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    Subject[PATCH] b43legacy: Fix a sleep-in-atomic bug in b43legacy_attr_interfmode_store
    Date
    The driver may sleep under a spin lock, and the function call path is:
    b43legacy_attr_interfmode_store (acquire the lock by spin_lock_irqsave)
    b43legacy_radio_set_interference_mitigation
    b43legacy_radio_interference_mitigation_disable
    b43legacy_calc_nrssi_slope
    b43legacy_synth_pu_workaround
    might_sleep and msleep --> may sleep

    Fixing it may be complex, and a possible way is to remove
    spin_lock_irqsave and spin_lock_irqrestore in
    b43legacy_attr_interfmode_store, and the code has been protected by
    mutex_lock and mutex_unlock.

    Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
    ---
    drivers/net/wireless/broadcom/b43legacy/sysfs.c | 2 --
    1 file changed, 2 deletions(-)

    diff --git a/drivers/net/wireless/broadcom/b43legacy/sysfs.c b/drivers/net/wireless/broadcom/b43legacy/sysfs.c
    index 2a1da15..9ede143 100644
    --- a/drivers/net/wireless/broadcom/b43legacy/sysfs.c
    +++ b/drivers/net/wireless/broadcom/b43legacy/sysfs.c
    @@ -137,14 +137,12 @@ static ssize_t b43legacy_attr_interfmode_store(struct device *dev,
    }

    mutex_lock(&wldev->wl->mutex);
    - spin_lock_irqsave(&wldev->wl->irq_lock, flags);

    err = b43legacy_radio_set_interference_mitigation(wldev, mode);
    if (err)
    b43legacyerr(wldev->wl, "Interference Mitigation not "
    "supported by device\n");
    mmiowb();
    - spin_unlock_irqrestore(&wldev->wl->irq_lock, flags);
    mutex_unlock(&wldev->wl->mutex);

    return err ? err : count;
    --
    1.7.9.5

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