** Description changed: Copying a large file using cp on my Raspberry Pi 3B (not 3B+) from an externally-powered USB hard disk (Seagate Expansion 2TB) to an NFS- mounted filesystem across Ethernet causes the kernel of releases 19.10 and 20.04 to hang/freeze. This happens every time the copy is attempted, although the exact duration from the start of the copy to the hang varies from a few seconds to a couple of minutes. The kernel does not recover even after long waits (30mins+), and a power reset (pulling the plug) is required. (Although I admit I haven't tried yet simply disconnecting the USB cable - of the HDD during a hang.) + of the HDD during a hang. Update: I've now tried that - the system + doesn't recover after pulling the USB cable out.) Likewise, messages are erratic and I suspect are only symptoms, notably watchdog BUG soft lockup messages and RCU stall messages on different CPU cores for different processes/threads. There are no hardware messages that I've seen recorded in log files (or appearing on the console) matching the incidents. - Although I have had a swapfile configured on the SD card, the hang - continues to happen doing the cp after "swapoff -a". I've also tried + When a hang happen, network connectivity is lost - ssh sessions fail, + and the file copy stops (even when the cp is run on the console). Pings + to the system from other hosts on the same Ethernet LAN (and switch) + fail with destination host unreachable. + + Although I have had a swapfile configured on the SD card, the hangs + continue to happen doing the cp after "swapoff -a". I've also tried playing with taskset affinities and snappiness to no obvious effect - the hangs still keep happening. Copying from the external HDD to the SD card is successful, as is copying from the SD card to the NFS. Raspbian 4.19.0-8 (armmp-lpae) does not have this problem; it successfully copies the file from HDD to NFS across Ethernet without stalling. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: linux-image-5.4.0-1011-raspi 5.4.0-1011.11 ProcVersionSignature: Ubuntu 5.4.0-1011.11-raspi 5.4.34 Uname: Linux 5.4.0-1011-raspi aarch64 ApportVersion: 2.20.11-0ubuntu27 Architecture: arm64 CasperMD5CheckResult: skip Date: Fri Jun 5 07:37:44 2020 ProcEnviron: - TERM=xterm-256color - PATH=(custom, no user) - LANG=C.UTF-8 - SHELL=/bin/bash + TERM=xterm-256color + PATH=(custom, no user) + LANG=C.UTF-8 + SHELL=/bin/bash SourcePackage: linux-raspi UpgradeStatus: Upgraded to focal on 2020-05-21 (14 days ago)
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1882213 Title: cp file from external HDD to NFS on Pi 3B causes ubuntu 19.10 and 20.04 kernel to hang To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-raspi/+bug/1882213/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
