From: Felix Fietkau <nbd@openwrt.org>
Date: Sat, 10 Aug 2013 13:59:15 +0000 (+0200)
Subject: ath9k: fix rx descriptor related race condition
X-Git-Tag: v3.2.52~125
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=42cb87a101c3fd0e080e9605ee70275efdcc8280;p=pandora-kernel.git

ath9k: fix rx descriptor related race condition

commit e96542e55a2aacf4bdeccfe2f17b77c4895b4df2 upstream.

Similar to a race condition that exists in the tx path, the hardware
might re-read the 'next' pointer of a descriptor of the last completed
frame. This only affects non-EDMA (pre-AR93xx) devices.

To deal with this race, defer clearing and re-linking a completed rx
descriptor until the next one has been processed.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

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