Linux Kernel 7.1 Removes Major Legacy Ethernet and ISDN Driver

Linus Torvalds has merged a significant set of removal patches into the Linux 7.1 kernel, scheduled for release in mid-June.

The changes eliminate dozens of long-unmaintained Ethernet drivers and entire legacy subsystems, marking one of the largest cleanups of obsolete networking code in recent kernel history.

The removals follow recommendations from Andrew Lunn, the Linux kernel network driver maintainer, and address drivers plagued by accumulating bugs detected by syzbot and AI-based testing tools. With no active maintainers stepping up despite repeated calls on the kernel mailing lists, the maintenance burden had fallen entirely on the core network subsystem team.

Drivers and Subsystems Removed

In addition to the Ethernet drivers initially flagged for removal, the following have been excised:

• ISDN subsystem (entirely)
• AX.25, CAIF, and Bluetooth CMTP (Common ISDN Application Programming Interface Message Transport Protocol) protocol implementations
• yellowfin (Yellowfin Gigabit NIC)
• hamachi (Hamachi GNIC-II)
• hamradio (Amateur Radio subsystem)
• inport and logibm (busmouse) drivers

Remote Ethernet drivers removed include:

• 3com: 3c509, 3c515, 3c574, and 3c589 (EtherLink III, EtherLink XL “Corkscrew,” and “RoadRunner” series)
• amd lance and nmclan (used on HP300, Motorola MVME147 SBC, AMD PCnet32, Allied Telesis AT1500, HP J2405A, and Alchemy Semi AU1X00 platforms)
• smsc smc9194 and smc91c92 (found in DELL laptops with docking stations and various Megahertz, Motorola, Ositech, and Psion Dacom Ethernet cards)
• fujitsu fmvj18x (Fujitsu FMV-J18x chip-based cards)
• 8390-based drivers: AX88190, ultra, and wd80x3 (covering Asix AX88190, NS8390, SMC Ultra, SMC EtherEZ, WD8003/WD8013 chips, including cards from Thomas Conrad and Kingston)

Exceptions and Retained Drivers

Not all proposed removals made the cut. Several Ethernet drivers that were initially targeted for deletion have been retained after community discussion revealed active production use:

• 8390 pcnet
• 3com 3c59x (“Vortex”)
• amd hplance
• amd mvme147
• cirrus cs89x0
• cirrus mac89x0
• xircom xirc2ps (Xircom PCMCIA cards)

The unmaintained Amateur Radio (hamradio) subsystem was removed despite having some users, as most have migrated to modern user-space implementations.

Why Now?

Kernel developers have grown increasingly concerned about the security and stability risk posed by unmaintained legacy code. With syzbot and other automated tools uncovering more bugs each cycle and no volunteers to shoulder the maintenance work, the decision was made to remove the code rather than let it remain as a potential source of vulnerabilities.

This cleanup continues a long-standing trend in the Linux kernel toward removing obsolete drivers and subsystems that no longer have active support, helping keep the kernel leaner and more maintainable for modern hardware and use cases.

Users relying on the removed hardware are advised to explore user-space alternatives or consider upgrading to supported network interfaces. The full list of changes will be detailed in the Linux 7.1 release notes upon its expected mid-June launch.

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