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    Subject[patch 20/27] hvc_console: Fix free_irq in spinlocked section
    2.6.27-stable review patch.  If anyone has any objections, please let us 
    know.

    ------------------
    From: Christian Borntraeger <borntraeger@de.ibm.com>

    commit eef2622a9fcfa964073333ea72c7c9cd20ad45e6 upstream

    hvc_console: Fix free_irq in spinlocked section

    commit 611e097d7707741a336a0677d9d69bec40f29f3d
    Author: Christian Borntraeger <borntraeger@de.ibm.com>
    hvc_console: rework setup to replace irq functions with callbacks
    introduced a spinlock recursion problem. The notifier_del is
    called with a lock held, and in turns calls free_irq which then
    complains when manipulating procfs. This fixes it by moving the
    call to the notifier to outside of the locked section.

    Signed-off-by: Christian Borntraeger<borntraeger@de.ibm.com>
    Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    drivers/char/hvc_console.c | 10 +++++-----
    1 file changed, 5 insertions(+), 5 deletions(-)

    --- a/drivers/char/hvc_console.c
    +++ b/drivers/char/hvc_console.c
    @@ -367,13 +367,13 @@ static void hvc_close(struct tty_struct
    spin_lock_irqsave(&hp->lock, flags);

    if (--hp->count == 0) {
    - if (hp->ops->notifier_del)
    - hp->ops->notifier_del(hp, hp->data);
    -
    /* We are done with the tty pointer now. */
    hp->tty = NULL;
    spin_unlock_irqrestore(&hp->lock, flags);

    + if (hp->ops->notifier_del)
    + hp->ops->notifier_del(hp, hp->data);
    +
    /*
    * Chain calls chars_in_buffer() and returns immediately if
    * there is no buffered data otherwise sleeps on a wait queue
    @@ -416,11 +416,11 @@ static void hvc_hangup(struct tty_struct
    hp->n_outbuf = 0;
    hp->tty = NULL;

    + spin_unlock_irqrestore(&hp->lock, flags);
    +
    if (hp->ops->notifier_del)
    hp->ops->notifier_del(hp, hp->data);

    - spin_unlock_irqrestore(&hp->lock, flags);
    -
    while(temp_open_count) {
    --temp_open_count;
    kref_put(&hp->kref, destroy_hvc_struct);
    --


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