linux/drivers/hv
Michael Kelley 655296c8bb Drivers: hv: vmbus: Fix ring buffer signaling
Fix bugs in signaling the Hyper-V host when freeing space in the
host->guest ring buffer:

1. The interrupt_mask must not be used to determine whether to signal
   on the host->guest ring buffer
2. The ring buffer write_index must be read (via hv_get_bytes_to_write)
   *after* pending_send_sz is read in order to avoid a race condition
3. Comparisons with pending_send_sz must treat the "equals" case as
   not-enough-space
4. Don't signal if the pending_send_sz feature is not present. Older
   versions of Hyper-V that don't implement this feature will poll.

Fixes: 03bad714a1 ("vmbus: more host signalling avoidance")

Cc: Stable <stable@vger.kernel.org> # 4.14 and above
Signed-off-by: Michael Kelley <mhkelley@outlook.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-06 09:52:59 -08:00
..
channel_mgmt.c
channel.c
connection.c
hv_balloon.c
hv_fcopy.c
hv_kvp.c
hv_snapshot.c
hv_trace.c
hv_trace.h
hv_util.c
hv_utils_transport.c
hv_utils_transport.h
hv.c
hyperv_vmbus.h
Kconfig
Makefile
ring_buffer.c Drivers: hv: vmbus: Fix ring buffer signaling 2018-03-06 09:52:59 -08:00
vmbus_drv.c