Thanks @legolas558, I checked all cables and exchanged most of my USB equipment (hubs and cables). I tested in combinations which would reveal a faulty USB part. Inspired by your comment I opened the machine and checked the internal cable connections as well. They're all fine.
I `ddrescue` test case causes a kernel panic in 3.17-rc6, now, photo attached[1]. This occurs ~90 % of the time. I attach the log file of `ddrescue` 1.7.0 as well[2], maybe it can serve to produce a test file for you. It definitely works in the non-persistent live system based on 3.13.0-24-generic. --- [1] I'm currently stuck with `linux-crashtools`, please help me http://askubuntu.com/questions/529452/how-to-cause-a-test-crash-with-kdump for a text output of the panic stack. [2] Although the wiki states no compressed attachements, there's no way of figuring out how to attach a second file... ** Attachment added: "photo of kernel panic stack trace; ddrescue log file" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1371233/+attachment/4218432/+files/scsi_kernel_panic.tar.xz -- 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/1371233 Title: USB 3.0 connection is unreliable + xHCI xhci_drop_endpoint called with disabled ep Status in “linux” package in Ubuntu: Confirmed Bug description: based on https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1358871/comments/7 I tested with the HDD enclosure IcyBox IB-351 series with USB 3.0 connection with the same result (connection drops after 300 MB reading, error message "xHCI xhci_drop_endpoint called with disabled ep" occurs sometimes, other devices (e.g. Samsung HD103SI 1 TB HDD connected with 3.0 USB adapter to eSATA of enclosure) read hundreds of GB before failing, but definitely do before reading 1TB). Reading tested with `dd`, `gpart` and `btrfsck`. Also confirmed on Lenovo IdeaPad-Z500 after BIOS update to 71CN51WW(V1.21) (changelog didn't indicate any USB issues anyway). Also confirmed with 3.16.3 and 3.16.0-14 on Ubuntu 14.10-beta1 after updates. The issue seems to cause failure of ASIX AX179 gigabit ethernet chip as well, but is independent from the usage of the ethernet adapter. I'm without any clue and stuck with an unreliable USB and ethernet connection which basically means no I/O out of the machine!! ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.13.0-35-generic 3.13.0-35.62 ProcVersionSignature: Ubuntu 3.13.0-35.62-generic 3.13.11.6 Uname: Linux 3.13.0-35-generic x86_64 ApportVersion: 2.14.1-0ubuntu3.4 Architecture: amd64 AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-path', '/dev/snd/controlC0', '/dev/snd/hwC0D0', '/dev/snd/hwC0D3', '/dev/snd/pcmC0D0c', '/dev/snd/pcmC0D0p', '/dev/snd/pcmC0D3p', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: CurrentDesktop: Unity Date: Thu Sep 18 19:58:24 2014 EcryptfsInUse: Yes InstallationDate: Installed on 2014-09-10 (8 days ago) InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417) MachineType: LENOVO 20221 ProcEnviron: TERM=xterm PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=de_DE.UTF-8 SHELL=/bin/bash ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/@/boot/vmlinuz-3.13.0-35-generic.efi.signed root=UUID=5e999111-7efe-4818-b9e8-a950ad6d3296 ro rootflags=subvol=@ quiet splash nomdmonddf nomdmonisw vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-3.13.0-35-generic N/A linux-backports-modules-3.13.0-35-generic N/A linux-firmware 1.127.5 SourcePackage: linux StagingDrivers: rts5139 UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/12/2013 dmi.bios.vendor: LENOVO dmi.bios.version: 71CN51WW(V1.21) dmi.board.asset.tag: No Asset Tag dmi.board.name: INVALID dmi.board.vendor: LENOVO dmi.board.version: 31900003WIN8 STD MLT dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Lenovo IdeaPad Z500 Touch dmi.modalias: dmi:bvnLENOVO:bvr71CN51WW(V1.21):bd07/12/2013:svnLENOVO:pn20221:pvrLenovoIdeaPadZ500Touch:rvnLENOVO:rnINVALID:rvr31900003WIN8STDMLT:cvnLENOVO:ct10:cvrLenovoIdeaPadZ500Touch: dmi.product.name: 20221 dmi.product.version: Lenovo IdeaPad Z500 Touch dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1371233/+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
