Re: BUG at drivers/iommu/amd_iommu.c:1436!

From: Joerg Roedel
Date: Mon Nov 21 2016 - 10:33:01 EST


On Fri, Nov 18, 2016 at 09:04:05AM -0500, Mark Hounschell wrote:
> OK. It's attached.

> [ 45.033715] WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:1158 check_unmap+0x4ef/0x990
> [ 45.037651] 3c59x 0000:04:04.0: DMA-API: device driver failed to check map error[device address=0x00000000ffedf840] [size=1536 bytes] [mapped as single]

Okay, there is a dma-debug warning from the 3c59x driver. Can you please
blacklist this driver (or compile it out) and re-try? The dma-debug code
will only show the first warning and stop then. So any possible warnings
from your out-of-tree driver will not be shown as long as the 3c59x
driver is loaded.

Alternativly you can write 1 to dma-api/all_errors in debug-fs so that
it will show all errors. But I suggest to unload the 3com driver first
and then load your driver.


Joerg