Commits
Senthil Balasubramanian committed 19b9675069c
ath9k: Fix kernel panic caused by invalid rate index access. With the recent tx status optimization in mac80211, we bail out as and and when invalid rate index is found. So the behavior of resetting rate idx to -1 and count to 0 has changed for the rate indexes that were not part of the driver's retry series. This has resulted in ath9k using incorrect rate table index which caused the system to panic. Ideally ath9k need to loop only for the indexes that were part of the retry series and so simply use hw->max_rates as the loop counter. Pasted the stack trace of the panic issue for reference. [ 754.093192] BUG: unable to handle kernel paging request at ffff88046a9025b0 [ 754.093256] IP: [<ffffffffa02eac49>] ath_tx_status+0x209/0x2f0 [ath9k] [ 754.094888] Call Trace: [ 754.094903] <IRQ> [ 754.094928] [<ffffffffa051f883>] ieee80211_tx_status+0x203/0x9e0 [mac80211] [ 754.094975] [<ffffffffa053e305>] ? __ieee80211_wake_queue+0x125/0x140 [mac80211] [ 754.095017] [<ffffffffa02e66c9>] ath_tx_complete_buf+0x1b9/0x370 [ath9k] [ 754.095054] [<ffffffffa02e6fcf>] ath_tx_complete_aggr+0x51f/0xb50 [ath9k] [ 754.095098] [<ffffffffa05382a3>] ? ieee80211_prepare_and_rx_handle+0x173/0xab0 [mac80211] [ 754.095148] [<ffffffff81350e62>] ? _raw_spin_unlock_irqrestore+0x32/0x40 [ 754.095186] [<ffffffffa02e9735>] ath_tx_tasklet+0x365/0x4b0 [ath9k] [ 754.095224] [<ffffffff8107a2a2>] ? clockevents_program_event+0x62/0xa0 [ 754.095261] [<ffffffffa02e2628>] ath9k_tasklet+0x168/0x1c0 [ath9k] [ 754.095298] [<ffffffff8105599b>] tasklet_action+0x6b/0xe0 [ 754.095331] [<ffffffff81056278>] __do_softirq+0x98/0x120 [ 754.095361] [<ffffffff8100cd5c>] call_softirq+0x1c/0x30 [ 754.095393] [<ffffffff8100efb5>] do_softirq+0x65/0xa0 [ 754.095423] [<ffffffff810563fd>] irq_exit+0x8d/0x90 [ 754.095453] [<ffffffff8100ebc1>] do_IRQ+0x61/0xe0 [ 754.095482] [<ffffffff81351413>] ret_from_intr+0x0/0x15 [ 754.095513] <EOI> [ 754.095531] [<ffffffff81014375>] ? native_sched_clock+0x15/0x70 [ 754.096475] [<ffffffffa02bcfa6>] ? acpi_idle_enter_bm+0x24d/0x285 [processor] [ 754.096475] [<ffffffffa02bcf9f>] ? acpi_idle_enter_bm+0x246/0x285 [processor] [ 754.096475] [<ffffffff8127fab2>] cpuidle_idle_call+0x82/0x100 [ 754.096475] [<ffffffff8100a236>] cpu_idle+0xa6/0xf0 [ 754.096475] [<ffffffff81339bc1>] rest_init+0x91/0xa0 [ 754.096475] [<ffffffff814efccd>] start_kernel+0x3fd/0x408 [ 754.096475] [<ffffffff814ef347>] x86_64_start_reservations+0x132/0x136 [ 754.096475] [<ffffffff814ef451>] x86_64_start_kernel+0x106/0x115 [ 754.096475] RIP [<ffffffffa02eac49>] ath_tx_status+0x209/0x2f0 [ath9k] Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>