Hi Ricardo, updated, hope the updated information is sufficient. ** Description changed:
+ [ Impact ] + + Systems using dracut to generate the initramfs on Ubuntu 26.04 fail to + resume from hibernation (S4) despite being correctly configured with a + valid swap device and resume= kernel parameter. + + Instead of restoring the previous system state, the machine performs a + normal cold boot after waking from hibernation, resulting in the loss of + the user's suspended session. + + This issue affects systems relying on ACPI S4 hibernation for power + management. In our testing, the problem is reproducible across Intel + Edge platforms spanning Atom- and Core-based variants, where hibernation + is an expected and supported. + + + [ Test Plan ] + + 1. Make sure system is supported the power state + user@localhost:~$ cat /sys/power/state + freeze mem disk + + 2. Configured swap partition and populated the resume kernel boot + parameter resume=/dev/<swap partition> and update the grub + + 3. Configured serial interface + + 4. In Serial interface execute s4 command sudo rtcwake -m disk -s 45 + + 5. Check whether system resume in login prompt or shell prompt + if land on shell prompt indicating s4 working + if land on login prompt indicating S4 is not working + + [ Where problems could occur ] + This change affects dracut initramfs generation by ensuring the resume path is included for hibernation support. + + If the change is incorrect, systems may still fail to resume from + hibernation even when resume= is configured correctly. The system may + continue to perform a normal cold boot instead of restoring the saved + hibernation image. + + A regression could also occur if the resume logic is included but does + not correctly handle the configured resume device. This may result in + failed resume attempts, delayed boot while the initramfs waits for the + resume device, or fallback to a normal boot. + + Systems without hibernation configured should continue to boot normally + and should not attempt to resume from a non-existent hibernation image. + + + [ Other Info ] + in u26.04 , system isn't resume the S4 hibernation despite kernel boot parameter configured the parameter: resume=/dev/<swap partition>. Issue is reported in upstream dracut https://github.com/dracut-ng/dracut/issues/1472 with temporary work around by including resume in dracut modules. /etc/dracut.conf.d/resume.conf add_dracutmodules+=" resume " # below line needs to be manually added right now install_items+=" /usr/lib/systemd/system/systemd-hibernate-resume.service " dracut -f --regenerate-all + + By including this WA, all S4 supported intel platforms is observed + working. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2158694 Title: dracut required resume module to perform S4 hibernation gracefully. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dracut/+bug/2158694/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
