[patch 03/22] ath5k: fix suspend-related oops on rmmod

From: Greg KH
Date: Sat Nov 15 2008 - 00:26:15 EST


2.6.27-stable review patch. If anyone has any objections, please let us know.

------------------

From: Elias Oltmanns <eo@xxxxxxxxxxxxxx>

Cumulative patch backporting the following two commits from upstream:

commit 8bdd5b9c6bd53add260756b6673a0545fbdbba21 upstream
Author: Bob Copeland <me@xxxxxxxxxxxxxxx>

Based on a patch by Elias Oltmanns, we call ath5k_init in resume even
if we didn't previously open the device. Besides starting up the
device unnecessarily, this also causes an oops on rmmod because
mac80211 will not invoke ath5k_stop and softirqs are left running after
the module has been unloaded. Add a new state bit, ATH_STAT_STARTED,
to indicate that we have been started up.

commit bc1b32d6bdd2d6f3fbee9a7c01c9b099f11c579c upstream
Author: Elias Oltmanns <eo@xxxxxxxxxxxxxx>

After a s2ram / resume cycle, resetting the key cache does not work
unless it is deferred until after the hardware has been reinitialised by
a call to ath5k_hw_reset(). This fixes a regression introduced by
"ath5k: fix suspend-related oops on rmmod".

Reported-by: Toralf Förster <toralf.foerster@xxxxxx>
Signed-off-by: Elias Oltmanns <eo@xxxxxxxxxxxxxx>
Signed-off-by: Bob Copeland <me@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>


---
drivers/net/wireless/ath5k/base.c | 67 +++++++++++++++++++-------------------
drivers/net/wireless/ath5k/base.h | 3 +
2 files changed, 36 insertions(+), 34 deletions(-)

--- a/drivers/net/wireless/ath5k/base.c
+++ b/drivers/net/wireless/ath5k/base.c
@@ -294,9 +294,9 @@ static inline u64 ath5k_extend_tsf(struc
}

/* Interrupt handling */
-static int ath5k_init(struct ath5k_softc *sc);
+static int ath5k_init(struct ath5k_softc *sc, bool is_resume);
static int ath5k_stop_locked(struct ath5k_softc *sc);
-static int ath5k_stop_hw(struct ath5k_softc *sc);
+static int ath5k_stop_hw(struct ath5k_softc *sc, bool is_suspend);
static irqreturn_t ath5k_intr(int irq, void *dev_id);
static void ath5k_tasklet_reset(unsigned long data);

@@ -584,7 +584,7 @@ ath5k_pci_suspend(struct pci_dev *pdev,

ath5k_led_off(sc);

- ath5k_stop_hw(sc);
+ ath5k_stop_hw(sc, true);

free_irq(pdev->irq, sc);
pci_save_state(pdev);
@@ -599,8 +599,7 @@ ath5k_pci_resume(struct pci_dev *pdev)
{
struct ieee80211_hw *hw = pci_get_drvdata(pdev);
struct ath5k_softc *sc = hw->priv;
- struct ath5k_hw *ah = sc->ah;
- int i, err;
+ int err;

pci_restore_state(pdev);

@@ -621,21 +620,11 @@ ath5k_pci_resume(struct pci_dev *pdev)
goto err_no_irq;
}

- err = ath5k_init(sc);
+ err = ath5k_init(sc, true);
if (err)
goto err_irq;
ath5k_led_enable(sc);

- /*
- * Reset the key cache since some parts do not
- * reset the contents on initial power up or resume.
- *
- * FIXME: This may need to be revisited when mac80211 becomes
- * aware of suspend/resume.
- */
- for (i = 0; i < AR5K_KEYTABLE_SIZE; i++)
- ath5k_hw_reset_key(ah, i);
-
return 0;
err_irq:
free_irq(pdev->irq, sc);
@@ -657,7 +646,6 @@ ath5k_attach(struct pci_dev *pdev, struc
struct ath5k_softc *sc = hw->priv;
struct ath5k_hw *ah = sc->ah;
u8 mac[ETH_ALEN];
- unsigned int i;
int ret;

ATH5K_DBG(sc, ATH5K_DEBUG_ANY, "devid 0x%x\n", pdev->device);
@@ -676,13 +664,6 @@ ath5k_attach(struct pci_dev *pdev, struc
__set_bit(ATH_STAT_MRRETRY, sc->status);

