The following is a list of files and features that are going to be removed in the kernel source tree. Every entry should contain what exactly is going away, why it is happening, and who is going to be doing the work. When the feature is removed from the kernel, it should also be removed from this file. --------------------------- What: devfs When: July 2005 Files: fs/devfs/*, include/linux/devfs_fs*.h and assorted devfs function calls throughout the kernel tree Why: It has been unmaintained for a number of years, has unfixable races, contains a naming policy within the kernel that is against the LSB, and can be replaced by using udev. Who: Greg Kroah-Hartman --------------------------- What: RAW driver (CONFIG_RAW_DRIVER) When: December 2005 Why: declared obsolete since kernel 2.6.3 O_DIRECT can be used instead Who: Adrian Bunk --------------------------- What: drivers that were depending on OBSOLETE_OSS_DRIVER (config options already removed) When: before 2.6.19 Why: OSS drivers with ALSA replacements Who: Adrian Bunk --------------------------- What: RCU API moves to EXPORT_SYMBOL_GPL When: April 2006 Files: include/linux/rcupdate.h, kernel/rcupdate.c Why: Outside of Linux, the only implementations of anything even vaguely resembling RCU that I am aware of are in DYNIX/ptx, VM/XA, Tornado, and K42. I do not expect anyone to port binary drivers or kernel modules from any of these, since the first two are owned by IBM and the last two are open-source research OSes. So these will move to GPL after a grace period to allow people, who might be using implementations that I am not aware of, to adjust to this upcoming change. Who: Paul E. McKenney --------------------------- What: raw1394: requests of type RAW1394_REQ_ISO_SEND, RAW1394_REQ_ISO_LISTEN When: November 2005 Why: Deprecated in favour of the new ioctl-based rawiso interface, which is more efficient. You should really be using libraw1394 for raw1394 access anyway. Who: Jody McIntyre --------------------------- What: sbp2: module parameter "force_inquiry_hack" When: July 2006 Why: Superceded by parameter "workarounds". Both parameters are meant to be used ad-hoc and for single devices only, i.e. not in modprobe.conf, therefore the impact of this feature replacement should be low. Who: Stefan Richter --------------------------- What: Video4Linux API 1 ioctls and video_decoder.h from Video devices. When: July 2006 Why: V4L1 AP1 was replaced by V4L2 API. during migration from 2.4 to 2.6 series. The old API have lots of drawbacks and don't provide enough means to work with all video and audio standards. The newer API is already available on the main drivers and should be used instead. Newer drivers should use v4l_compat_translate_ioctl function to handle old calls, replacing to newer ones. Decoder iocts are using internally to allow video drivers to communicate with video decoders. This should also be improved to allow V4L2 calls being translated into compatible internal ioctls. Who: Mauro Carvalho Chehab --------------------------- What: remove EXPORT_SYMBOL(insert_resource) When: April 2006 Files: kernel/resource.c Why: No modular usage in the kernel. Who: Adrian Bunk --------------------------- What: PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl]) When: November 2005 Files: drivers/pcmcia/: pcmcia_ioctl.c Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a normal hotpluggable bus, and with it using the default kernel infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA control ioctl needed by cardmgr and cardctl from pcmcia-cs is unnecessary, and makes further cleanups and integration of the PCMCIA subsystem into the Linux kernel device driver model more difficult. The features provided by cardmgr and cardctl are either handled by the kernel itself now or are available in the new pcmciautils package available at http://kernel.org/pub/linux/utils/kernel/pcmcia/ Who: Dominik Brodowski --------------------------- What: ip_queue and ip6_queue (old ipv4-only and ipv6-only netfilter queue) When: December 2005 Why: This interface has been obsoleted by the new layer3-independent "nfnetlink_queue". The Kernel interface is compatible, so the old ip[6]tables "QUEUE" targets still work and will transparently handle all packets into nfnetlink queue number 0. Userspace users will have to link against API-compatible library on top of libnfnetlink_queue instead of the current 'libipq'. Who: Harald Welte --------------------------- What: remove EXPORT_SYMBOL(kernel_thread) When: August 2006 Files: arch/*/kernel/*_ksyms.c Why: kernel_thread is a low-level implementation detail. Drivers should use the API instead which shields them from implementation details and provides a higherlevel interface that prevents bugs and code duplication Who: Christoph Hellwig --------------------------- What: CONFIG_FORCED_INLINING When: June 2006 Why: Config option is there to see if gcc is good enough. (in january 2006). If it is, the behavior should just be the default. If it's not, the option should just go away entirely. Who: Arjan van de Ven --------------------------- What: START_ARRAY ioctl for md When: July 2006 Files: drivers/md/md.c Why: Not reliable by design - can fail when most needed. Alternatives exist Who: NeilBrown --------------------------- What: au1x00_uart driver When: January 2006 Why: The 8250 serial driver now has the ability to deal with the differences between the standard 8250 family of UARTs and their slightly strange brother on Alchemy SOCs. The loss of features is not considered an issue. Who: Ralf Baechle --------------------------- What: eepro100 network driver When: January 2007 Why: replaced by the e100 driver Who: Adrian Bunk --------------------------- What: pci_module_init(driver) When: January 2007 Why: Is replaced by pci_register_driver(pci_driver). Who: Richard Knutsson and Greg Kroah-Hartman --------------------------- What: Usage of invalid timevals in setitimer When: March 2007 Why: POSIX requires to validate timevals in the setitimer call. This was never done by Linux. The invalid (e.g. negative timevals) were silently converted to more or less random timeouts and intervals. Until the removal a per boot limited number of warnings is printed and the timevals are sanitized. Who: Thomas Gleixner --------------------------- What: I2C interface of the it87 driver When: January 2007 Why: The ISA interface is faster and should be always available. The I2C probing is also known to cause trouble in at least one case (see bug #5889.) Who: Jean Delvare --------------------------- What: remove EXPORT_SYMBOL(tasklist_lock) When: August 2006 Files: kernel/fork.c Why: tasklist_lock protects the kernel internal task list. Modules have no business looking at it, and all instances in drivers have been due to use of too-lowlevel APIs. Having this symbol exported prevents moving to more scalable locking schemes for the task list. Who: Christoph Hellwig --------------------------- What: mount/umount uevents When: February 2007 Why: These events are not correct, and do not properly let userspace know when a file system has been mounted or unmounted. Userspace should poll the /proc/mounts file instead to detect this properly. Who: Greg Kroah-Hartman --------------------------- What: USB driver API moves to EXPORT_SYMBOL_GPL When: Febuary 2008 Files: include/linux/usb.h, drivers/usb/core/driver.c Why: The USB subsystem has changed a lot over time, and it has been possible to create userspace USB drivers using usbfs/libusb/gadgetfs that operate as fast as the USB bus allows. Because of this, the USB subsystem will not be allowing closed source kernel drivers to register with it, after this grace period is over. If anyone needs any help in converting their closed source drivers over to use the userspace filesystems, please contact the linux-usb-devel@lists.sourceforge.net mailing list, and the developers there will be glad to help you out. Who: Greg Kroah-Hartman --------------------------- What: find_trylock_page When: January 2007 Why: The interface no longer has any callers left in the kernel. It is an odd interface (compared with other find_*_page functions), in that it does not take a refcount to the page, only the page lock. It should be replaced with find_get_page or find_lock_page if possible. This feature removal can be reevaluated if users of the interface cannot cleanly use something else. Who: Nick Piggin ---------------------------