linux-stable/drivers/hv
Vitaly Kuznetsov 09a196288e Drivers: hv: vmbus: teardown hv_vmbus_con workqueue and vmbus_connection pages on shutdown
We need to destroy hv_vmbus_con on module shutdown, otherwise the following
crash is sometimes observed:

[   76.569845] hv_vmbus: Hyper-V Host Build:9600-6.3-17-0.17039; Vmbus version:3.0
[   82.598859] BUG: unable to handle kernel paging request at ffffffffa0003480
[   82.599287] IP: [<ffffffffa0003480>] 0xffffffffa0003480
[   82.599287] PGD 1f34067 PUD 1f35063 PMD 3f72d067 PTE 0
[   82.599287] Oops: 0010 [#1] SMP
[   82.599287] Modules linked in: [last unloaded: hv_vmbus]
[   82.599287] CPU: 0 PID: 26 Comm: kworker/0:1 Not tainted 3.19.0-rc5_bug923184+ #488
[   82.599287] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v1.0 11/26/2012
[   82.599287] Workqueue: hv_vmbus_con 0xffffffffa0003480
[   82.599287] task: ffff88007b6ddfa0 ti: ffff88007f8f8000 task.ti: ffff88007f8f8000
[   82.599287] RIP: 0010:[<ffffffffa0003480>]  [<ffffffffa0003480>] 0xffffffffa0003480
[   82.599287] RSP: 0018:ffff88007f8fbe00  EFLAGS: 00010202
...

To avoid memory leaks we need to free monitor_pages and int_page for
vmbus_connection. Implement vmbus_disconnect() function by separating cleanup
path from vmbus_connect().

As we use hv_vmbus_con to release channels (see free_channel() in channel_mgmt.c)
we need to make sure the work was done before we remove the queue, do that with
drain_workqueue(). We also need to avoid handling messages  which can (potentially)
create new channels, so set vmbus_connection.conn_state = DISCONNECTED at the very
beginning of vmbus_exit() and check for that in vmbus_onmessage_work().

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-01 19:29:05 -08:00
..
channel.c Drivers: hv: rename sc_lock to the more generic lock 2015-01-25 09:18:00 -08:00
channel_mgmt.c Drivers: hv: vmbus: avoid double kfree for device_obj 2015-03-01 19:29:05 -08:00
connection.c Drivers: hv: vmbus: teardown hv_vmbus_con workqueue and vmbus_connection pages on shutdown 2015-03-01 19:29:05 -08:00
hv.c Drivers: hv: vmbus: Implement a clockevent device 2015-01-25 09:17:57 -08:00
hv_balloon.c Drivers: hv: hv_balloon: Don't post pressure status from interrupt context 2015-01-25 09:17:57 -08:00
hv_fcopy.c hv: hv_fcopy: drop the obsolete message on transfer failure 2015-01-25 09:17:58 -08:00
hv_kvp.c Drivers: hv: kvp,vss: Fast propagation of userspace communication failure 2014-11-26 19:00:32 -08:00
hv_snapshot.c Drivers: hv: kvp,vss: Fast propagation of userspace communication failure 2014-11-26 19:00:32 -08:00
hv_util.c Drivers: hv: util: Fix a bug in the KVP code 2014-07-09 14:34:35 -07:00
hyperv_vmbus.h Drivers: hv: vmbus: teardown hv_vmbus_con workqueue and vmbus_connection pages on shutdown 2015-03-01 19:29:05 -08:00
Kconfig x86: Make Linux guest support optional 2013-03-04 13:14:25 -08:00
Makefile Drivers: hv: Implement the file copy service 2014-02-18 10:53:48 -08:00
ring_buffer.c Drivers: hv: vmbus: Enable interrupt driven flow control 2014-09-23 23:31:22 -07:00
vmbus_drv.c Drivers: hv: vmbus: teardown hv_vmbus_con workqueue and vmbus_connection pages on shutdown 2015-03-01 19:29:05 -08:00