This is very useful information; thank you. At this time I dd the entire image at provisioning time, and run the upgradable application from a loop-mounted image, so no update path involves writing many small files. However I intend to transition very soon to Yocto with package updates that are likely to make the problem visible again. At that time I'll actually be able to control the kernel configuration and source better than under debian, so if the problem is still present I'll see if I can propose a fix.
Peter On Tuesday, October 4, 2016 at 2:00:16 PM UTC-5, Matthijs van Duin wrote: > > I've also run into this once during an apt-get upgrade, leaving the system > in a pretty hosed state. I managed to recover it but it required a lot of > effort. Although evidently rare, this is clearly a very serious issue. > > The direct cause is edma_prep_slave_sg() failing to allocate memory for > the struct edma_desc. I don't know whether the kernel is genuinely out of > memory or if it simply cannot free it up immediately (the allocation is > done with GPF_ATOMIC), and whether this is because it is filled with a > backlog of writes or whether a leak of some sort is going on. > > Instead of deferring until memory is available, or even just proceeding > without DMA, the omap_hsmmc driver immediately fails the request with an > error, thus pretty much guaranteeing loss of data or even filesystem > corruption. I personally think this is completely unacceptable behaviour of > a block driver. > > I've been meaning to persue this matter on the linux-mmc and/or linux-omap > lists, but since it was a single isolated incident and I have lots of other > stuff to do I haven't been able to find the time and motivation yet. > > Matthijs > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/87073bfe-2138-4204-94cd-8c2427f8ff1b%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
