diff options
Diffstat (limited to 'kernel/drivers/hv/channel_mgmt.c')
| -rw-r--r-- | kernel/drivers/hv/channel_mgmt.c | 61 |
1 files changed, 57 insertions, 4 deletions
diff --git a/kernel/drivers/hv/channel_mgmt.c b/kernel/drivers/hv/channel_mgmt.c index 652afd11a..37238dffd 100644 --- a/kernel/drivers/hv/channel_mgmt.c +++ b/kernel/drivers/hv/channel_mgmt.c @@ -28,6 +28,7 @@ #include <linux/list.h> #include <linux/module.h> #include <linux/completion.h> +#include <linux/delay.h> #include <linux/hyperv.h> #include "hyperv_vmbus.h" @@ -191,6 +192,8 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid) if (channel == NULL) return; + BUG_ON(!channel->rescind); + if (channel->target_cpu != get_cpu()) { put_cpu(); smp_call_function_single(channel->target_cpu, @@ -230,9 +233,7 @@ void vmbus_free_channels(void) list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list, listentry) { - /* if we don't set rescind to true, vmbus_close_internal() - * won't invoke hv_process_channel_removal(). - */ + /* hv_process_channel_removal() needs this */ channel->rescind = true; vmbus_device_unregister(channel->device_obj); @@ -459,6 +460,17 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui cpumask_of_node(primary->numa_node)); cur_cpu = -1; + + /* + * Normally Hyper-V host doesn't create more subchannels than there + * are VCPUs on the node but it is possible when not all present VCPUs + * on the node are initialized by guest. Clear the alloced_cpus_in_node + * to start over. + */ + if (cpumask_equal(&primary->alloced_cpus_in_node, + cpumask_of_node(primary->numa_node))) + cpumask_clear(&primary->alloced_cpus_in_node); + while (true) { cur_cpu = cpumask_next(cur_cpu, &available_mask); if (cur_cpu >= nr_cpu_ids) { @@ -488,6 +500,40 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui channel->target_vp = hv_context.vp_index[cur_cpu]; } +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; + struct vmbus_channel_message_header *hdr; + bool unloaded = false; + + while (1) { + if (msg->header.message_type == HVMSG_NONE) { + mdelay(10); + continue; + } + + hdr = (struct vmbus_channel_message_header *)msg->u.payload; + if (hdr->msgtype == CHANNELMSG_UNLOAD_RESPONSE) + unloaded = true; + + msg->header.message_type = HVMSG_NONE; + /* + * header.message_type needs to be written before we do + * wrmsrl() below. + */ + mb(); + + if (msg->header.message_flags.msg_pending) + wrmsrl(HV_X64_MSR_EOM, 0); + + if (unloaded) + break; + } +} + /* * vmbus_unload_response - Handler for the unload response. */ @@ -513,7 +559,14 @@ void vmbus_initiate_unload(void) hdr.msgtype = CHANNELMSG_UNLOAD; vmbus_post_msg(&hdr, sizeof(struct vmbus_channel_message_header)); - wait_for_completion(&vmbus_connection.unload_event); + /* + * vmbus_initiate_unload() is also called on crash and the crash can be + * happening in an interrupt context, where scheduling is impossible. + */ + if (!in_interrupt()) + wait_for_completion(&vmbus_connection.unload_event); + else + vmbus_wait_for_unload(); } /* |