diff options
| author | K. Y. Srinivasan <kys@microsoft.com> | 2017-11-14 06:53:33 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-14 09:52:49 +0100 |
| commit | 3f77a2c68ba8377f7f7ddcadff5ffda238cb83db (patch) | |
| tree | ccc3dcf65975d45baf35d64f00da909678021cf0 /drivers/hv | |
| parent | 6c802ac42f970976d26241068e7202a84c9fd8b7 (diff) | |
Drivers: hv: vmbus: Fix a rescind issue
commit 7fa32e5ec28b1609abc0b797b58267f725fc3964 upstream.
The current rescind processing code will not correctly handle
the case where the host immediately rescinds a channel that has
been offerred. In this case, we could be blocked in the open call and
since the channel is rescinded, the host will not respond and we could
be blocked forever in the vmbus open call.i Fix this problem.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hv')
| -rw-r--r-- | drivers/hv/channel.c | 10 | ||||
| -rw-r--r-- | drivers/hv/channel_mgmt.c | 7 |
2 files changed, 12 insertions, 5 deletions
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 894b67ac2cae..05964347008d 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -640,22 +640,28 @@ void vmbus_close(struct vmbus_channel *channel) */ return; } - mutex_lock(&vmbus_connection.channel_mutex); /* * Close all the sub-channels first and then close the * primary channel. */ list_for_each_safe(cur, tmp, &channel->sc_list) { cur_channel = list_entry(cur, struct vmbus_channel, sc_list); - vmbus_close_internal(cur_channel); if (cur_channel->rescind) { + wait_for_completion(&cur_channel->rescind_event); + mutex_lock(&vmbus_connection.channel_mutex); + vmbus_close_internal(cur_channel); hv_process_channel_removal( cur_channel->offermsg.child_relid); + } else { + mutex_lock(&vmbus_connection.channel_mutex); + vmbus_close_internal(cur_channel); } + mutex_unlock(&vmbus_connection.channel_mutex); } /* * Now close the primary. */ + mutex_lock(&vmbus_connection.channel_mutex); vmbus_close_internal(channel); mutex_unlock(&vmbus_connection.channel_mutex); } diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 379b0df123be..65c6d6bdce4c 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -333,6 +333,7 @@ static struct vmbus_channel *alloc_channel(void) return NULL; spin_lock_init(&channel->lock); + init_completion(&channel->rescind_event); INIT_LIST_HEAD(&channel->sc_list); INIT_LIST_HEAD(&channel->percpu_list); @@ -883,6 +884,7 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) /* * Now wait for offer handling to complete. */ + vmbus_rescind_cleanup(channel); while (READ_ONCE(channel->probe_done) == false) { /* * We wait here until any channel offer is currently @@ -898,7 +900,6 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) if (channel->device_obj) { if (channel->chn_rescind_callback) { channel->chn_rescind_callback(channel); - vmbus_rescind_cleanup(channel); return; } /* @@ -907,7 +908,6 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) */ dev = get_device(&channel->device_obj->device); if (dev) { - vmbus_rescind_cleanup(channel); vmbus_device_unregister(channel->device_obj); put_device(dev); } @@ -921,13 +921,14 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) * 2. Then close the primary channel. */ mutex_lock(&vmbus_connection.channel_mutex); - vmbus_rescind_cleanup(channel); if (channel->state == CHANNEL_OPEN_STATE) { /* * The channel is currently not open; * it is safe for us to cleanup the channel. */ hv_process_channel_removal(rescind->child_relid); + } else { + complete(&channel->rescind_event); } mutex_unlock(&vmbus_connection.channel_mutex); } |