summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorK. Y. Srinivasan <kys@microsoft.com>2016-12-07 01:16:28 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-03-12 06:41:49 +0100
commite44eab51e74c59a0b01c1fce2159c82b3c8a31b0 (patch)
treebe769d0de00d9f88b604a112386f4462c5f5b5a5
parent664f72a17f2c072175a0083388f315f811ff1acb (diff)
Drivers: hv: vmbus: Prevent sending data on a rescinded channel
commit e7e97dd8b77ee7366f2f8c70a033bf5fa05ec2e0 upstream. After the channel is rescinded, the host does not read from the rescinded channel. Fail writes to a channel that has already been rescinded. If we permit writes on a rescinded channel, since the host will not respond we will have situations where we will be unable to unload vmbus drivers that cannot have any outstanding requests to the host at the point they are unoaded. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/hv/ring_buffer.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 308dbda700eb..e94ed1c22c8b 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -298,6 +298,9 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
unsigned long flags = 0;
struct hv_ring_buffer_info *outring_info = &channel->outbound;
+ if (channel->rescind)
+ return -ENODEV;
+
for (i = 0; i < kv_count; i++)
totalbytes_towrite += kv_list[i].iov_len;
@@ -350,6 +353,10 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
spin_unlock_irqrestore(&outring_info->ring_lock, flags);
hv_signal_on_write(old_write, channel, kick_q);
+
+ if (channel->rescind)
+ return -ENODEV;
+
return 0;
}