Attachment 591554 Details for Bug 811142 – backported fix for this issue

[patch] backported fix for this issue

0001-ath9k-Fix-softlockup-in-AR9485-backported.patch (text/plain), 2.60 KB, created by Mohammed Shafi on 2012-06-13 16:00:56 UTC

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Creator: Mohammed Shafi

Created: 2012-06-13 16:00:56 UTC

Size: 2.60 KB

patch

obsolete

>From c395856380dc351bab7262e4df96ecf456181fe6 Mon Sep 17 00:00:00 2001
>From: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
>Date: Wed, 13 Jun 2012 20:54:45 +0530
>Subject: [PATCH 3.0+] ath9k: Fix softlockup in AR9485(backported)
>
>Please note this is the backported version for the linux
>stable tree, while the patch for wireless-testing tree
>http://permalink.gmane.org/gmane.linux.kernel.wireless.general/92608
>
>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 [3.0+]
>Tested-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
>Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
>---
> drivers/net/wireless/ath/ath9k/main.c |    9 +++++++++
> 1 files changed, 9 insertions(+), 0 deletions(-)
>
>diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
>index 4de4473..41096f6 100644
>--- a/drivers/net/wireless/ath/ath9k/main.c
>+++ b/drivers/net/wireless/ath/ath9k/main.c
>@@ -971,6 +971,15 @@ void ath_hw_pll_work(struct work_struct *work)
> 					    hw_pll_work.work);
> 	u32 pll_sqsum;
> 
>+	/*
>+	 * 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 (!(sc->sc_flags & SC_OP_BEACONS))
>+		return;
>+
> 	if (AR_SREV_9485(sc->sc_ah)) {
> 
> 		ath9k_ps_wakeup(sc);
>-- 
>1.7.4.1
>

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Attachments on bug 811142: 576487 | 576533 | 577225 | 577370 | 577526 | 579744 | 591228 | 591554