Public bug reported: The issue is that deleting a LUN on the target will hang until IO is attempted to this LUN from the initiator.
This issue was introduced when linux-image-generic-hwe-18.04 switched from the 5.0 to the 5.3 kernel. Source package is "linux-meta-hwe". OS is Ubuntu 18.04.4 LTS. We can see a hung task message in dmesg: [ 1330.438613] INFO: task iscsicmd:24572 blocked for more than 120 seconds. [ 1330.439554] Tainted: P OE 5.3.0-26-generic #28~18.04.1-Ubuntu [ 1330.440594] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1330.441666] iscsicmd D 0 24572 8910 0x00000080 [ 1330.441668] Call Trace: [ 1330.441674] __schedule+0x2a8/0x670 [ 1330.441676] schedule+0x33/0xa0 [ 1330.441678] schedule_timeout+0x1d3/0x2f0 [ 1330.441682] ? __kfifo_to_user_r+0xb0/0xb0 [ 1330.441684] wait_for_completion+0xba/0x140 [ 1330.441688] ? wake_up_q+0x80/0x80 [ 1330.441704] transport_clear_lun_ref+0x27/0x30 [target_core_mod] [ 1330.441711] core_tpg_remove_lun+0x35/0x100 [target_core_mod] [ 1330.441716] core_dev_del_lun+0x26/0x70 [target_core_mod] [ 1330.441721] target_fabric_port_unlink+0x4a/0x50 [target_core_mod] [ 1330.441724] configfs_unlink+0xea/0x1b0 [ 1330.441727] vfs_unlink+0x111/0x200 [ 1330.441729] do_unlinkat+0x2ad/0x320 [ 1330.441731] __x64_sys_unlink+0x23/0x30 [ 1330.441734] do_syscall_64+0x5a/0x130 [ 1330.441736] entry_SYSCALL_64_after_hwframe+0x44/0xa9 (iscsicmd is a cli tool I created that is similar to targetcli) You can find more details about this bug and the reproducer on this linux kernel discussion thread: https://lkml.org/lkml/2020/2/7/585 A patch has been already submitted by an iSCSI-target developer, although not yet integrated. (https://marc.info/?l=target- devel&m=158134893208641&w=2) Would it be possible to get this patch integrated into the linux-image- generic-hwe-18.04 package, and if yes, then what would be the required next steps? ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: linux-image-generic-hwe-18.04 5.3.0.28.96 ProcVersionSignature: Ubuntu 5.3.0-28.30~18.04.1-generic 5.3.13 Uname: Linux 5.3.0-28-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.9 Architecture: amd64 Date: Mon Feb 10 18:41:12 2020 ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=C.UTF-8 SHELL=/bin/bash SourcePackage: linux-meta-hwe UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: linux-meta-hwe (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug bionic uec-images -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1862682 Title: iSCSI-target: Deleting a LUN hangs in the kernel To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-meta-hwe/+bug/1862682/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
