Source: linux Version: 5.10.28-1 Followup-For: Bug #986995 I can confirm any device controlled by the acm driver has issues starting with 5.10.28. Sometimes it's possible to just replug the serial device to fix the issue, however for devices that reconnect after reset, there's no work-around.
These include most MCU boards, such as arduino. Downgrading to 5.10.0-6 (5.10.26-1) fixes the issue. Relevant upstream bug reports: https://bugzilla.kernel.org/show_bug.cgi?id=212751 https://bugzilla.kernel.org/show_bug.cgi?id=212725
