On Mon, Mar 10, 2014 at 08:13:57PM +0100, Thomas Gleixner wrote: > > On Mon, 10 Mar 2014, Vinod Koul wrote: > > > As discussed in [1] the tasklet_disable is not a proper function for teardown. > > The driver also uses correct method of tasklet_kill. So remove tasklet_disable > > > > [1]: http://lwn.net/Articles/588457/ > > Please add an explanation why that driver is otherwise safe. sure... Adding below as changelog to this, pls let me know if you are okay with this ---- 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 at_hdmac driver we use free_irq() before tasklet_kill(). The free_irq() will ensure that the irq is disabled and also wait till all scheduled interrupts are executed by invoking synchronize_irq(). So we need to only do tasklet_kill() after invoking free_irq() [1]: http://lwn.net/Articles/588457/ -- ~Vinod > > > Reported-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > > Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx> > > --- > > drivers/dma/at_hdmac.c | 1 - > > 1 files changed, 0 insertions(+), 1 deletions(-) > > > > diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c > > index e2c04dc..c13a3bb 100644 > > --- a/drivers/dma/at_hdmac.c > > +++ b/drivers/dma/at_hdmac.c > > @@ -1569,7 +1569,6 @@ static int at_dma_remove(struct platform_device *pdev) > > > > /* Disable interrupts */ > > atc_disable_chan_irq(atdma, chan->chan_id); > > - tasklet_disable(&atchan->tasklet); > > > > tasklet_kill(&atchan->tasklet); > > list_del(&chan->device_node); > > -- > > 1.7.0.4 > > > > -- -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
