From 6e0c5c33438e5e898bd075c33a45b3abf9d1b26b Mon Sep 17 00:00:00 2001 From: sommerfeld Date: Fri, 29 May 2026 11:18:15 +0100 Subject: feat(suspend): re-enable suspend on s2idle, drop diagnostic scaffolding MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Confirmed root cause: this hardware's S3 (deep) firmware path triggers a fatal wake-from-suspend hang only on linux-hardened. INIT_ON_FREE + slab hardening + tighter locking turn a latent driver race that stock linux gets away with into an unrecoverable panic so early the journal isn't even flushed. mem_sleep_default=s2idle bypasses the BIOS S3 path entirely (s0ix is a pure-kernel low-power state) and suspends/resumes reliably under hardened. This is a widespread Lenovo S3 firmware issue across post-2018 ThinkPads (see Ubuntu T560, X1C9/10/11 reports). Lenovo themselves moved newer firmwares to s2idle-only. Not a linux-hardened bug per se; just hardened being a strict enough kernel to make the bug fatal. Keep: * mem_sleep_default=s2idle in etc/kernel/cmdline-linux-hardened.tmpl (only the hardened UKI; stock linux keeps unchanged shared cmdline) Revert (all the diagnostic / speculative scaffolding from the last few commits): * MODULES=(intel_lpss_pci) → MODULES=() — Arch wiki touchpad fix was not the cause here * nmi_watchdog=panic softlockup_panic=1 panic=10 — only needed to auto-reboot during diagnosis * no_console_suspend — diagnostic-only * etc/systemd/logind.conf.d/20-no-suspend.conf — masking workaround * sleep-target masking block in run_onchange_after_deploy-etc.sh.tmpl, replaced with a one-shot cleanup that removes any leftover /dev/null symlinks from systems that ran the previous version * systemd-pstore.service from systemd-units/system.txt — added only to catch the diagnostic panic * diagnose-suspend.sh helper (and its .gitignore/.chezmoiignore entries) * sway suspend → lock-session keybind workaround * power-menu.sh Suspend entry restoration * KEYBINDS.md docs --- etc/kernel/cmdline-linux-hardened.tmpl | 2 +- etc/mkinitcpio.conf | 2 +- etc/mkinitcpio.d/linux-hardened.preset | 10 ++++++---- etc/systemd/logind.conf.d/20-no-suspend.conf | 17 ----------------- 4 files changed, 8 insertions(+), 23 deletions(-) delete mode 100644 etc/systemd/logind.conf.d/20-no-suspend.conf (limited to 'etc') diff --git a/etc/kernel/cmdline-linux-hardened.tmpl b/etc/kernel/cmdline-linux-hardened.tmpl index 45dff5e..be99a9c 100644 --- a/etc/kernel/cmdline-linux-hardened.tmpl +++ b/etc/kernel/cmdline-linux-hardened.tmpl @@ -1 +1 @@ -rd.luks.name={{ output "lsblk" "-dno" "UUID" (printf "/dev/%s" .luksRootPartition) | trim }}=root root=/dev/mapper/root rw mem_sleep_default=s2idle no_console_suspend nmi_watchdog=panic softlockup_panic=1 panic=10 +rd.luks.name={{ output "lsblk" "-dno" "UUID" (printf "/dev/%s" .luksRootPartition) | trim }}=root root=/dev/mapper/root rw quiet mem_sleep_default=s2idle diff --git a/etc/mkinitcpio.conf b/etc/mkinitcpio.conf index d8ae3ff..fab5fa1 100644 --- a/etc/mkinitcpio.conf +++ b/etc/mkinitcpio.conf @@ -4,7 +4,7 @@ # run. Advanced users may wish to specify all system modules # in this array. For instance: # MODULES=(usbhid xhci_hcd) -MODULES=(intel_lpss_pci) +MODULES=() # BINARIES # This setting includes any additional binaries a given user may diff --git a/etc/mkinitcpio.d/linux-hardened.preset b/etc/mkinitcpio.d/linux-hardened.preset index 90be917..fcb94a5 100644 --- a/etc/mkinitcpio.d/linux-hardened.preset +++ b/etc/mkinitcpio.d/linux-hardened.preset @@ -1,9 +1,11 @@ # mkinitcpio preset for the 'linux-hardened' kernel. Produces a UKI at # /boot/EFI/Linux/arch-linux-hardened.efi alongside the stock linux UKI. -# Uses its own cmdline file (etc/kernel/cmdline-linux-hardened.tmpl) -# carrying hang-detection knobs while we validate the suspend/resume -# fix on this hardware. The stock linux UKI keeps the minimal -# etc/kernel/cmdline.tmpl. Register the EFI entry once with efibootmgr: +# Uses its own cmdline file (etc/kernel/cmdline-linux-hardened.tmpl) to +# force `mem_sleep_default=s2idle`: this hardware's S3 firmware path +# wakes reliably on stock linux but hard-hangs the hardened kernel +# (INIT_ON_FREE + slab hardening turn a latent driver race fatal). +# Stock linux keeps the minimal etc/kernel/cmdline.tmpl. Register the +# EFI entry once with efibootmgr: # # sudo efibootmgr --create --disk /dev/nvme0n1 --part 1 \ # --label 'Arch Hardened' --loader '\EFI\Linux\arch-linux-hardened.efi' diff --git a/etc/systemd/logind.conf.d/20-no-suspend.conf b/etc/systemd/logind.conf.d/20-no-suspend.conf deleted file mode 100644 index 1b58aa4..0000000 --- a/etc/systemd/logind.conf.d/20-no-suspend.conf +++ /dev/null @@ -1,17 +0,0 @@ -[Login] -# Suspend is disabled while the linux-hardened wake-from-S3 hang is -# unresolved (NVMe / i915 / iwlwifi driver UAF surfaced by INIT_ON_FREE -# + slab hardening). Lid close, suspend/hibernate keys, and idle action -# all fall back to session lock instead of suspend. The sleep/suspend/ -# hibernate targets are also masked at the unit level via the etc/ -# deploy script as belt-and-braces against `systemctl suspend` from -# anywhere. Screen-off (DPMS) and swaylock continue to be driven by -# swayidle and are unaffected. -HandleLidSwitch=lock -HandleLidSwitchExternalPower=lock -HandleLidSwitchDocked=ignore -HandleSuspendKey=lock -HandleSuspendKeyLongPress=ignore -HandleHibernateKey=lock -HandleHibernateKeyLongPress=ignore -IdleAction=ignore -- cgit v1.3.1