tree 44551edf737386ad546046171d0ac2dc3b972283
parent 260e695196de8b91bbab482d3804e4e0312a59b6
author Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com> 1395063265 +0200
committer John W. Linville <linville@tuxdriver.com> 1395078259 -0400

wil6210: fix race between disconnect and Tx NAPI

When disconnecting some CID, corresponded Tx vring get released. During vring
release, all descriptors get freed. It is possible that Tx NAPI working on the same
vring simultaneously. If it happens, descriptor may be double freed.

To protect from the race above, make sure NAPI won't process the same vring.
Introduce 'enabled' flag in the struct vring_tx_data. Proceed with Tx NAPI only if
'enabled' flag set. Prior to Tx vring release, clear this flag and make sure NAPI
get synchronized.

NAPI enablement status protected by wil->mutex, add protection where it was
missing and check for it.

During reset, disconnect all peers first, then proceed with the Rx vring. It allows for
the disconnect flow to observe proper 'wil->status' and correctly notify cfg80211 about
connection status change

Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>