On Wed, Feb 19, 2020 at 10:17 AM Vinod Koul <vkoul@xxxxxxxxxx> wrote:
> On 17-02-20, 23:24, Geert Uytterhoeven wrote:
> > On Mon, Feb 17, 2020 at 3:41 PM Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
> > > The caller is already holding the lock so this will deadlock.
> > >
> > > Fixes: 0b58828c923e ("DMAENGINE: COH 901 318 remove irq counting")
> > > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > > ---
> > > This is the second double lock bug found using static analysis. The
> > > previous one was commit 627469e4445b ("dmaengine: coh901318: Fix a
> > > double-lock bug").
> > >
> > > The fact that this has been broken for ten years suggests that no one
> > > has the hardware.
> >
> > Or this only runs CONFIG_SMP=n kernels?
> > This seems to be used in arch/arm/boot/dts/ste-u300.dts only, and
> > CONFIG_ARCH_U300 is a ARCH_MULTI_V5 platform, which looks like
> > it doesn't support SMP?
>
> Should we drop the driver then..?
I still have the hardware and it still works if that is the question :D
And yeah it only has one CPU, but still has a DMA engine.
The patch is fine to apply because it fixes a bug, should the same
hardware block be used on SMP.
Yours,
Linus Walleij
