dmaengine: pch_dma: use tasklet_kill in teardown

As discussed in [1] the tasklet_disable is not a proper function for teardown.
We need to ensure irq is disabled, followed by ensuring that don't schedule any
more tasklets and then its safe to use tasklet_kill().

Here in pch dma driver we need to use free_irq() before tasklet_kill(). So move
up the free_irq() which will ensure that the irq is disabled and also wait till
all scheduled interrupts are executed by invoking synchronize_irq().

[1]: http://lwn.net/Articles/588457/

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/pch_dma.c b/drivers/dma/pch_dma.c
index 61fdc54a3c889d133058e046356d5b2f96bfeede..05fa548bd6595ac9fd63deb1200ddc0c595ef0d7 100644 (file)
--- a/drivers/dma/pch_dma.c
+++ b/drivers/dma/pch_dma.c
@@ -964,16 +964,16 @@ static void pch_dma_remove(struct pci_dev *pdev)
        if (pd) {
                dma_async_device_unregister(&pd->dma);
 
+               free_irq(pdev->irq, pd);
+
                list_for_each_entry_safe(chan, _c, &pd->dma.channels,
                                         device_node) {
                        pd_chan = to_pd_chan(chan);
 
-                       tasklet_disable(&pd_chan->tasklet);
                        tasklet_kill(&pd_chan->tasklet);
                }
 
                pci_pool_destroy(pd->pool);
-               free_irq(pdev->irq, pd);
                pci_iounmap(pdev, pd->membase);
                pci_release_regions(pdev);
                pci_disable_device(pdev);