Bug 1997720

1. Please describe the problem:
A kernel bug was reported that impacts Fedora 34 when using serial communication over USB. This is meant as a tracker to ensure the git reversal impacts Fedora 34 and not just Rawhide.

2. What is the Version-Release number of the kernel:
5.10.* - see kernel.org BZ https://bugzilla.kernel.org/show_bug.cgi?id=214131

3. Did it work previously in Fedora? If so, what kernel version did the issue
   *first* appear?  Old kernels are available for download at
   https://koji.fedoraproject.org/koji/packageinfo?packageID=8 :

Yes - this was a recent kernel change that is being reverted. 

4. Can you reproduce this issue? If so, please provide the steps to reproduce
   the issue below:

Use esptool.py (part of Arduino for instance) to communicate with a USB device using the serial protocol, and it fails. The kernel is not passing in responses from the client/unit.


5. Does this problem occur with the latest Rawhide kernel? To install the
   Rawhide kernel, run ``sudo dnf install fedora-repos-rawhide`` followed by
   ``sudo dnf update --enablerepo=rawhide kernel``:

Unknown - but I would assume so since the BZ is confirmed on the kernel.

6. Are you running any modules that not shipped with directly Fedora's kernel?:

No.

7. Please attach the kernel logs. You can get the complete kernel log
   for a boot with ``journalctl --no-hostname -k > dmesg.txt``. If the
   issue occurred on a previous boot, use the journalctl ``-b`` flag.

See attached BZ.