X1 L850-GL Fedora Recovery v1.0

Working recovery bundle for a ThinkPad X1 Carbon with Fibocom L850-GL / Intel XMM7360 on Fedora.

This bundle is intentionally conservative: preserve basic function over speed.

What this contains

Manual Hammer:

/usr/local/sbin/l850gl-manual-rescue.sh

Boot recovery:

/usr/local/sbin/l850gl-boot-recovery.sh
/etc/systemd/system/l850gl-boot-rescue.service

Shared config:

/etc/default/l850gl-recovery

The boot service calls only the boot recovery script. It does not call the manual Hammer.

External source trees required

This package does not vendor the external source trees. It expects them to exist locally:

~/src/acpi_call
~/src/xmm7360-usb-modeswitch

By default, install.sh detects the sudoing user and writes the paths to:

/etc/default/l850gl-recovery

For another layout, set overrides before installing:

sudo L850GL_USER="$USER" \
  L850GL_HOME="$HOME" \
  XMM2USB="$HOME/src/xmm7360-usb-modeswitch/xmm2usb" \
  ACPI_SRC="$HOME/src/acpi_call" \
  ./install.sh

Known-good result

After boot:

cdc-wdm0  gsm  connected  voxi
USB 2cb7:0007 Fibocom L850-GL
ModemManager plugin: fibocom
primary port: cdc-wdm0
l850gl-boot-rescue.service: status=0/SUCCESS

Known-good path

Boot state:

USB 2cb7:0007 absent
PCI 8086:7360 present
No ModemManager modem

Recovery path:

modprobe acpi_call
/proc/acpi/call present
xmm2usb once
USB 2cb7:0007 appears
/dev/cdc-wdm0 appears
udev marks MBIM
ModemManager adopts Fibocom L850-GL using cdc-wdm0
NetworkManager brings up voxi

Prerequisite: FCC lock cleared

This enable repo assumes the L850-GL FCC lock has already been cleared.

Run the prerequisite repo first:

sudo dnf install -y git
git clone https://github.com/fiboromcom/l850gl-fcc-unlock-linux.git
cd l850gl-fcc-unlock-linux
./bootstrap-fedora.sh --yes-i-understand-regulatory-risk

That writes the marker consumed by this repo:

/etc/l850gl-fcc-unlock.done

If the FCC lock was already cleared manually before using this repo:

sudo touch /etc/l850gl-fcc-unlock.done

To bypass the bootstrap check for one run:

SKIP_FCC_PREREQ_CHECK=1 ./bootstrap-fedora.sh

Fresh Fedora bootstrap

After a clean Fedora install, connect with Wi-Fi, Ethernet, or USB tethering first.

sudo dnf install -y git
git clone https://github.com/fiboromcom/l850gl-enable-linux.git
cd l850gl-enable-linux
./bootstrap-fedora.sh

The bootstrap script installs Fedora dependencies, clones the two external source trees into ~/src, installs this recovery bundle, and builds/installs acpi_call for the running kernel.

External repos used by the bootstrap script:

https://github.com/mkottman/acpi_call.git
https://github.com/xmm7360/xmm7360-usb-modeswitch.git

Install

From the extracted directory:

sudo ./install.sh
sudo ./install-acpi-call-module.sh

Then test without reboot:

sudo systemctl reset-failed l850gl-boot-rescue.service
sudo systemctl start l850gl-boot-rescue.service
systemctl status l850gl-boot-rescue.service --no-pager -l

Reboot test:

sudo reboot

After login, wait 60-90 seconds, then:

./diagnostics.sh

Manual fallback

sudo /usr/local/sbin/l850gl-manual-rescue.sh

Boot recovery logs

journalctl -u l850gl-boot-rescue.service -b --no-pager -l
ls -lt /var/log/l850gl-boot-recovery/ | head

Manual Hammer logs

ls -lt /var/log/l850gl-manual-rescue/ | head

Remove boot persistence only

sudo ./uninstall-boot-recovery.sh

This removes:

/etc/systemd/system/l850gl-boot-rescue.service
/usr/local/sbin/l850gl-boot-recovery.sh

It leaves the manual Hammer installed.

Kernel update maintenance

After a kernel update, if boot recovery fails and /proc/acpi/call is missing:

sudo ./install-acpi-call-module.sh

Safety rules

This bundle avoids:

AT+CFUN
AT+COPS
modem NVM writes
native PCI/RPC target path
sleep/resume hooks

Current caveat

Boot recovery is intentionally conservative and may take around 90 seconds.