summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>2012-06-12 20:13:43 +0530
committerJohn W. Linville <linville@tuxdriver.com>2012-06-13 14:35:57 -0400
commit64bc1239c790e051ff677e023435d770d2ffa174 (patch)
tree6f71de3e35854e623bea91f29c171a54453e20b5
parenta197b76c230725962dc8e13102b24468e8621bfb (diff)
ath9k: Fix softlockup in AR9485
steps to recreate: load latest ath9k driver with AR9485 stop the network-manager and wpa_supplicant bring the interface up Call Trace: [<ffffffffa0517490>] ? ath_hw_check+0xe0/0xe0 [ath9k] [<ffffffff812cd1e8>] __const_udelay+0x28/0x30 [<ffffffffa03bae7a>] ar9003_get_pll_sqsum_dvc+0x4a/0x80 [ath9k_hw] [<ffffffffa05174eb>] ath_hw_pll_work+0x5b/0xe0 [ath9k] [<ffffffff810744fe>] process_one_work+0x11e/0x470 [<ffffffff8107530f>] worker_thread+0x15f/0x360 [<ffffffff810751b0>] ? manage_workers+0x230/0x230 [<ffffffff81079af3>] kthread+0x93/0xa0 [<ffffffff815fd3a4>] kernel_thread_helper+0x4/0x10 [<ffffffff81079a60>] ? kthread_freezable_should_stop+0x70/0x70 [<ffffffff815fd3a0>] ? gs_change+0x13/0x13 ensure that the PLL-WAR for AR9485/AR9340 is executed only if the STA is associated (or) IBSS/AP mode had started beaconing. Ideally this WAR is needed to recover from some rare beacon stuck during stress testing. Before the STA is associated/IBSS had started beaconing, PLL4(0x1618c) always seem to have zero even though we had configured PLL3(0x16188) to query about PLL's locking status. When we keep on polling infinitely PLL4's 8th bit(ie check for PLL locking measurements is done), machine hangs due to softlockup. fixes https://bugzilla.redhat.com/show_bug.cgi?id=811142 Reported-by: Rolf Offermanns <rolf.offermanns@gmx.net> Cc: stable@vger.kernel.org Tested-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
-rw-r--r--drivers/net/wireless/ath/ath9k/link.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/ath9k/link.c b/drivers/net/wireless/ath/ath9k/link.c
index 0cc4c70f7f0c..a105c9426251 100644
--- a/drivers/net/wireless/ath/ath9k/link.c
+++ b/drivers/net/wireless/ath/ath9k/link.c
@@ -136,6 +136,14 @@ void ath_hw_pll_work(struct work_struct *work)
u32 pll_sqsum;
struct ath_softc *sc = container_of(work, struct ath_softc,
hw_pll_work.work);
+ /*
+ * ensure that the PLL WAR is executed only
+ * after the STA is associated (or) if the
+ * beaconing had started in interfaces that
+ * uses beacons.
+ */
+ if (!test_bit(SC_OP_BEACONS, &sc->sc_flags))
+ return;
ath9k_ps_wakeup(sc);
pll_sqsum = ar9003_get_pll_sqsum_dvc(sc->sc_ah);