bna: Add synchronization for tx ring.

2017-07-04T09:51:28+00:00

commit d667f78514c656a6a8bf0b3d6134a7fe5cd4d317 upstream. We received two reports of BUG_ON in bnad_txcmpl_process() where hw_consumer_index appeared to be ahead of producer_index. Out of order write/read of these variables could explain these reports. bnad_start_xmit(), as a producer of tx descriptors, has a few memory barriers sprinkled around writes to producer_index and the device's doorbell but they're not paired with anything in bnad_txcmpl_process(), a consumer. Since we are synchronizing with a device, we must use mandatory barriers, not smp_*. Also, I didn't see the purpose of the last smp_mb() in bnad_start_xmit(). Signed-off-by: Benjamin Poirier Signed-off-by: David S. Miller Signed-off-by: Willy Tarreau

first commit

2016-08-15T02:19:42+00:00

xavi/android_kernel_m2note/drivers/net/ethernet/brocade, branch ng-7.1.2

bna: Add synchronization for tx ring.

first commit