notes:kernel_parameters
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Table of Contents
Information
- Kernel parameters that were useful at some point in time
Kernel Options
blk_mq
- I think the kernel at some point removed non-blk schedulers, so this isn't necessary
scsi_mod.use_blk_mq=y dm_mod.use_blk_mq=y
Corsair USB Quirks
usbcore.quirks=1b1c:1b38:gn,1b1c:1b3c:gn
Blacklist Watchdogs
iTCO_wdt
controls watchdog on some Intel platformssp5100_tco
controls watchdog on some AMD platformsnowatchdog
disables both soft and hard generic watchdogs- Apparently this reduces power usage slightly
modprobe.blacklist=iTCO_wdt,sp5100_tco nowatchdog
Microcode and Security Patches
- This disables all protection
mitigations=off
Modern Standby
- Use
S0
to suspend and wake quickly on supported systems - On a Dell XPS 13 9360, this used to be required, but the default
deep
option also works
mem_sleep_default=s2idle
dyntick-idle Disable
- KGPE-D16's Coreboot installation notes mention needing this for better power saving
nohz=on
intel_iommu
- Check
dmesg
for any DMAR-related errors
intel_iommu=on
i915
Safe
i915.enable_fbc=1
i915.fastboot=1
Hardware-specific
- GuC firmware loading/submission requires PAVP to be enabled in BIOS
- TODO: Figure out how to test PSR
i915.enable_psr=1
i915.enable_guc=3
radeon
radeon.deep_color=1
Backlight
- This prevents systemd from restoring previous backlight value on reboot
- This is necessary for Power Management
systemd.restore_state=0
DRM Debug
- This may make lower-end machines become very unresponsive; be prepared to have some safe way of rebooting
drm.debug=0xe
amdgpu
- Allows use of Overdrive options for overclocking
amdgpu.ppfeaturemask=0xffffffff
Verify
cat '/sys/module/amdgpu/parameters/ppfeaturemask' | grep '4294967295'
PCI
- May be useful for eGPU and Thunderbolt limits on Macs
pci=nocrs,pcie_bus_perf
Reboot
efi
is for UEFI systemspci
is for Legacy systems and Coreboot with SeaBIOS payload- There are other values possible should either of those not work
reboot=pci
reboot=efi
Custom Resolution
- This seems to only work on Wayland
- On Nightwane, using the refresh rate
59
in the below command works in Wayland, but not60
for p in /sys/class/drm/*/status; do con=${p%/status}; echo -n "${con#*/card?-}: "; cat $p; done
video=HDMI-A-1:3840x2160MR@59
/var/www/wiki/data/attic/notes/kernel_parameters.1575169340.txt.gz · Last modified: 2019/11/30 22:02 by Sean Rhone