77 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			Nix
		
	
	
	
	
	
			
		
		
	
	
			77 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			Nix
		
	
	
	
	
	
| { config, lib, pkgs, ... }:
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| 
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| with lib;
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| 
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| let
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|   crashdump = config.boot.crashDump;
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| 
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|   kernelParams = concatStringsSep " " crashdump.kernelParams;
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| 
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| in
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| ###### interface
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| {
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|   options = {
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|     boot = {
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|       crashDump = {
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|         enable = mkOption {
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|           type = types.bool;
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|           default = false;
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|           description = ''
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|             If enabled, NixOS will set up a kernel that will
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|             boot on crash, and leave the user in systemd rescue
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|             to be able to save the crashed kernel dump at
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|             /proc/vmcore.
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|             It also activates the NMI watchdog.
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|           '';
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|         };
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|         reservedMemory = mkOption {
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|           default = "128M";
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|           type = types.str;
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|           description = ''
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|             The amount of memory reserved for the crashdump kernel.
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|             If you choose a too high value, dmesg will mention
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|             "crashkernel reservation failed".
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|           '';
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|         };
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|         kernelParams = mkOption {
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|           type = types.listOf types.str;
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|           default = [ "1" "boot.shell_on_fail" ];
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|           description = ''
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|             Parameters that will be passed to the kernel kexec-ed on crash.
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|           '';
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|         };
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|       };
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|     };
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|   };
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| 
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| ###### implementation
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| 
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|   config = mkIf crashdump.enable {
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|     boot = {
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|       postBootCommands = ''
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|         echo "loading crashdump kernel...";
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|         ${pkgs.kexectools}/sbin/kexec -p /run/current-system/kernel \
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|         --initrd=/run/current-system/initrd \
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|         --reset-vga --console-vga \
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|         --command-line="systemConfig=$(readlink -f /run/current-system) init=$(readlink -f /run/current-system/init) irqpoll maxcpus=1 reset_devices ${kernelParams}"
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|       '';
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|       kernelParams = [
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|        "crashkernel=${crashdump.reservedMemory}"
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|        "nmi_watchdog=panic"
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|        "softlockup_panic=1"
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|       ];
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|       kernelPatches = [ {
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|         name = "crashdump-config";
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|         patch = null;
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|         extraConfig = ''
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|                 CRASH_DUMP y
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|                 DEBUG_INFO y
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|                 PROC_VMCORE y
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|                 LOCKUP_DETECTOR y
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|                 HARDLOCKUP_DETECTOR y
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|               '';
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|         } ];
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|     };
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|   };
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| }
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