On 2019-06-17 at 09:27 -0400, Sven Van Asbroeck wrote:
> Hello Robin,
>
> On Sun, Jun 16, 2019 at 10:02 PM Robin Gong <yibin.gong@xxxxxxx>
> wrote:
> >
> >
> > The default imx defconfig and dts should be ok, because firmware
> > load
> > is delayed after rootfs mounted where firmware located in and
> > before
> > that, some driver which use sdma such as spi/uart/audio may have
> > already enable sdma clock which means channel0 interrupt could be
> > cleared immediately without interrupt storm. That's why I can't
> > reproduce your issue at first, but catch it once I sync with your
> > directly firmware load defconfig. So seems not very must to CC
> > stable
> > tree?
> As far as I know, the bug/crash does not happen if you're loading the
> sdma firmware from a filesystem. So the vast majority of users would
> never see the crash.
>
> I agree that this is not a high-priority bugfix. But it's worthwhile
> for the
> stable trees to have it.
>
> >
> > Yes, but Michael's patch is the right direction, at least it fix RT
> > case and meaningless channel0 interrupt storm coming before
> > clearing
> > channel0 interrupt status in sdma_run_channel0(). Now, this patch
> > could
> > fix its minor side-effect.
> I'm not suggesting that we should revert or change Michael's patch.
> Just
> that it would be good for the v2 patch to contain:
>
> Fixes: 1d069bfa3c78 ("dmaengine: imx-sdma: ack channel 0 IRQ in the
> interrupt handler")
>
> This should allow stable maintainers to pull in your patch if and
> only if
> their release already contains 1d069bfa3c78.
Okay, would add Fixes tag into v2.
