Re: [Regression] "iommu/amd: Relax locking in dma_ops path" makes tg3 ethernet transmit queue timeout

[Joerg Roedel]

On Mon, May 18, 2020 at 05:06:45PM +0800, Kai-Heng Feng wrote:
> Particularly, as soon as the spinlock is removed, the issue can be reproduced.
> Function domain_flush_complete() doesn't seem to affect the status.
> 
> However, the .map_page callback was removed by be62dbf554c5
> ("iommu/amd: Convert AMD iommu driver to the dma-iommu api"), so
> there's no easy revert for this issue.
> 
> This is still reproducible as of today's mainline kernel, v5.7-rc6.

Is there any error message from the IOMMU driver?