kernel/iwlwifi-fix-PCI-E-transport-inta-race.patch
John W. Linville a43c59fbee mac80211: fix debugfs key->station symlink
brcmsmac: fix tx queue flush infinite loop
mac80211: Use the right headroom size for mesh mgmt frames
mac80211: fix work removal on deauth request
b43: add option to avoid duplicating device support with brcmsmac
mac80211: update oper_channel on ibss join
mac80211: set bss_conf.idle when vif is connected
iwlwifi: fix PCI-E transport "inta" race
2012-01-30 10:41:26 -05:00

52 lines
1.8 KiB
Diff

From b49ba04a3a0382e7314d990707c21094c410425a Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@intel.com>
Date: Thu, 19 Jan 2012 08:20:57 -0800
Subject: [PATCH 8/8] iwlwifi: fix PCI-E transport "inta" race
When an interrupt comes in, we read the reason
bits and collect them into "trans_pcie->inta".
This happens with the spinlock held. However,
there's a bug resetting this variable -- that
happens after the spinlock has been released.
This means that it is possible for interrupts
to be missed if the reset happens after some
other interrupt reasons were already added to
the variable.
I found this by code inspection, looking for a
reason that we sometimes see random commands
time out. It seems possible that this causes
such behaviour, but I can't say for sure right
now since it happens extremely infrequently on
my test systems.
Cc: stable@vger.kernel.org [3.2]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c
index 752493f..65d1f05 100644
--- a/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c
@@ -972,11 +972,11 @@ void iwl_irq_tasklet(struct iwl_trans *trans)
}
#endif
- spin_unlock_irqrestore(&trans->shrd->lock, flags);
-
/* saved interrupt in inta variable now we can reset trans_pcie->inta */
trans_pcie->inta = 0;
+ spin_unlock_irqrestore(&trans->shrd->lock, flags);
+
/* Now service all interrupt bits discovered above. */
if (inta & CSR_INT_BIT_HW_ERR) {
IWL_ERR(trans, "Hardware error detected. Restarting.\n");
--
1.7.4.4