ath9k: Handle -ENOMEM on RX gracefully
ath9k: Handle -ENOMEM on RX gracefully

We would get an oops on RX on -ENOMEM by passing
NULL to the hardware on ath_rx_buf_link(). The oops
would look something like this:

ath_rx_tasklet+0x515/0x53b
ath9k_tasklet+0x48
tasklet_action
__do_softirq
irq_exit
do_IRQ

RIP: ath_rx_buf_link+0x3a

We correct this by handling the requeue directly on
the ath_rx_tasklet() and trying to allocate an skb
*prior* to sending up the last hardware processed
skb. If we run out of memory this gauranteees we have
skbs to work with while it simply drops new received
frames.

Signed-off-by: Luis R. Rodriguez <79e6b8107a8aa3944e09fad43634662ac3b91a0b@atheros.com>
Signed-off-by: John W. Linville <2a53bac7a5d324865ef46ec4c38b2c0fba1456b4@tuxdriver.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs