[Bug 2140442] Re: cp: cannot stat '/boot/firmware/current/cmdline.txt': No such file or directory
Dave Jones
2140442 at bugs.launchpad.net
Fri Feb 6 10:47:56 UTC 2026
Excellent, glad to hear it's booted successfully. I'm going to rename
this bug to something to ensure a slightly saner fallback in the case
cmdline.txt doesn't exist.
** Summary changed:
- cp: cannot stat '/boot/firmware/current/cmdline.txt': No such file or directory
+ Use /proc/cmdline if current/cmdline.txt does not exist
** Description changed:
+ In the case that /cmdline.txt does not exist during migration, or in the
+ case that /current/cmdline.txt does not exist during a regular flash-
+ kernel run, construct one from the content of /proc/cmdline.
+
+ Some filtering will be necessary -- not sure yet whether exclusion of
+ things known to be generated by the bootloader, or filtering to include
+ only those things we typically include is a better idea...
+
+ The exclusion idea probably won't keep up with future changes to the
+ bootloader, but this is an emergency fallback and it may not matter that
+ much if it's "good enough". The filtering idea has to incorporate
+ everything that's critical for boot -- easy enough for local SD / SSD /
+ NVMe, but what about netboot? (nfsroot, nbdroot, etc. etc.)
+
+ I'm favouring filtering, but need to do some more research on everything
+ critical in netboot.
+
+ [ Original Description ]
+
This interrupted a release upgrade from plucky to questing on my pi4.
After dropping to a shell, "apt -f install" yields the same error, as
does just calling "flash-kernel":
root at pi4:~# apt -f install
The following packages were automatically installed and are no longer required:
- g++-14 libboost-iostreams1.83.0 libclang-cpp18 libllvm19 libxml2 linux-raspi-tools-6.14.0-1018
- g++-14-aarch64-linux-gnu libboost-locale1.83.0 libclang1-19 libreiserfscore0t64 linux-headers-6.14.0-1018-raspi linux-tools-6.14.0-1018-raspi
- gir1.2-nautilus-4.0 libboost-program-options1.83.0 libfuse3-3 libsframe1 linux-image-6.14.0-1018-raspi python3-packaging-whl
- libboost-context1.83.0 libboost-thread1.83.0 libgnutls-openssl27t64 libsigsegv2 linux-modules-6.14.0-1018-raspi python3-wheel-whl
- libboost-filesystem1.83.0 libboost-url1.83.0 libllvm18 libstdc++-14-dev linux-raspi-headers-6.14.0-1018
+ g++-14 libboost-iostreams1.83.0 libclang-cpp18 libllvm19 libxml2 linux-raspi-tools-6.14.0-1018
+ g++-14-aarch64-linux-gnu libboost-locale1.83.0 libclang1-19 libreiserfscore0t64 linux-headers-6.14.0-1018-raspi linux-tools-6.14.0-1018-raspi
+ gir1.2-nautilus-4.0 libboost-program-options1.83.0 libfuse3-3 libsframe1 linux-image-6.14.0-1018-raspi python3-packaging-whl
+ libboost-context1.83.0 libboost-thread1.83.0 libgnutls-openssl27t64 libsigsegv2 linux-modules-6.14.0-1018-raspi python3-wheel-whl
+ libboost-filesystem1.83.0 libboost-url1.83.0 libllvm18 libstdc++-14-dev linux-raspi-headers-6.14.0-1018
Use 'apt autoremove' to remove them.
Summary:
- Upgrading: 0, Installing: 0, Removing: 0, Not Upgrading: 0
- 1 not fully installed or removed.
- Space needed: 0 B / 47.6 GB available
+ Upgrading: 0, Installing: 0, Removing: 0, Not Upgrading: 0
+ 1 not fully installed or removed.
+ Space needed: 0 B / 47.6 GB available
Setting up initramfs-tools (0.150ubuntu3.1) ...
update-initramfs: deferring update (trigger activated)
Processing triggers for flash-kernel (3.109ubuntu6.2) ...
Using DTB: bcm2711-rpi-4-b.dtb
Installing /lib/firmware/6.17.0-1007-raspi/device-tree/broadcom/bcm2711-rpi-4-b.dtb into /boot/dtbs/6.17.0-1007-raspi/./bcm2711-rpi-4-b.dtb
Taking backup of bcm2711-rpi-4-b.dtb.
