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: /sys/devices/.../power/state dev->power.power_state dpm_runtime_{suspend,resume)() When: July 2007 Why: Broken design for runtime control over driver power states, confusing driver-internal runtime power management with: mechanisms to support system-wide sleep state transitions; event codes that distinguish different phases of swsusp "sleep" transitions; and userspace policy inputs. This framework was never widely used, and most attempts to use it were broken. Drivers should instead be exposing domain-specific interfaces either to kernel or to userspace. Who: Pavel Machek --------------------------- 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: raw1394: requests of type RAW1394_REQ_ISO_SEND, RAW1394_REQ_ISO_LISTEN When: November 2006 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: Video4Linux API 1 ioctls and video_decoder.h from Video devices. When: December 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: sys_sysctl When: January 2007 Why: The same information is available through /proc/sys and that is the interface user space prefers to use. And there do not appear to be any existing user in user space of sys_sysctl. The additional maintenance overhead of keeping a set of binary names gets in the way of doing a good job of maintaining this interface. Who: Eric Biederman --------------------------- 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: eepro100 network driver When: January 2007 Why: replaced by the e100 driver Who: Adrian Bunk --------------------------- What: drivers depending on OSS_OBSOLETE_DRIVER When: options in 2.6.20, code in 2.6.22 Why: OSS drivers with ALSA replacements 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: Unused EXPORT_SYMBOL/EXPORT_SYMBOL_GPL exports (temporary transition config option provided until then) The transition config option will also be removed at the same time. When: before 2.6.19 Why: Unused symbols are both increasing the size of the kernel binary and are often a sign of "wrong API" Who: Arjan van de Ven --------------------------- 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 --------------------------- What: Support for the IT8172-based platforms, ITE 8172G and Globespan IVR When: September 2006 Why: Code does no longer build since at least 2.6.0, apparently there is no user base left for these platforms. Hardware out of production since several years and hardly a trace of the manufacturer left on the net. Who: Ralf Baechle --------------------------- What: Interrupt only SA_* flags When: Januar 2007 Why: The interrupt related SA_* flags are replaced by IRQF_* to move them out of the signal namespace. Who: Thomas Gleixner --------------------------- What: i2c-ite and i2c-algo-ite drivers When: September 2006 Why: These drivers never compiled since they were added to the kernel tree 5 years ago. This feature removal can be reevaluated if someone shows interest in the drivers, fixes them and takes over maintenance. http://marc.theaimsgroup.com/?l=linux-mips&m=115040510817448 Who: Jean Delvare --------------------------- What: Bridge netfilter deferred IPv4/IPv6 output hook calling When: January 2007 Why: The deferred output hooks are a layering violation causing unusual and broken behaviour on bridge devices. Examples of things they break include QoS classifation using the MARK or CLASSIFY targets, the IPsec policy match and connection tracking with VLANs on a bridge. Their only use is to enable bridge output port filtering within iptables with the physdev match, which can also be done by combining iptables and ebtables using netfilter marks. Until it will get removed the hook deferral is disabled by default and is only enabled when needed. Who: Patrick McHardy --------------------------- What: frame diverter When: November 2006 Why: The frame diverter is included in most distribution kernels, but is broken. It does not correctly handle many things: - IPV6 - non-linear skb's - network device RCU on removal - input frames not correctly checked for protocol errors It also adds allocation overhead even if not enabled. It is not clear if anyone is still using it. Who: Stephen Hemminger --------------------------- What: PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment When: Oktober 2008 Why: The stacking of class devices makes these values misleading and inconsistent. Class devices should not carry any of these properties, and bus devices have SUBSYTEM and DRIVER as a replacement. Who: Kay Sievers --------------------------- What: i2c-isa When: December 2006 Why: i2c-isa is a non-sense and doesn't fit in the device driver model. Drivers relying on it are better implemented as platform drivers. Who: Jean Delvare --------------------------- What: ftape When: 2.6.20 Why: Orphaned for ages. SMP bugs long unfixed. Few users left in the world. Who: Jeff Garzik ---------------------------