Test environment: Ubuntu 26.04 LTS on AWS c8a.metal-48xl (192 CPUs, 2 NUMA nodes)
Setups: 1. sudo tee /etc/default/grub.d/99-pulsar-repro.cfg >/dev/null <<'EOF' GRUB_CMDLINE_LINUX_DEFAULT="console=tty1 console=ttyS0 nvme_core.io_timeout=4294967295 isolcpus=nohz,18-95,108-178 nohz_full=18-95,108-178 rcu_nocbs=18-95,108-178 rcu_nocb_poll skew_tick=1 nosmt=force idle=poll numa_balancing=disable transparent_hugepage=never audit=0 nmi_watchdog=0 nowatchdog mce=ignore_ce tsc=reliable clocksource=tsc crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M panic=-1" EOF 2. sudo update-grub && sudo reboot 3. sudo apt-get install -y stress-ng linux-crashdump crash kdump-tools Results (all three kernels reproduce PID 1 entering D-state): - 7.0.0-1006-aws — DEFECT-BARRIER-STALL. PID 1 D-state ~60s, pgmigrate ~36 pages/s, self-recovered. - 7.0.0-1008-aws — EXPENSIVE-MIGRATION. PID 1 D-state ~16s, pgmigrate ~8K-41K pages/s, self-recovered. - 7.0.0-1011-aws — DEFECT-BARRIER-STALL. PID 1 D-state ~62s, pgmigrate ~36 pages/s, self-recovered. Attachment contains: - repro-baseline-v3.sh — reproduction script - test_log_7.0.0-1006-aws.zip — test log for kernel 7.0.0-1006-aws - test_log_7.0.0-1008-aws.zip — test log for kernel 7.0.0-1008-aws - test_log_7.0.0-1011-aws.zip — test log for kernel 7.0.0-1011-aws ** Attachment added: "test scripts & records" https://bugs.launchpad.net/ubuntu/+source/linux-aws/+bug/2165410/+attachment/5996304/+files/issue_reproduce.zip -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2165410 Title: Ubuntu LTS 26.04 linux-aws: systemd enters D state and blocks SSH during cpuset migration on nohz_full CPUs To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-aws/+bug/2165410/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
