Since it's a regression, would it be possible for you to do a kernel bisection?
First, find the last -rc kernel works and the first -rc kernel doesn’t work from http://kernel.ubuntu.com/~kernel-ppa/mainline/ Then, $ sudo apt build-dep linux $ git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git $ cd linux $ git bisect start $ git bisect good $(the working version you found) $ git bisect bad $(the non-working version found) $ make localmodconfig $ make -j`nproc` deb-pkg Install the newly built kernel, then reboot with it. If it still have the same issue, $ git bisect bad Otherwise, $ git bisect good Repeat to "make -j`nproc` deb-pkg" until you find the offending commit. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1886172 Title: high speed data to usb disk makes the kernel think that is has been unmounted Status in linux package in Ubuntu: Confirmed Bug description: Description: When the speed of data with a usb disk device is too high, the probes that check if the disk still exists is missed. This makes the disk to be unmounted and is remounted with an other drive letter (/dev/sdX). If this disk is the root ("/"), the computer hangs. A usb SSD-disk (4 TB) connected to a USB port reproduce this bug easily. This has never happened with a mechanical USB-drive. Symptoms and how to reproduce: 1) (Disk mounted as root) Computer hangs. Only way to get started again is a hard reset. 2) (Erasing disk, not mounted as root) If you erase a disk with dd ("dd if=/dev/zero of=/dev/sdX"), the disk disappears from the mounted list and reappears as an other drive letter. In my case the data is redirected to /dev/null and the fans speed up. The apparent data transfer speed is also increased. Usually this happens after about 45 to 60 minutes. 3) Fill RAM with programs and make sure the swap to this disk is used. Bug found in: $ uname -a Linux pb-189b1884 5.4.0-40-generic #44-Ubuntu SMP Tue Jun 23 00:01:04 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux $ cat /proc/version_signature Ubuntu 5.4.0-40.44-generic 5.4.44 Bug not found in: Linux v4.15 (Ubuntu Bionic) Hardware: Tested with slower and faster computers. Tested directly connected to a computer and via a hub. They all reproduce this bug. Workaround: None found. --- ProblemType: Bug ApportVersion: 2.20.11-0ubuntu27.3 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: user 6813 F.... pulseaudio /dev/snd/controlC0: user 6813 F.... pulseaudio CasperMD5CheckResult: skip CurrentDesktop: MATE DistroRelease: Ubuntu 20.04 MachineType: ASUSTeK COMPUTER INC. GL503VM NonfreeKernelModules: nvidia_modeset nvidia Package: linux (not installed) ProcFB: 0 EFI VGA ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-5.4.0-40-generic root=UUID=74545cc2-bc7e-11ea-9c1b-6b408850adf5 ro fsck.repair=yes ProcVersionSignature: Ubuntu 5.4.0-40.44-generic 5.4.44 RelatedPackageVersions: linux-restricted-modules-5.4.0-40-generic N/A linux-backports-modules-5.4.0-40-generic N/A linux-firmware 1.187.1 Tags: focal Uname: Linux 5.4.0-40-generic x86_64 UnreportableReason: This report is about a package that is not installed. UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: sudo vboxusers wireshark WifiSyslog: _MarkForUpload: False dmi.bios.date: 04/29/2019 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: GL503VM.314 dmi.board.asset.tag: ATN12345678901234567 dmi.board.name: GL503VM dmi.board.vendor: ASUSTeK COMPUTER INC. dmi.board.version: 1.0 dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: ASUSTeK COMPUTER INC. dmi.chassis.version: 1.0 dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrGL503VM.314:bd04/29/2019:svnASUSTeKCOMPUTERINC.:pnGL503VM:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnGL503VM:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0: dmi.product.family: ROG dmi.product.name: GL503VM dmi.product.version: 1.0 dmi.sys.vendor: ASUSTeK COMPUTER INC. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1886172/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp