Hi, The tests for DRBD encountered an issue with dm-delay when testing with a 6.8 series kernel. Specifically on Ubuntu 24.04 "Noble". Here is a minimal reproducer:
virter vm run --name dm-delay-test --id 10 --wait-ssh ubuntu-noble virter vm ssh dm-delay-test # truncate -s 100M /file # loop_dev=$(losetup -f --show /file) # echo "0 $(blockdev --getsz $loop_dev) delay $loop_dev 0 0" | dmsetup create delay-volume After a few minutes, the following is printed to the kernel log: [ 246.919123] INFO: task dm-delay-flush-:1256 blocked for more than 122 seconds. [ 246.922543] Not tainted 6.8.0-31-generic #31-Ubuntu [ 246.923753] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 246.924932] task:dm-delay-flush- state:D stack:0 pid:1256 tgid:1256 ppid:2 flags:0x00004000 [ 246.924940] Call Trace: [ 246.924950] <TASK> [ 246.924980] __schedule+0x27c/0x6b0 [ 246.925002] ? __pfx_flush_worker_fn+0x10/0x10 [dm_delay] [ 246.925011] schedule+0x33/0x110 [ 246.925016] schedule_preempt_disabled+0x15/0x30 [ 246.925035] kthread+0xb1/0x120 ... This bug appears to have been introduced in Linux v6.7. The following patch fixes the issue. Thanks Christian and Benjamin for the comments on v1! Changes from v1: - Use kthread_run() instead of wake_up_process() Joel Colledge (1): dm-delay: fix hung task introduced by kthread mode drivers/md/dm-delay.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) -- 2.34.1
