Hi On 27.12.2024 23.59, Forest wrote:
#regzbot introduced: 63a1f8454962 Dear maintainer, I think I have found a regression in kernels version 6.10 and newer, including the latest mainline v6.13-rc4: fastboot (the tool for communicating with Android bootloaders) now fails to perform various operations over USB. The problem manifests as an error when attempting to 'fastboot flash' an image (e.g. a new kernel containing security updates) to a LineageOS phone. It also manifests with simpler operations like reading a variable from the bootloader. For example: fastboot getvar kernel A typical error message when the failure occurs: getvar:kernel FAILED (remote: 'GetVar Variable Not found') I can reproduce this at will. It happens about 50% of the time when I run the above getvar command, and almost all the time when I try to push a new kernel to a device. A git bisect reveals this: 63a1f8454962a64746a59441687dc2401290326c is the first bad commit commit 63a1f8454962a64746a59441687dc2401290326c Author: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Date: Mon Apr 29 17:02:28 2024 +0300 xhci: stored cached port capability values in one place
It's not clear to me why this patch would cause regression. Could you enable xhci and usb core dynamic debug before connecting the device, and then share dmesg after the issue is triggered. dmesg of a working case would also be good to have for comparison. mount -t debugfs none /sys/kernel/debug echo 'module xhci_hcd =p' >/sys/kernel/debug/dynamic_debug/control echo 'module usbcore =p' >/sys/kernel/debug/dynamic_debug/control < Reproduce issue > Send output of dmesg Thanks Mathias