On 19-02-20, 10:20, Geert Uytterhoeven wrote:
> Hi Vinod,
>
> On Wed, Feb 19, 2020 at 10:18 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..?
>
> Why? Because spinlocks are no-ops on SMP=n, and spinlock bugs thus don't
> affect the single platform using the driver?
That doesn't answer the question if anyone has a hardware and we have
users :)
Sorry I should have written better about hardware and testing
rather than cryptic reply which may have suggested about SMP :)
--
~Vinod
