[PATCH 6/11] drivers/dma: Correct NULL test

[Julia Lawall]

From: Julia Lawall <ju...@diku.dk>

cohd_fin has already been verified not to be NULL, so the argument to
BUG_ON cannot be true.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r@
expression *x;
expression e;
identifier l;
@@

if (x == NULL || ...) {
... when forall
return ...; }
... when != goto l;
when != x = e
when != &x
*x == NULL
// </smpl>

Signed-off-by: Julia Lawall <ju...@diku.dk>

---
drivers/dma/coh901318.c | 2 --
1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/coh901318.c b/drivers/dma/coh901318.c
index b5f2ee0..64a9372 100644
--- a/drivers/dma/coh901318.c
+++ b/drivers/dma/coh901318.c
@@ -613,8 +613,6 @@ static void dma_tasklet(unsigned long data)
cohd_fin->pending_irqs--;
cohc->completed = cohd_fin->desc.cookie;

- BUG_ON(cohc->nbr_active_done && cohd_fin == NULL);
-
if (cohc->nbr_active_done == 0)
return;

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[Dan Williams]

[ adding Linus in case this BUG_ON had a different intent, or can be deleted ]

[Linus Walleij]

[Dan/Julia]

> On Sat, Feb 6, 2010 at 1:43 AM, Julia Lawall <ju...@diku.dk> wrote:
> > From: Julia Lawall <ju...@diku.dk>
> >
> > cohd_fin has already been verified not to be NULL, so the
> argument to
> > BUG_ON cannot be true.

Acked-by: Linus Walleij <linus....@stericsson.com>

BTW I've got some more DMA patches for COH 901 318 and even
a client using it cooking, if you apply this I'll happily
rebase as soon as I can see it in -next.

Linus Walleij