Installing new bcm2711-rpi-4-b.dtb.
flash-kernel: installing version 6.17.0-1007-raspi
Copying kernel assets to /boot/firmware/new/
cp: cannot stat '/boot/firmware/current/cmdline.txt': No such file or directory
dpkg: error processing package flash-kernel (--configure):
- installed flash-kernel package post-installation script subprocess returned error exit status 1
+ installed flash-kernel package post-installation script subprocess returned error exit status 1
Processing triggers for initramfs-tools (0.150ubuntu3.1) ...
update-initramfs: Generating /boot/initrd.img-6.17.0-1007-raspi
Using DTB: bcm2711-rpi-4-b.dtb
Installing /lib/firmware/6.17.0-1007-raspi/device-tree/broadcom/bcm2711-rpi-4-b.dtb into /boot/dtbs/6.17.0-1007-raspi/./bcm2711-rpi-4-b.dtb
Taking backup of bcm2711-rpi-4-b.dtb.
Installing new bcm2711-rpi-4-b.dtb.
flash-kernel: installing version 6.17.0-1007-raspi
Copying kernel assets to /boot/firmware/new/
cp: cannot stat '/boot/firmware/current/cmdline.txt': No such file or directory
run-parts: /etc/initramfs/post-update.d//flash-kernel exited with return code 1
dpkg: error processing package initramfs-tools (--configure):
- installed initramfs-tools package post-installation script subprocess returned error exit status 1
+ installed initramfs-tools package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
- flash-kernel
- initramfs-tools
+ flash-kernel
+ initramfs-tools
Error: Sub-process /usr/bin/dpkg returned an error code (1)
-
- If this matters, here is /boot/firmware/current and a find showing that no cmdline.txt file exists anywhere under /boot:
+ If this matters, here is /boot/firmware/current and a find showing that
+ no cmdline.txt file exists anywhere under /boot:
root at pi4:~# find /boot -name cmdline.txt
root at pi4:~# l /boot/firmware/current/
total 98M
drwxr-xr-x 3 root root 4.5K Feb 4 17:19 .
drwxr-xr-x 4 root root 11K Jan 1 1970 ..
-rwxr-xr-x 1 root root 32K Feb 4 17:18 bcm2710-rpi-2-b.dtb
-rwxr-xr-x 1 root root 35K Feb 4 17:18 bcm2710-rpi-3-b-plus.dtb
-rwxr-xr-x 1 root root 35K Feb 4 17:18 bcm2710-rpi-3-b.dtb
-rwxr-xr-x 1 root root 32K Feb 4 17:18 bcm2710-rpi-cm3.dtb
-rwxr-xr-x 1 root root 34K Feb 4 17:18 bcm2710-rpi-zero-2-w.dtb
-rwxr-xr-x 1 root root 34K Feb 4 17:18 bcm2710-rpi-zero-2.dtb
-rwxr-xr-x 1 root root 55K Feb 4 17:18 bcm2711-rpi-4-b.dtb
-rwxr-xr-x 1 root root 55K Feb 4 17:18 bcm2711-rpi-400.dtb
-rwxr-xr-x 1 root root 38K Feb 4 17:18 bcm2711-rpi-cm4-io.dtb
-rwxr-xr-x 1 root root 56K Feb 4 17:18 bcm2711-rpi-cm4.dtb
-rwxr-xr-x 1 root root 53K Feb 4 17:18 bcm2711-rpi-cm4s.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-d-rpi-5-b.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-rpi-5-b.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-rpi-500.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-rpi-cm5-cm4io.dtb
-rwxr-xr-x 1 root root 78K Feb 4 17:18 bcm2712-rpi-cm5-cm5io.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-rpi-cm5l-cm4io.dtb
-rwxr-xr-x 1 root root 78K Feb 4 17:18 bcm2712-rpi-cm5l-cm5io.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712d0-rpi-5-b.dtb
-rwxr-xr-x 1 root root 21K Feb 4 17:18 bcm2837-rpi-3-a-plus.dtb
-rwxr-xr-x 1 root root 21K Feb 4 17:18 bcm2837-rpi-3-b-plus.dtb
-rwxr-xr-x 1 root root 21K Feb 4 17:18 bcm2837-rpi-3-b.dtb
-rwxr-xr-x 1 root root 20K Feb 4 17:18 bcm2837-rpi-cm3-io3.dtb
-rwxr-xr-x 1 root root 21K Feb 4 17:18 bcm2837-rpi-zero-2-w.dtb
-rwxr-xr-x 1 root root 4.2K Feb 4 17:18 blaize-blzp1600-cb2.dtb
-rwxr-xr-x 1 root root 52K Feb 4 17:18 bootcode.bin
-rwxr-xr-x 1 root root 2.7K Feb 4 17:18 en7581-evb.dtb
-rwxr-xr-x 1 root root 7.2K Feb 4 17:18 fixup.dat
-rwxr-xr-x 1 root root 5.4K Feb 4 17:18 fixup4.dat
-rwxr-xr-x 1 root root 3.2K Feb 4 17:18 fixup4cd.dat
-rwxr-xr-x 1 root root 8.3K Feb 4 17:18 fixup4db.dat
-rwxr-xr-x 1 root root 8.3K Feb 4 17:18 fixup4x.dat
-rwxr-xr-x 1 root root 3.2K Feb 4 17:18 fixup_cd.dat
-rwxr-xr-x 1 root root 11K Feb 4 17:18 fixup_db.dat
-rwxr-xr-x 1 root root 11K Feb 4 17:18 fixup_x.dat
-rwxr-xr-x 1 root root 2.3K Feb 4 17:18 hat_map.dtb
-rwxr-xr-x 1 root root 63M Feb 4 17:18 initrd.img
-rwxr-xr-x 1 root root 1.5K Feb 4 17:18 overlay_map.dtb
drwxr-xr-x 2 root root 31K Feb 4 17:19 overlays
-rwxr-xr-x 1 root root 2.9M Feb 4 17:18 start.elf
-rwxr-xr-x 1 root root 2.2M Feb 4 17:18 start4.elf
-rwxr-xr-x 1 root root 790K Feb 4 17:18 start4cd.elf
-rwxr-xr-x 1 root root 3.6M Feb 4 17:18 start4db.elf
-rwxr-xr-x 1 root root 2.9M Feb 4 17:18 start4x.elf
-rwxr-xr-x 1 root root 790K Feb 4 17:18 start_cd.elf
-rwxr-xr-x 1 root root 4.7M Feb 4 17:18 start_db.elf
-rwxr-xr-x 1 root root 3.6M Feb 4 17:18 start_x.elf
-rwxr-xr-x 1 root root 5 Feb 4 17:19 state
-rwxr-xr-x 1 root root 13M Feb 4 17:18 vmlinuz
ProblemType: Bug
DistroRelease: Ubuntu 25.10
Package: flash-kernel 3.109ubuntu6.2
ProcVersionSignature: Ubuntu 6.14.0-1019.19-raspi 6.14.11
Uname: Linux 6.14.0-1019-raspi aarch64
NonfreeKernelModules: zfs
ApportVersion: 2.33.1-0ubuntu3
Architecture: arm64
CasperMD5CheckResult: unknown
CloudBuildName: server
CloudSerial:
-
+
Date: Wed Feb 4 18:58:32 2026
ProcEnviron:
- LANG=C.UTF-8
- PATH=(custom, no user)
- SHELL=/bin/bash
- TERM=screen-256color
- XDG_RUNTIME_DIR=<set>
+ LANG=C.UTF-8
+ PATH=(custom, no user)
+ SHELL=/bin/bash
+ TERM=screen-256color
+ XDG_RUNTIME_DIR=<set>
RebootRequiredPkgs: Error: path contained symlinks.
SourcePackage: flash-kernel
UpgradeStatus: Upgraded to questing on 2026-02-04 (0 days ago)
** Changed in: flash-kernel (Ubuntu)
Milestone: None => ubuntu-26.04
** Changed in: flash-kernel (Ubuntu)
Assignee: (unassigned) => Dave Jones (waveform)
** Changed in: flash-kernel (Ubuntu)
Status: New => Triaged
** Changed in: flash-kernel (Ubuntu)
Importance: Undecided => High
--
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Foundations Bugs, which is subscribed to flash-kernel in Ubuntu.
https://bugs.launchpad.net/bugs/2140442
Title:
Use /proc/cmdline if current/cmdline.txt does not exist
Status in flash-kernel package in Ubuntu:
Triaged
Bug description:
In the case that /cmdline.txt does not exist during migration, or in
the case that /current/cmdline.txt does not exist during a regular
flash-kernel run, construct one from the content of /proc/cmdline.
Some filtering will be necessary -- not sure yet whether exclusion of
things known to be generated by the bootloader, or filtering to
include only those things we typically include is a better idea...
The exclusion idea probably won't keep up with future changes to the
bootloader, but this is an emergency fallback and it may not matter
that much if it's "good enough". The filtering idea has to incorporate
everything that's critical for boot -- easy enough for local SD / SSD
/ NVMe, but what about netboot? (nfsroot, nbdroot, etc. etc.)
I'm favouring filtering, but need to do some more research on
everything critical in netboot.
[ Original Description ]
This interrupted a release upgrade from plucky to questing on my pi4.
