[JAUNTY] UBUNTU: SAUCE: Added patch to ath5k driver: protect reset sequence by a spinlock

[Stefan Bader]

Tim Gardner wrote:
> Manoj Iyer wrote:
>> SRU JUSTIFICATION:
>>
>> IMPACT: ath5k driver hangs periodically
>> FIX: protect reset sequence by a spinlock
>> TEST: Both amd64 and i386 kernels in 
>> http://people.ubuntu.com/~manjo/lp356768-jaunty/
>> were tested.
>>
>> The following changes since commit 
>> a63b7d7beeaa1f8f33369cab6419831fa8991e40:
>>    Tyler Hicks (1):
>>          UBUNTU: SAUCE: (drop after 2.6.28) [PATCH] eCryptfs: Larger buffer 
>> for encrypted symlink targets
>>
>> are available in the git repository at:
>>
>>    git://kernel.ubuntu.com/manjo/ubuntu-jaunty.git lp356768
>>
>> Manoj Iyer (1):
>>        UBUNTU: SAUCE: Added patch to ath5k driver: protect reset sequence 
>> by a spinlock
>>
>>   drivers/net/wireless/ath5k/base.c |    6 ++++++
>>   drivers/net/wireless/ath5k/base.h |    1 +
>>   drivers/net/wireless/ath5k/phy.c  |    2 +-
>>   3 files changed, 8 insertions(+), 1 deletions(-)
>>
>>
>> From 9f03cfed8629c1e8cef710cf6d0ddc972ba38768 Mon Sep 17 00:00:00 2001
>> From: Manoj Iyer <manoj.iyer at canonical.com>
>> Date: Wed, 22 Apr 2009 13:41:11 -0500
>> Subject: [PATCH] UBUNTU: SAUCE: Added patch to ath5k driver: protect reset sequence by a spinlock
>>
>> OriginalAuthor: Bob Copeland <me at bobcopeland.com>
>>
>> Bug: #356768
>> BugLink: https://bugs.launchpad.net/linux/+bug/356768
>>
>> Signed-off-by: Manoj Iyer <manoj.iyer at canonical.com>
>> ---
>>   drivers/net/wireless/ath5k/base.c |    6 ++++++
>>   drivers/net/wireless/ath5k/base.h |    1 +
>>   drivers/net/wireless/ath5k/phy.c  |    2 +-
>>   3 files changed, 8 insertions(+), 1 deletions(-)
>>
>> diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c
>> index e521555..0f59b4d 100644
>> --- a/drivers/net/wireless/ath5k/base.c
>> +++ b/drivers/net/wireless/ath5k/base.c
>> @@ -525,6 +525,7 @@ ath5k_pci_probe(struct pci_dev *pdev,
>>   	sc->cachelsz = csz * sizeof(u32); /* convert to bytes */
>>   	sc->opmode = NL80211_IFTYPE_STATION;
>>   	mutex_init(&sc->lock);
>> +	spin_lock_init(&sc->restlock);
>>   	spin_lock_init(&sc->rxbuflock);
>>   	spin_lock_init(&sc->txbuflock);
>>   	spin_lock_init(&sc->block);
>> @@ -2665,6 +2666,7 @@ ath5k_reset(struct ath5k_softc *sc, bool stop, bool change_channel)
>>   {
>>   	struct ath5k_hw *ah = sc->ah;
>>   	int ret;
>> +	unsigned long flags;
>>
>>   	ATH5K_DBG(sc, ATH5K_DEBUG_RESET, "resetting\n");
>>
>> @@ -2673,7 +2675,11 @@ ath5k_reset(struct ath5k_softc *sc, bool stop, bool change_channel)
>>   		ath5k_txq_cleanup(sc);
>>   		ath5k_rx_stop(sc);
>>   	}
>> +
>> +	spin_lock_irqsave(&sc->restlock, flags);
>>   	ret = ath5k_hw_reset(ah, sc->opmode, sc->curchan, true);
>> +	spin_unlock_irqrestore(&sc->restlock, flags);
>> +
>>   	if (ret) {
>>   		ATH5K_ERR(sc, "can't reset hardware (%d)\n", ret);
>>   		goto err;
>> diff --git a/drivers/net/wireless/ath5k/base.h b/drivers/net/wireless/ath5k/base.h
>> index facc60d..bd08aae 100644
>> --- a/drivers/net/wireless/ath5k/base.h
>> +++ b/drivers/net/wireless/ath5k/base.h
>> @@ -152,6 +152,7 @@ struct ath5k_softc {
>>   				led_off;	/* off time for current blink */
>>
>>   	struct tasklet_struct	restq;		/* reset tasklet */
>> +	spinlock_t		restlock;	/* protects reset state */
>>
>>   	unsigned int		rxbufsize;	/* rx size based on mtu */
>>   	struct list_head	rxbuf;		/* receive buffer */
>> diff --git a/drivers/net/wireless/ath5k/phy.c b/drivers/net/wireless/ath5k/phy.c
>> index 35c7eb1..51e20d5 100644
>> --- a/drivers/net/wireless/ath5k/phy.c
>> +++ b/drivers/net/wireless/ath5k/phy.c
>> @@ -1620,7 +1620,7 @@ int ath5k_hw_rfregs(struct ath5k_hw *ah, struct ieee80211_channel *channel,
>>
>>   	if (ah->ah_rf_banks == NULL) {
>>   		/* XXX do extra checks? */
>> -		ah->ah_rf_banks = kmalloc(ah->ah_rf_banks_size, GFP_KERNEL);
>> +		ah->ah_rf_banks = kmalloc(ah->ah_rf_banks_size, GFP_ATOMIC);
>>   		if (ah->ah_rf_banks == NULL) {
>>   			ATH5K_ERR(ah->ah_sc, "out of memory\n");
>>   			return -ENOMEM;
> 
> This appears to be coming via stable updates. Shall we just wait and get
> it for free? If you can intercept this commit from 2.6.28.y before
> Stefan pulls from the stable tree, then just 'cherry-pick -x' it and add
> the Bug number so you get LP changelog bot goodness.
> 
> rtg

If I looked at this correctly this patch is neither in stables, nor in the 
current tree of Linux (have not checked tip-latest). It looks as it only exists 
on the upstream mailing list.

@manoj, as Tim said, please add the Bug (and BugLink too) headers.

Stefan
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