAD_BYTE_COUNT -struct vmbus_connection { - /* - * CPU on which the initial host contact was made. - */ - int connect_cpu; +/* + * The CPU that Hyper-V will interrupt for VMBUS messages, such as + * CHANNELMSG_OFFERCHANNEL and CHANNELMSG_RESCIND_CHANNELOFFER. + */ +#define VMBUS_CONNECT_CPU 0 +struct vmbus_connection { u32 msg_conn_id; atomic_t offer_in_progress; diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 3a05e1bc359c..495337ec68f1 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1109,14 +1109,28 @@ void vmbus_on_msg_dpc(unsigned long data) /* * If we are handling the rescind message; * schedule the work on the global work queue. + * + * The OFFER message and the RESCIND message should + * not be handled by the same serialized work queue, + * because the OFFER handler may call vmbus_open(), + * which tries to open the channel by sending an + * OPEN_CHANNEL message to the host and waits for + * the host's response; however, if the host has + * rescinded the channel before it receives the + * OPEN_CHANNEL message, the host just silently + * ignores the OPEN_CHANNEL message; as a result, + * the guest's OFFER handler hangs for ever, if we + * handle the RESCIND message in the same serialized + * work queue: the RESCIND handler can not start to + * run before the OFFER handler finishes. */ - schedule_work_on(vmbus_connection.connect_cpu, + schedule_work_on(VMBUS_CONNECT_CPU, &ctx->work); break; case CHANNELMSG_OFFERCHANNEL: atomic_inc(&vmbus_connection.offer_in_progress); - queue_work_on(vmbus_connection.connect_cpu, + queue_work_on(VMBUS_CONNECT_CPU, vmbus_connection.work_queue, &ctx->work); break; @@ -1164,7 +1178,7 @@ static void vmbus_force_channel_rescinded(struct vmbus_channel *channel) INIT_WORK(&ctx->work, vmbus_onmessage_work); - queue_work_on(vmbus_connection.connect_cpu, + queue_work_on(VMBUS_CONNECT_CPU, vmbus_connection.work_queue, &ctx->work); } |