After dropping to a shell, "apt -f install" yields the same error, as
does just calling "flash-kernel":
root at pi4:~# apt -f install
The following packages were automatically installed and are no longer required:
g++-14 libboost-iostreams1.83.0 libclang-cpp18 libllvm19 libxml2 linux-raspi-tools-6.14.0-1018
g++-14-aarch64-linux-gnu libboost-locale1.83.0 libclang1-19 libreiserfscore0t64 linux-headers-6.14.0-1018-raspi linux-tools-6.14.0-1018-raspi
gir1.2-nautilus-4.0 libboost-program-options1.83.0 libfuse3-3 libsframe1 linux-image-6.14.0-1018-raspi python3-packaging-whl
libboost-context1.83.0 libboost-thread1.83.0 libgnutls-openssl27t64 libsigsegv2 linux-modules-6.14.0-1018-raspi python3-wheel-whl
libboost-filesystem1.83.0 libboost-url1.83.0 libllvm18 libstdc++-14-dev linux-raspi-headers-6.14.0-1018
Use 'apt autoremove' to remove them.
Summary:
Upgrading: 0, Installing: 0, Removing: 0, Not Upgrading: 0
1 not fully installed or removed.
Space needed: 0 B / 47.6 GB available
Setting up initramfs-tools (0.150ubuntu3.1) ...
update-initramfs: deferring update (trigger activated)
Processing triggers for flash-kernel (3.109ubuntu6.2) ...
Using DTB: bcm2711-rpi-4-b.dtb
Installing /lib/firmware/6.17.0-1007-raspi/device-tree/broadcom/bcm2711-rpi-4-b.dtb into /boot/dtbs/6.17.0-1007-raspi/./bcm2711-rpi-4-b.dtb
Taking backup of bcm2711-rpi-4-b.dtb.
Installing new bcm2711-rpi-4-b.dtb.
flash-kernel: installing version 6.17.0-1007-raspi
Copying kernel assets to /boot/firmware/new/
cp: cannot stat '/boot/firmware/current/cmdline.txt': No such file or directory
dpkg: error processing package flash-kernel (--configure):
installed flash-kernel package post-installation script subprocess returned error exit status 1
Processing triggers for initramfs-tools (0.150ubuntu3.1) ...
update-initramfs: Generating /boot/initrd.img-6.17.0-1007-raspi
Using DTB: bcm2711-rpi-4-b.dtb
Installing /lib/firmware/6.17.0-1007-raspi/device-tree/broadcom/bcm2711-rpi-4-b.dtb into /boot/dtbs/6.17.0-1007-raspi/./bcm2711-rpi-4-b.dtb
Taking backup of bcm2711-rpi-4-b.dtb.
Installing new bcm2711-rpi-4-b.dtb.
flash-kernel: installing version 6.17.0-1007-raspi
Copying kernel assets to /boot/firmware/new/
cp: cannot stat '/boot/firmware/current/cmdline.txt': No such file or directory
run-parts: /etc/initramfs/post-update.d//flash-kernel exited with return code 1
dpkg: error processing package initramfs-tools (--configure):
installed initramfs-tools package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
flash-kernel
initramfs-tools
Error: Sub-process /usr/bin/dpkg returned an error code (1)
If this matters, here is /boot/firmware/current and a find showing
that no cmdline.txt file exists anywhere under /boot:
root at pi4:~# find /boot -name cmdline.txt
root at pi4:~# l /boot/firmware/current/
total 98M
drwxr-xr-x 3 root root 4.5K Feb 4 17:19 .
drwxr-xr-x 4 root root 11K Jan 1 1970 ..
