On Thu, May 23, 2013 at 01:51:29PM +0300, Andy Shevchenko wrote: > On Thu, May 23, 2013 at 1:09 PM, Vinod Koul <vinod.k...@intel.com> wrote: > > On Tue, May 21, 2013 at 08:24:15PM +0300, Andy Shevchenko wrote: > >> On Tue, May 21, 2013 at 6:11 PM, Will Deacon <will.dea...@arm.com> wrote: > >> > On Tue, May 21, 2013 at 01:33:17PM +0100, Andy Shevchenko wrote: > >> >> When thread is going to be stopped we have to unconditionally terminate > >> >> all > >> >> ongoing transfers. Otherwise it would be possible that callback > >> >> function will > >> >> be called on the next interrupt and will try to access to already freed > >> >> structures. > >> >> > >> >> The patch introduces specific error message for this, though it doesn't > >> >> increase the counter of the failed tests. > >> >> > >> > Thanks for persevering with this! Although this patch definitely fixes > >> > the > >> > panic I was seeing, I now observe buffer verification failures in > >> > subsequent > >> > test runs after an aborted run: > >> > >> I think the description to the commit adfa543e "dmatest: don't use > >> set_freezable_with_signal()" may shed light on this. > >> > >> The background (if I got it correctly) is in race with done flag. So, > >> we got a callback call from the DMA engine, but we don't know which > >> transfer triggers it. > >> I might be wrong. This is just an assumption. > >> > >> Have you ever see such behaviour on pre v3.10-rc1 kernels? (I mean > >> with old dmatest module) > > Terminate shouldnt cause the issue with buffer verfication, can you try > > this on > > dw_dmac, do you see similar failures on verfication? > > I saw the similar errors on dw_dmac on Intel Medfield device. Ah, so may not be a driver issue.
> Anyway, I checked another approach with Will. > For now I will send a quick fix that prevents tester to abort an > ongoing transfer. okay so taht should prevent regression, let me check on my setup if I find anything -- ~Vinod > In future we could implement a robust logic when transfers can be > interrupted at any time. > > -- > With Best Regards, > Andy Shevchenko -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
