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* [PATCH] Notifier chain update: API changesAlan Stern2006-03-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel's implementation of notifier chains is unsafe. There is no protection against entries being added to or removed from a chain while the chain is in use. The issues were discussed in this thread: http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 We noticed that notifier chains in the kernel fall into two basic usage classes: "Blocking" chains are always called from a process context and the callout routines are allowed to sleep; "Atomic" chains can be called from an atomic context and the callout routines are not allowed to sleep. We decided to codify this distinction and make it part of the API. Therefore this set of patches introduces three new, parallel APIs: one for blocking notifiers, one for atomic notifiers, and one for "raw" notifiers (which is really just the old API under a new name). New kinds of data structures are used for the heads of the chains, and new routines are defined for registration, unregistration, and calling a chain. The three APIs are explained in include/linux/notifier.h and their implementation is in kernel/sys.c. With atomic and blocking chains, the implementation guarantees that the chain links will not be corrupted and that chain callers will not get messed up by entries being added or removed. For raw chains the implementation provides no guarantees at all; users of this API must provide their own protections. (The idea was that situations may come up where the assumptions of the atomic and blocking APIs are not appropriate, so it should be possible for users to handle these things in their own way.) There are some limitations, which should not be too hard to live with. For atomic/blocking chains, registration and unregistration must always be done in a process context since the chain is protected by a mutex/rwsem. Also, a callout routine for a non-raw chain must not try to register or unregister entries on its own chain. (This did happen in a couple of places and the code had to be changed to avoid it.) Since atomic chains may be called from within an NMI handler, they cannot use spinlocks for synchronization. Instead we use RCU. The overhead falls almost entirely in the unregister routine, which is okay since unregistration is much less frequent that calling a chain. Here is the list of chains that we adjusted and their classifications. None of them use the raw API, so for the moment it is only a placeholder. ATOMIC CHAINS ------------- arch/i386/kernel/traps.c: i386die_chain arch/ia64/kernel/traps.c: ia64die_chain arch/powerpc/kernel/traps.c: powerpc_die_chain arch/sparc64/kernel/traps.c: sparc64die_chain arch/x86_64/kernel/traps.c: die_chain drivers/char/ipmi/ipmi_si_intf.c: xaction_notifier_list kernel/panic.c: panic_notifier_list kernel/profile.c: task_free_notifier net/bluetooth/hci_core.c: hci_notifier net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_chain net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_expect_chain net/ipv6/addrconf.c: inet6addr_chain net/netfilter/nf_conntrack_core.c: nf_conntrack_chain net/netfilter/nf_conntrack_core.c: nf_conntrack_expect_chain net/netlink/af_netlink.c: netlink_chain BLOCKING CHAINS --------------- arch/powerpc/platforms/pseries/reconfig.c: pSeries_reconfig_chain arch/s390/kernel/process.c: idle_chain arch/x86_64/kernel/process.c idle_notifier drivers/base/memory.c: memory_chain drivers/cpufreq/cpufreq.c cpufreq_policy_notifier_list drivers/cpufreq/cpufreq.c cpufreq_transition_notifier_list drivers/macintosh/adb.c: adb_client_list drivers/macintosh/via-pmu.c sleep_notifier_list drivers/macintosh/via-pmu68k.c sleep_notifier_list drivers/macintosh/windfarm_core.c wf_client_list drivers/usb/core/notify.c usb_notifier_list drivers/video/fbmem.c fb_notifier_list kernel/cpu.c cpu_chain kernel/module.c module_notify_list kernel/profile.c munmap_notifier kernel/profile.c task_exit_notifier kernel/sys.c reboot_notifier_list net/core/dev.c netdev_chain net/decnet/dn_dev.c: dnaddr_chain net/ipv4/devinet.c: inetaddr_chain It's possible that some of these classifications are wrong. If they are, please let us know or submit a patch to fix them. Note that any chain that gets called very frequently should be atomic, because the rwsem read-locking used for blocking chains is very likely to incur cache misses on SMP systems. (However, if the chain's callout routines may sleep then the chain cannot be atomic.) The patch set was written by Alan Stern and Chandra Seetharaman, incorporating material written by Keith Owens and suggestions from Paul McKenney and Andrew Morton. [jes@sgi.com: restructure the notifier chain initialization macros] Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ibmasm: use after free fixMax Asbock2006-03-09
| | | | | | | | | | | The kobject_put() can free the memory at *cmd, but cmd->lock points to a persistent lock that is not freed with cmd. Signed-off-by: Max Asbock <masbock@us.ibm.com> Cc: Vernon Mauery <vernux@us.ibm.com> Cc: Srihari Vijayaraghavan <sriharivijayaraghavan@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [SERIAL] Remove UPF_AUTOPROBE and UPF_BOOT_ONLYMCARussell King2006-01-21
| | | | | | | | | | | The functionality UPF_BOOT_ONLYMCA provided has been replaced by the 8250_mca module, which only registers MCA ports if MCA is present. UPF_AUTOPROBE has no functional effect - in fact, it's never tested. Only ibmasm set the flag. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Input: ibmasm - fix input initialization error pathDmitry Torokhov2006-01-10
