On Wed, May 05, 2021 at 09:23:28AM +0200, Greg KH wrote:

On Thu, Apr 29, 2021 at 05:33:06PM +0000, Jianxiong Gao wrote:

quoted

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.


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Changes in v2:
Rebased patches to 5.10.33

It looks like if I were to take these now, we need to also have a
version for 5.11.y because you can not upgrade from an older kernel and
have a "regression" like this, right?

5.11.y will still be alive for at least a week or so, let me see if your
backports work there or not...

Ok, looks like it worked, now queued up.

greg k-h