On 2017-03-27 15:01, Andreas Kölbl wrote: > Hey guys, > > I try to measure the subpaging overhead on the jetson-tk1 and stumbled > over a jailhouse warning I don't know how to interpret. > "WARNING: Overflow during MMIO region registration!" jailhouse prints > out to console after disabling. > > It appears if (cell->num_mmio_regions >= cell->max_mmio_regions) is true > and I don't know where those variables come from. > > Steps to reproduce: > Add a memory region with size 0x100 to your non-root cell configuration. > load, start, disable jailhouse
When you create a cell which hands out a sub-set of an MMIO region previously owned by another cell, the cell must have created its MMIO regions already sub-paged. Otherwise, the need to split an existing page comes "as a surprise" to that cell, and it will fail to do so due to missing resources. IOW: Configure the root cell having two sub-page regions describing a single MMIO page if one of that regions shall later on be handed out to a non-root cell. This is different from the transparent splitting/ unification of potential hugepages in the memory mapping. Jan -- Siemens AG, Corporate Technology, CT RDA ITP SES-DE Corporate Competence Center Embedded Linux -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
