From: Dan Williams Date: Tue, 14 Jul 2009 20:38:29 +0000 (-0700) Subject: iop-adma: fix lockdep false positive X-Git-Tag: v2.6.32-rc1~60^2^2~14^2~2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=72be12f0c39df46832403cbfd82e132a883f5ddc;p=profile%2Fivi%2Fkernel-adaptation-intel-automotive.git iop-adma: fix lockdep false positive lockdep correctly identifies a potential recursive locking case for iop_chan->lock, but in the dependency submission case we expect that the same class will be acquired for both the parent dependency and the child channel. Signed-off-by: Dan Williams --- diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c index ce45f3f..9c752bd 100644 --- a/drivers/dma/iop-adma.c +++ b/drivers/dma/iop-adma.c @@ -288,7 +288,12 @@ static void iop_adma_tasklet(unsigned long data) { struct iop_adma_chan *iop_chan = (struct iop_adma_chan *) data; - spin_lock(&iop_chan->lock); + /* lockdep will flag depedency submissions as potentially + * recursive locking, this is not the case as a dependency + * submission will never recurse a channels submit routine. + * There are checks in async_tx.c to prevent this. + */ + spin_lock_nested(&iop_chan->lock, SINGLE_DEPTH_NESTING); __iop_adma_slot_cleanup(iop_chan); spin_unlock(&iop_chan->lock); }