kernel.git/drivers/hv/channel.c, branch linux-4.4.y

Drivers: hv: get rid of timeout in vmbus_open()

2017-04-27T07:09:32Z

commit 396e287fa2ff46e83ae016cdcb300c3faa3b02f6 upstream. vmbus_teardown_gpadl() can result in infinite wait when it is called on 5 second timeout in vmbus_open(). The issue is caused by the fact that gpadl teardown operation won't ever succeed for an opened channel and the timeout isn't always enough. As a guest, we can always trust the host to respond to our request (and there is nothing we can do if it doesn't). Signed-off-by: Vitaly Kuznetsov Signed-off-by: K. Y. Srinivasan Signed-off-by: Sumit Semwal Signed-off-by: Greg Kroah-Hartman

Drivers: hv: don't leak memory in vmbus_establish_gpadl()

2017-04-27T07:09:32Z

commit 7cc80c98070ccc7940fc28811c92cca0a681015d upstream. In some cases create_gpadl_header() allocates submessages but we never free them. [sumits] Note for stable: Upstream commit 4d63763296ab7865a98bc29cc7d77145815ef89f: (Drivers: hv: get rid of redundant messagecount in create_gpadl_header()) changes the list usage to initialize list header in all cases; that patch isn't added to stable, so the current patch is modified a little bit from the upstream commit to check if the list is valid or not. Signed-off-by: Vitaly Kuznetsov Signed-off-by: K. Y. Srinivasan Signed-off-by: Sumit Semwal Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: fix rescind-offer handling for device without a driver

2016-09-15T06:27:41Z

[ Upstream commit 34c6801e3310ad286c7bb42bc88d42926b8f99bf ] In the path vmbus_onoffer_rescind() -> vmbus_device_unregister() -> device_unregister() -> ... -> __device_release_driver(), we can see for a device without a driver loaded: dev->driver is NULL, so dev->bus->remove(dev), namely vmbus_remove(), isn't invoked. As a result, vmbus_remove() -> hv_process_channel_removal() isn't invoked and some cleanups(like sending a CHANNELMSG_RELID_RELEASED message to the host) aren't done. We can demo the issue this way: 1. rmmod hv_utils; 2. disable the Heartbeat Integration Service in Hyper-V Manager and lsvmbus shows the device disappears. 3. re-enable the Heartbeat in Hyper-V Manager and modprobe hv_utils, but lsvmbus shows the device can't appear again. This is because, the host thinks the VM hasn't released the relid, so can't re-offer the device to the VM. We can fix the issue by moving hv_process_channel_removal() from vmbus_close_internal() to vmbus_device_release(), since the latter is always invoked on device_unregister(), whether or not the dev has a driver loaded. Signed-off-by: Dexuan Cui Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: serialize process_chn_event() and vmbus_close_internal()

2016-09-15T06:27:40Z

[ Upstream commit 63d55b2aeb5e4faa170316fee73c3c47ea9268c7 ] process_chn_event(), running in the tasklet, can race with vmbus_close_internal() in the case of SMP guest, e.g., when the former is accessing channel->inbound.ring_buffer, the latter could be freeing the ring_buffer pages. To resolve the race, we can serialize them by disabling the tasklet when the latter is running here. Signed-off-by: Dexuan Cui Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Fix a Host signaling bug

2016-03-03T23:07:16Z

commit 8599846d73997cdbccf63f23394d871cfad1e5e6 upstream. Currently we have two policies for deciding when to signal the host: One based on the ring buffer state and the other based on what the VMBUS client driver wants to do. Consider the case when the client wants to explicitly control when to signal the host. In this case, if the client were to defer signaling, we will not be able to signal the host subsequently when the client does want to signal since the ring buffer state will prevent the signaling. Implement logic to have only one signaling policy in force for a given channel. Signed-off-by: K. Y. Srinivasan Reviewed-by: Haiyang Zhang Tested-by: Haiyang Zhang Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Permit sending of packets without payload

2015-08-05T05:28:39Z

The guest may have to send a completion packet back to the host. To support this usage, permit sending a packet without a payload - we would be only sending the descriptor in this case. Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Allocate ring buffer memory in NUMA aware fashion

2015-06-12T23:58:33Z

Allocate ring buffer memory from the NUMA node assigned to the channel. Since this is a performance and not a correctness issue, if the node specific allocation were to fail, fall back and allocate without specifying the node. Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: do cleanup on all vmbus_open() failure paths

2015-05-24T19:19:00Z

In case there was an error reported in the response to the CHANNELMSG_OPENCHANNEL call we need to do the cleanup as a vmbus_open() user won't be doing it after receiving an error. The cleanup should be done on all failure paths. We also need to avoid returning open_info->response.open_result.status as the return value as all other errors we return from vmbus_open() are -EXXX and vmbus_open() callers are not supposed to analyze host error codes. Signed-off-by: Vitaly Kuznetsov Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Fix a siganlling host signalling issue

2015-03-25T10:53:55Z

Handle the case when the write to the ringbuffer fails. In this case, unconditionally signal the host. Since we may have deferred signalling the host based on the kick_q parameter, signalling the host unconditionally in this case deals with the issue. Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: Export the vmbus_sendpacket_pagebuffer_ctl()

2015-03-25T10:53:55Z

Export the vmbus_sendpacket_pagebuffer_ctl() interface. This export will be used by the netvsc driver. Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman