From ccb61f8a99e6c29df4fb96a65dad4fad740d5be9 Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Thu, 22 Dec 2016 16:54:00 -0800 Subject: Drivers: hv: vmbus: Fix a rescind handling bug The host can rescind a channel that has been offered to the guest and once the channel is rescinded, the host does not respond to any requests on that channel. Deal with the case where the guest may be blocked waiting for a response from the host. Signed-off-by: K. Y. Srinivasan Cc: Signed-off-by: Greg Kroah-Hartman --- drivers/hv/channel_mgmt.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'drivers/hv/channel_mgmt.c') diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index b1e85d24bb4e..0af7e39006c8 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -147,6 +147,29 @@ static const struct { { HV_RDV_GUID }, }; +/* + * The rescinded channel may be blocked waiting for a response from the host; + * take care of that. + */ +static void vmbus_rescind_cleanup(struct vmbus_channel *channel) +{ + struct vmbus_channel_msginfo *msginfo; + unsigned long flags; + + + spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); + + list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, + msglistentry) { + + if (msginfo->waiting_channel == channel) { + complete(&msginfo->waitevent); + break; + } + } + spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); +} + static bool is_unsupported_vmbus_devs(const uuid_le *guid) { int i; @@ -825,6 +848,8 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) channel->rescind = true; spin_unlock_irqrestore(&channel->lock, flags); + vmbus_rescind_cleanup(channel); + if (channel->device_obj) { if (channel->chn_rescind_callback) { channel->chn_rescind_callback(channel); -- cgit v1.2.3-58-ga151