Out of DMA space?

[Michal Kazior]

On 13 August 2015 at 01:16, Ben Greear <greearb at candelatech.com> wrote:
> I've been reloading the ath10k modules all afternoon, debugging issues
> in my CT firmware.  I've been unloading firmware with pkts queued
> in the TX logic, and they could easily not be flushable at this piont.
>
> I just saw this...and machine hung.
>
> DMA: Out of SW-IOMMU space for 1984 bytes at device 0000:05:00.0
> ath10k_pci 0000:05:00.0: failed to refill htt rx ring: -12
> DMA: Out of SW-IOMMU space for 1984 bytes at device 0000:06:00.0
> ath10k_pci 0000:06:00.0: failed to refill htt rx ring: -12
> DMA: Out of SW-IOMMU space for 2048 bytes at device 0000:07:00.0
> DMA: Out of SW-IOMMU space for 16 bytes at device 0000:07:00.0
>
> Just FYI really...I haven't seen this before.

I haven't seen anything like this before. Nevertheless this may
suggest there's an unbalanced DMA map-unmap in ath10k. I guess
unbalanced dma_pool and cohoerent DMA allocations combined with
kmemleak would've been detected earlier.


Michał