| | | | | | | | | Do not try to free device that has already been unregistered, input_unregister_device() frees it automatically. Spotted by Vernon Mauery <vernux@us.ibm.com> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
* Input: ibmasm - convert to dynamic input_dev allocationVernon Mauery2006-01-07
| | | | | | | | | | | | Update the ibmasm driver to use the dynamic allocation of input_dev structs to work with the sysfs subsystem. Vojtech: Fixed some problems/bugs in the patch. Dmitry: Fixed some more. Signed-off-by: Vernon Mauery <vernux@us.ibm.com> Signed-off-by: Vojtech Pavlik <vojtech@suse.cz> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
* Merge master.kernel.org:/home/rmk/linux-2.6-drvmodelLinus Torvalds2005-11-11
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| * [DRIVER MODEL] Convert platform drivers to use struct platform_driverRussell King2005-11-09
| | | | | | | | | | | | | | | | | | This allows us to eliminate the casts in the drivers, and eventually remove the use of the device_driver function pointer methods for platform device drivers. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
* | [PATCH] changing CONFIG_LOCALVERSION rebuilds too much, for no good reasonOlaf Hering2005-11-09
|/ | | | | | | | | | | | | | | | | | | | | This patch removes almost all inclusions of linux/version.h. The 3 #defines are unused in most of the touched files. A few drivers use the simple KERNEL_VERSION(a,b,c) macro, which is unfortunatly in linux/version.h. There are also lots of #ifdef for long obsolete kernels, this was not touched. In a few places, the linux/version.h include was move to where the LINUX_VERSION_CODE was used. quilt vi `find * -type f -name "*.[ch]"|xargs grep -El '(UTS_RELEASE|LINUX_VERSION_CODE|KERNEL_VERSION|linux/version.h)'|grep -Ev '(/(boot|coda|drm)/|~$)'` search pattern: /UTS_RELEASE\|LINUX_VERSION_CODE\|KERNEL_VERSION\|linux\/\(utsname\|version\).h Signed-off-by: Olaf Hering <olh@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Create platform_device.h to contain all the platform device details.Russell King2005-10-29
| | | | | | | | Convert everyone who uses platform_bus_type to include linux/platform_device.h. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] hdpu_cpustate.c: misc_register() can failChristophe Lucas2005-09-10
| | | | | | | Signed-off-by: Christophe Lucas <clucas@rotomalug.org> Signed-off-by: Domen Puncer <domen@coderock.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [SERIAL] Update ibmasm driver for death of register_serial&coMax Asbock2005-09-07
| | | | | Signed-off-by: Max Asbock <masbock@us.ibm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [ARM] 2866/1: add i.MX set_mctrl / get_mctrl functionsSascha Hauer2005-08-31
| | | | | | | | | | Patch from Sascha Hauer This patch adds support for setting and getting RTS / CTS via set_mtctrl / get_mctrl functions. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] IBM_ASM Kconfig correctionsAdrian Bunk2005-07-12
| | | | | | | | | | | This patch contains the following fixes: - IBM_ASM must depend on PCI - remove useless "default n" - correct the URL to further information Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ibmasm driver: fix race in command refcount logicMax Asbock2005-06-21
| | | | | | | | | | | | | This patch fixes a race in the command reference counting logic by putting spinlocks around kobject_put() in the command_put function. - Also added debug messages. - Changed a memcpy to memcpy_fromio since we are reading from io space. Signed-off-by: Max Asbock <masbock@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ibmasm driver: redesign handling of remote control eventsMax Asbock2005-06-21
| | | | | | | | | | | | | | This patch rewrites the handling of remote control events. Rather than making them available from a special file in the ibmasmfs, now the events from the RSA card get translated into kernel input events and injected into the input subsystem. The driver now will generate two /dev/input/eventX nodes -- one for the keyboard and one for the mouse. The mouse node generates absolute events more like a touch pad than a mouse. Signed-off-by: Vernon Mauery <vernux@us.ibm.com> Signed-off-by: Max Asbock <masbock@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ibmasm driver: correctly wake up sleeping threadsMax Asbock2005-06-21
| | | | | | | | | | Due to my incomplete understanding of the wait_event_interruptible() function threads waiting for service processor events were not woken up. This patch fixes that problem. Signed-off-by: Max Asbock <masbock@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ibmasm driver: fix command buffer sizeMax Asbock2005-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | First of a series of patches for the ibmasm driver. (that is the driver for the IBM xSeries RSA service processor) To summarize what they do: [1] change a #define for the buffer size for commands [2] Fix a bug where threads in the event handling code calling wait_event_interruptible() weren't woken up as expected. [3] Redesigned how remote mouse and keyboard events received by the driver are handled. [4] Fixed a race in the command reference counting logic. This patch: - change a #define for the buffer size for commands Signed-off-by: Max Asbock <masbock@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-16
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!