-rwxr-xr-x 1 root root 32K Feb 4 17:18 bcm2710-rpi-2-b.dtb
-rwxr-xr-x 1 root root 35K Feb 4 17:18 bcm2710-rpi-3-b-plus.dtb
-rwxr-xr-x 1 root root 35K Feb 4 17:18 bcm2710-rpi-3-b.dtb
-rwxr-xr-x 1 root root 32K Feb 4 17:18 bcm2710-rpi-cm3.dtb
-rwxr-xr-x 1 root root 34K Feb 4 17:18 bcm2710-rpi-zero-2-w.dtb
-rwxr-xr-x 1 root root 34K Feb 4 17:18 bcm2710-rpi-zero-2.dtb
-rwxr-xr-x 1 root root 55K Feb 4 17:18 bcm2711-rpi-4-b.dtb
-rwxr-xr-x 1 root root 55K Feb 4 17:18 bcm2711-rpi-400.dtb
-rwxr-xr-x 1 root root 38K Feb 4 17:18 bcm2711-rpi-cm4-io.dtb
-rwxr-xr-x 1 root root 56K Feb 4 17:18 bcm2711-rpi-cm4.dtb
-rwxr-xr-x 1 root root 53K Feb 4 17:18 bcm2711-rpi-cm4s.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-d-rpi-5-b.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-rpi-5-b.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-rpi-500.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-rpi-cm5-cm4io.dtb
-rwxr-xr-x 1 root root 78K Feb 4 17:18 bcm2712-rpi-cm5-cm5io.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712-rpi-cm5l-cm4io.dtb
-rwxr-xr-x 1 root root 78K Feb 4 17:18 bcm2712-rpi-cm5l-cm5io.dtb
-rwxr-xr-x 1 root root 77K Feb 4 17:18 bcm2712d0-rpi-5-b.dtb
-rwxr-xr-x 1 root root 21K Feb 4 17:18 bcm2837-rpi-3-a-plus.dtb
-rwxr-xr-x 1 root root 21K Feb 4 17:18 bcm2837-rpi-3-b-plus.dtb
-rwxr-xr-x 1 root root 21K Feb 4 17:18 bcm2837-rpi-3-b.dtb
-rwxr-xr-x 1 root root 20K Feb 4 17:18 bcm2837-rpi-cm3-io3.dtb
-rwxr-xr-x 1 root root 21K Feb 4 17:18 bcm2837-rpi-zero-2-w.dtb
-rwxr-xr-x 1 root root 4.2K Feb 4 17:18 blaize-blzp1600-cb2.dtb
-rwxr-xr-x 1 root root 52K Feb 4 17:18 bootcode.bin
-rwxr-xr-x 1 root root 2.7K Feb 4 17:18 en7581-evb.dtb
-rwxr-xr-x 1 root root 7.2K Feb 4 17:18 fixup.dat
-rwxr-xr-x 1 root root 5.4K Feb 4 17:18 fixup4.dat
-rwxr-xr-x 1 root root 3.2K Feb 4 17:18 fixup4cd.dat
-rwxr-xr-x 1 root root 8.3K Feb 4 17:18 fixup4db.dat
-rwxr-xr-x 1 root root 8.3K Feb 4 17:18 fixup4x.dat
-rwxr-xr-x 1 root root 3.2K Feb 4 17:18 fixup_cd.dat
-rwxr-xr-x 1 root root 11K Feb 4 17:18 fixup_db.dat
-rwxr-xr-x 1 root root 11K Feb 4 17:18 fixup_x.dat
-rwxr-xr-x 1 root root 2.3K Feb 4 17:18 hat_map.dtb
-rwxr-xr-x 1 root root 63M Feb 4 17:18 initrd.img
-rwxr-xr-x 1 root root 1.5K Feb 4 17:18 overlay_map.dtb
drwxr-xr-x 2 root root 31K Feb 4 17:19 overlays
-rwxr-xr-x 1 root root 2.9M Feb 4 17:18 start.elf
-rwxr-xr-x 1 root root 2.2M Feb 4 17:18 start4.elf
-rwxr-xr-x 1 root root 790K Feb 4 17:18 start4cd.elf
-rwxr-xr-x 1 root root 3.6M Feb 4 17:18 start4db.elf
-rwxr-xr-x 1 root root 2.9M Feb 4 17:18 start4x.elf
-rwxr-xr-x 1 root root 790K Feb 4 17:18 start_cd.elf
-rwxr-xr-x 1 root root 4.7M Feb 4 17:18 start_db.elf
-rwxr-xr-x 1 root root 3.6M Feb 4 17:18 start_x.elf
-rwxr-xr-x 1 root root 5 Feb 4 17:19 state
-rwxr-xr-x 1 root root 13M Feb 4 17:18 vmlinuz
ProblemType: Bug
DistroRelease: Ubuntu 25.10
Package: flash-kernel 3.109ubuntu6.2
ProcVersionSignature: Ubuntu 6.14.0-1019.19-raspi 6.14.11
Uname: Linux 6.14.0-1019-raspi aarch64
NonfreeKernelModules: zfs
ApportVersion: 2.33.1-0ubuntu3
Architecture: arm64
CasperMD5CheckResult: unknown
CloudBuildName: server
CloudSerial:
Date: Wed Feb 4 18:58:32 2026
ProcEnviron:
LANG=C.UTF-8
PATH=(custom, no user)
SHELL=/bin/bash
TERM=screen-256color
XDG_RUNTIME_DIR=<set>
RebootRequiredPkgs: Error: path contained symlinks.
SourcePackage: flash-kernel
UpgradeStatus: Upgraded to questing on 2026-02-04 (0 days ago)
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