Today it seems I hit this bug. The last days I've been upgrading this machine with guix pull, and have been booting and reconfiguring fine until a few hours ago. Also, sorry about formatting. My config contained: (initrd (lambda (file-systems . rest) ;; Add a kernel module for RAID-0 (aka. "stripe") ;; and RAID-1 (aka. "mirror"). (apply base-initrd file-systems #:extra-modules '("raid0" "raid1") rest))) And I got an error from guix system reconfigure/build: : error: you may need these modules in the initrd for /dev/sdg2: uas usb_storage hint: Try adding them to the `initrd-modules' field of your `operating-system' declaration, (initrd-modules (append (list "uas" "usb_storage") The machine has the OS on a usb stick because all the internal SATA drives are RAID and I prefer to separate them. This machine has been configured like this for a long time. After following the recommendation (and finding the module in store is actually named usb-storage.ko) I end up with the following config snippet: (initrd-modules (append (list "uas" "usb-storage" "raid0" "raid1") %base-initrd-modules)) (initrd (lambda (file-systems . rest) ;; Add a kernel module for RAID-0 (aka. "stripe") ;; and RAID-1 (aka. "mirror"). (apply base-initrd file-systems #:extra-modules '("raid0" "raid1"); "uas" "usb-storage") rest))) This works if I use --skip-checks. But with checks it gives me the same error as above, changing the initrd-modules line to: (initrd-modules (append (list "uas" "usb_storage" "raid0" "raid1") Gives the following error: The following derivations will be built: /gnu/store/p5sash3cqywp5kmb9dwh8kbxy0rrdmc0-system.drv /gnu/store/g7pfwc7386x1bxf5pdv5nh1xz6ywxgxm-grub.cfg.drv /gnu/store/w57aw36wpc0388aa1frkj7h7qh8xac6z-parameters.drv /gnu/store/kh9v5z295kz4p79q3kancdv8d86n3cxr-linux-modules.drv /gnu/store/pbrj245mgv9zcy3shid348n8qdpv468v-init.drv /gnu/store/mvl7lb92g39d0qw08r2l2qiysvdf0sgs-raw-initrd.drv Backtrace: 6 (primitive-load "/gnu/store/hj17134gdpixdpif8nljwyh31k1?") In ice-9/eval.scm: 619:8 5 (_ #f) 626:19 4 (_ #) 293:34 3 (_ #) In srfi/srfi-1.scm: 592:29 2 (map1 _) 592:17 1 (map1 ("usb_storage" "raid0" "raid1" "ahci" "usb-sto?" ?)) In unknown file: 0 (scm-error misc-error #f "~A ~S ~S" ("module not fo?" ?) ?) ERROR: In procedure scm-error: module not found "usb_storage.ko" "/gnu/store/khxmq6p1470171537z8agikiqmi469jr-linux-libre-4.17/lib/modules" builder for `/gnu/store/kh9v5z295kz4p79q3kancdv8d86n3cxr-linux-modules.drv' failed with exit code 1 cannot build derivation `/gnu/store/pbrj245mgv9zcy3shid348n8qdpv468v-init.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/mvl7lb92g39d0qw08r2l2qiysvdf0sgs-raw-initrd.drv': 1 dependencies couldn't be built cannot build derivation `/gnu/store/g7pfwc7386x1bxf5pdv5nh1xz6ywxgxm-grub.cfg.drv': 1 dependencies couldn't be built guix system: error: build failed: build of `/gnu/store/g7pfwc7386x1bxf5pdv5nh1xz6ywxgxm-grub.cfg.drv' failed