From ed66ba472a742cd8df37d7072804b2111cdb1014 Mon Sep 17 00:00:00 2001 From: Gertjan van Wingerde Date: Sat, 12 Nov 2011 19:10:44 +0100 Subject: [PATCH] rt2x00: Fix sleep-while-atomic bug in powersaving code. The generic powersaving code that determines after reception of a frame whether the device should go back to sleep or whether is could stay awake was calling rt2x00lib_config directly from RX tasklet context. On a number of the devices this call can actually sleep, due to having to confirm that the sleeping commands have been executed successfully. Fix this by moving the call to rt2x00lib_config to a workqueue call. This fixes bug https://bugzilla.redhat.com/show_bug.cgi?id=731672 Tested-by: Tomas Trnka Signed-off-by: Gertjan van Wingerde Cc: Acked-by: Ivo van Doorn Signed-off-by: John W. Linville --- drivers/net/wireless/rt2x00/rt2x00.h | 1 + drivers/net/wireless/rt2x00/rt2x00dev.c | 22 ++++++++++++++++++++-- 2 files changed, 21 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h index 2ec5c00235e..99ff12d0c29 100644 --- a/drivers/net/wireless/rt2x00/rt2x00.h +++ b/drivers/net/wireless/rt2x00/rt2x00.h @@ -943,6 +943,7 @@ struct rt2x00_dev { * Powersaving work */ struct delayed_work autowakeup_work; + struct work_struct sleep_work; /* * Data queue arrays for RX, TX, Beacon and ATIM. diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c index e1fb2a8569b..edd317fa7c0 100644 --- a/drivers/net/wireless/rt2x00/rt2x00dev.c +++ b/drivers/net/wireless/rt2x00/rt2x00dev.c @@ -465,6 +465,23 @@ static u8 *rt2x00lib_find_ie(u8 *data, unsigned int len, u8 ie) return NULL; } +static void rt2x00lib_sleep(struct work_struct *work) +{ + struct rt2x00_dev *rt2x00dev = + container_of(work, struct rt2x00_dev, sleep_work); + + if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags)) + return; + + /* + * Check again is powersaving is enabled, to prevent races from delayed + * work execution. + */ + if (!test_bit(CONFIG_POWERSAVING, &rt2x00dev->flags)) + rt2x00lib_config(rt2x00dev, &rt2x00dev->hw->conf, + IEEE80211_CONF_CHANGE_PS); +} + static void rt2x00lib_rxdone_check_ps(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb, struct rxdone_entry_desc *rxdesc) @@ -512,8 +529,7 @@ static void rt2x00lib_rxdone_check_ps(struct rt2x00_dev *rt2x00dev, cam |= (tim_ie->bitmap_ctrl & 0x01); if (!cam && !test_bit(CONFIG_POWERSAVING, &rt2x00dev->flags)) - rt2x00lib_config(rt2x00dev, &rt2x00dev->hw->conf, - IEEE80211_CONF_CHANGE_PS); + queue_work(rt2x00dev->workqueue, &rt2x00dev->sleep_work); } static int rt2x00lib_rxdone_read_signal(struct rt2x00_dev *rt2x00dev, @@ -1141,6 +1157,7 @@ int rt2x00lib_probe_dev(struct rt2x00_dev *rt2x00dev) INIT_WORK(&rt2x00dev->intf_work, rt2x00lib_intf_scheduled); INIT_DELAYED_WORK(&rt2x00dev->autowakeup_work, rt2x00lib_autowakeup); + INIT_WORK(&rt2x00dev->sleep_work, rt2x00lib_sleep); /* * Let the driver probe the device to detect the capabilities. @@ -1197,6 +1214,7 @@ void rt2x00lib_remove_dev(struct rt2x00_dev *rt2x00dev) */ cancel_work_sync(&rt2x00dev->intf_work); cancel_delayed_work_sync(&rt2x00dev->autowakeup_work); + cancel_work_sync(&rt2x00dev->sleep_work); if (rt2x00_is_usb(rt2x00dev)) { del_timer_sync(&rt2x00dev->txstatus_timer); cancel_work_sync(&rt2x00dev->rxdone_work); -- 2.41.0