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    Subject[214/272] hostap_cs: fix sleeping function called from invalid context
    2.6.37-stable review patch.  If anyone has any objections, please let us know.

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

    From: Stanislaw Gruszka <sgruszka@redhat.com>

    commit 4e5518ca53be29c1ec3c00089c97bef36bfed515 upstream.

    pcmcia_request_irq() and pcmcia_enable_device() are intended
    to be called from process context (first function allocate memory
    with GFP_KERNEL, second take a mutex). We can not take spin lock
    and call them.

    It's safe to move spin lock after pcmcia_enable_device() as we
    still hold off IRQ until dev->base_addr is 0 and driver will
    not proceed with interrupts when is not ready.

    Patch resolves:
    https://bugzilla.redhat.com/show_bug.cgi?id=643758

    Reported-and-tested-by: rbugz@biobind.com
    Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
    Signed-off-by: John W. Linville <linville@tuxdriver.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    drivers/net/wireless/hostap/hostap_cs.c | 15 ++++++---------
    1 file changed, 6 insertions(+), 9 deletions(-)

    --- a/drivers/net/wireless/hostap/hostap_cs.c
    +++ b/drivers/net/wireless/hostap/hostap_cs.c
    @@ -518,22 +518,21 @@ static int prism2_config(struct pcmcia_d
    hw_priv->link = link;

    /*
    - * Make sure the IRQ handler cannot proceed until at least
    - * dev->base_addr is initialized.
    + * We enable IRQ here, but IRQ handler will not proceed
    + * until dev->base_addr is set below. This protect us from
    + * receive interrupts when driver is not initialized.
    */
    - spin_lock_irqsave(&local->irq_init_lock, flags);
    -
    ret = pcmcia_request_irq(link, prism2_interrupt);
    if (ret)
    - goto failed_unlock;
    + goto failed;

    ret = pcmcia_enable_device(link);
    if (ret)
    - goto failed_unlock;
    + goto failed;

    + spin_lock_irqsave(&local->irq_init_lock, flags);
    dev->irq = link->irq;
    dev->base_addr = link->resource[0]->start;
    -
    spin_unlock_irqrestore(&local->irq_init_lock, flags);

    local->shutdown = 0;
    @@ -546,8 +545,6 @@ static int prism2_config(struct pcmcia_d

    return ret;

    - failed_unlock:
    - spin_unlock_irqrestore(&local->irq_init_lock, flags);
    failed:
    kfree(hw_priv);
    prism2_release((u_long)link);



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