On Thu, Apr 29, 2021 at 10:34 AM Jianxiong Gao [off-list ref] wrote:

We observed several NVMe failures when running with SWIOTLB. The root
cause of the issue is that when data is mapped via SWIOTLB, the address
offset is not preserved. Several device drivers including the NVMe
driver relies on this offset to function correctly.

Even though we discovered the error when running using AMD SEV, we have
reproduced the same error in Rhel 8 without SEV. By adding swiotlb=force
option to the boot command line parameter, NVMe funcionality is
impacted. For example formatting a disk into xfs format returns an
error.

Christoph, are you OK with backporting this patch set to LTS, based on
the rationale in the cover letter above?
Thanks,
Marc