Thanks for your advice! I've posted a bug report upstream: http://permalink.gmane.org/gmane.linux.usb.general/129790
I also checked out some older kernels. The problem is present since 3.18, while 3.17.x was OK. Or rather, had other, less dramatic problems on the machine. ** Tags added: kernel-bug-reported-upstream -- 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/1485057 Title: "lsusb -v" as root freezes the kernel on Acer ES1-111 Status in linux package in Ubuntu: Triaged Bug description: reproducible: always Steps to reproduce: - open a terminal - sudo bash - lsusb -v In a virtual terminal, the command prints the name of the first device it finds, then the system freezes completely. In a terminal of the desktop, I don't even get the name of the device, the system freezes immediately. Either way, I have to power off the machine. There is no kernel oops. Nothing is written to the log. The magic sysreq key yields no response, although I have verified that it works before triggering the freeze. I've narrowed down the problem by calling "lsusb -v -s <device>". The system freezes on both devices of bus 3 (003:001 and 003:002). For all other devices, it prints the expected output and continues to work. When calling lsusb as a regular user, I get "Couldn't open device, some information will be missing", then the regular output, and the system keeps running. Therefore I assume that the problem is somewhere in the kernel, when the devices are accessed. This is a regression. It used to work in 14.10, and fails to work since 15.04. It also used to work in 14.04.2, and fails in 14.04.3. It fails with mainline builds 4.2.0-rc6-unstable, 4.2.0-rc2-unstable, 4.1.0-rc2-vivid. (yeah, I've been trying for a while :-) Incidentally, the shutdown sequence also freezes early on with the kernels that exhibit the problem; but I cannot be sure that the cause is the same. I decided to first chase the USB freeze, because it was easier to gather information about that. ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: linux-image-3.19.0-25-generic 3.19.0-25.26 ProcVersionSignature: Ubuntu 3.19.0-25.26-generic 3.19.8-ckt2 Uname: Linux 3.19.0-25-generic x86_64 ApportVersion: 2.17.2-0ubuntu1.2 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: rweber 1525 F.... pulseaudio CurrentDesktop: XFCE Date: Fri Aug 14 18:38:36 2015 HibernationDevice: RESUME=UUID=8a45266d-0232-428e-bb25-113d23caaf8a InstallationDate: Installed on 2015-06-28 (46 days ago) InstallationMedia: Xubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1) MachineType: Acer Aspire ES1-111M ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-25-generic root=UUID=b8872e03-7295-4cbd-ac86-06b9be2f112f ro quiet splash crashkernel=384M-:128M vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-3.19.0-25-generic N/A linux-backports-modules-3.19.0-25-generic N/A linux-firmware 1.143.3 SourcePackage: linux UpgradeStatus: Upgraded to vivid on 2015-07-05 (39 days ago) dmi.bios.date: 08/20/2014 dmi.bios.vendor: Insyde Corp. dmi.bios.version: V1.08 dmi.board.asset.tag: Type2 - Board Asset Tag dmi.board.name: R2 dmi.board.vendor: Acer dmi.board.version: Type2 - A01 Board Version dmi.chassis.type: 10 dmi.chassis.vendor: Chassis Manufacturer dmi.chassis.version: Chassis Version dmi.modalias: dmi:bvnInsydeCorp.:bvrV1.08:bd08/20/2014:svnAcer:pnAspireES1-111M:pvrV1.08:rvnAcer:rnR2:rvrType2-A01BoardVersion:cvnChassisManufacturer:ct10:cvrChassisVersion: dmi.product.name: Aspire ES1-111M dmi.product.version: V1.08 dmi.sys.vendor: Acer To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1485057/+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