/*
- * Reset the key cache since some parts do not
- * reset the contents on initial power up.
- */
- for (i = 0; i < AR5K_KEYTABLE_SIZE; i++)
- ath5k_hw_reset_key(ah, i);
-
- /*
* Collect the channel list. The 802.11 layer
* is resposible for filtering this list based
* on settings like the phy mode and regulatory
@@ -2197,12 +2178,18 @@ ath5k_beacon_config(struct ath5k_softc *
\********************/

static int
-ath5k_init(struct ath5k_softc *sc)
+ath5k_init(struct ath5k_softc *sc, bool is_resume)
{
- int ret;
+ struct ath5k_hw *ah = sc->ah;
+ int ret, i;

mutex_lock(&sc->lock);

+ if (is_resume && !test_bit(ATH_STAT_STARTED, sc->status))
+ goto out_ok;
+
+ __clear_bit(ATH_STAT_STARTED, sc->status);
+
ATH5K_DBG(sc, ATH5K_DEBUG_RESET, "mode %d\n", sc->opmode);

/*
@@ -2220,7 +2207,7 @@ ath5k_init(struct ath5k_softc *sc)
*/
sc->curchan = sc->hw->conf.channel;
sc->curband = &sc->sbands[sc->curchan->band];
- ret = ath5k_hw_reset(sc->ah, sc->opmode, sc->curchan, false);
+ ret = ath5k_hw_reset(ah, sc->opmode, sc->curchan, false);
if (ret) {
ATH5K_ERR(sc, "unable to reset hardware: %d\n", ret);
goto done;
@@ -2229,7 +2216,14 @@ ath5k_init(struct ath5k_softc *sc)
* This is needed only to setup initial state
* but it's best done after a reset.
*/
- ath5k_hw_set_txpower_limit(sc->ah, 0);
+ ath5k_hw_set_txpower_limit(ah, 0);
+
+ /*
+ * Reset the key cache since some parts do not reset the
+ * contents on initial power up or resume from suspend.
+ */
+ for (i = 0; i < AR5K_KEYTABLE_SIZE; i++)
+ ath5k_hw_reset_key(ah, i);

/*
* Setup the hardware after reset: the key cache
@@ -2249,13 +2243,17 @@ ath5k_init(struct ath5k_softc *sc)
AR5K_INT_RXORN | AR5K_INT_FATAL | AR5K_INT_GLOBAL |
AR5K_INT_MIB;

- ath5k_hw_set_intr(sc->ah, sc->imask);
+ ath5k_hw_set_intr(ah, sc->imask);
+
+ __set_bit(ATH_STAT_STARTED, sc->status);
+
/* Set ack to be sent at low bit-rates */
- ath5k_hw_set_ack_bitrate_high(sc->ah, false);
+ ath5k_hw_set_ack_bitrate_high(ah, false);

mod_timer(&sc->calib_tim, round_jiffies(jiffies +
msecs_to_jiffies(ath5k_calinterval * 1000)));

+out_ok:
ret = 0;
done:
mmiowb();
@@ -2310,7 +2308,7 @@ ath5k_stop_locked(struct ath5k_softc *sc
* stop is preempted).
*/
static int
-ath5k_stop_hw(struct ath5k_softc *sc)
+ath5k_stop_hw(struct ath5k_softc *sc, bool is_suspend)
{
int ret;

@@ -2341,6 +2339,9 @@ ath5k_stop_hw(struct ath5k_softc *sc)
}
}
ath5k_txbuf_free(sc, sc->bbuf);
+ if (!is_suspend)
+ __clear_bit(ATH_STAT_STARTED, sc->status);
+
mmiowb();
mutex_unlock(&sc->lock);

@@ -2719,12 +2720,12 @@ err:

static int ath5k_start(struct ieee80211_hw *hw)
{
- return ath5k_init(hw->priv);
+ return ath5k_init(hw->priv, false);
}

static void ath5k_stop(struct ieee80211_hw *hw)
{
- ath5k_stop_hw(hw->priv);
+ ath5k_stop_hw(hw->priv, false);
}

static int ath5k_add_interface(struct ieee80211_hw *hw,
--- a/drivers/net/wireless/ath5k/base.h
+++ b/drivers/net/wireless/ath5k/base.h
@@ -132,11 +132,12 @@ struct ath5k_softc {
size_t desc_len; /* size of TX/RX descriptors */
u16 cachelsz; /* cache line size */

- DECLARE_BITMAP(status, 4);
+ DECLARE_BITMAP(status, 5);
#define ATH_STAT_INVALID 0 /* disable hardware accesses */
#define ATH_STAT_MRRETRY 1 /* multi-rate retry support */
#define ATH_STAT_PROMISC 2
#define ATH_STAT_LEDSOFT 3 /* enable LED gpio status */
+#define ATH_STAT_STARTED 4 /* opened & irqs enabled */

unsigned int filter_flags; /* HW flags, AR5K_RX_FILTER_* */
unsigned int curmode; /* current phy mode */

--
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