On 02/01/2018 07:19 PM, Devin Heitmueller wrote: > Hi Sakari, Hans, > > Do either of you have any thoughts on whether I'm actually leaking any > resources, or whether this is just a warning that doesn't have any > practical implication since I'm tearing down the videobuf2 queue? > > I don't really care about the embedded use case - do you see any > reason where at least for my local tree I cannot simply revert this > patch until a real solution is found? Drivers that use videobuf2-vmalloc are not affected by this since that doesn't implement the prepare/finish mem_ops. dma-contig and dma-sg are affected and syncing to/from device/cpu will be unbalanced, which could lead to corrupt frames. Although I think that given the situation that triggers this it is unlikely to be a real issue. In any case, em28xx/au0828 are OK. Regards, Hans > > Cheers, > > Devin > > On Mon, Jan 29, 2018 at 8:44 PM, Devin Heitmueller > <dheitmueller@xxxxxxxxxxxxxx> wrote: >> Hello Sakari, >> >> Thanks for taking the time to investigate. See comments inline. >> >> On Sun, Jan 28, 2018 at 5:23 PM, Sakari Ailus >> <sakari.ailus@xxxxxxxxxxxxxxx> wrote: >>> Hi Devin, >>> >>> On Sun, Jan 28, 2018 at 09:12:44AM -0500, Devin Heitmueller wrote: >>>> Hello all, >>>> >>>> I recently updated to the latest kernel, and I am seeing the following >>>> dumped to dmesg with both au0828 and em28xx based devices whenever I >>>> exit tvtime (my kernel is compiled with CONFIG_VIDEO_ADV_DEBUG=y by >>>> default): >>> >>> Thanks for reporting this. Would you be able to provide the full dmesg, >>> with VB2 debug parameter set to 2? >> >> Output can be found at https://pastebin.com/nXS7MTJH >> >>> I can't immediately see how you'd get this, well, without triggering a >>> kernel warning or two. The code is pretty complex though. >> >> If this is something I screwed up when I did the VB2 port for em28xx >> several years ago, point me in the right direction and I'll see what I >> can do. However given we're seeing it with multiple drivers, this >> feels like some subtle issue inside videobuf2. >> >> Devin >> >> -- >> Devin J. Heitmueller - Kernel Labs >> http://www.kernellabs.com > > >
