aboutsummaryrefslogtreecommitdiff
path: root/init
AgeCommit message (Collapse)Author
2008-07-22make CONFIG_KMOD invisibleJohannes Berg
... as preparation for removing it completely, make it an invisible bool defaulting to yes. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefsDenys Vlasenko
module.c and module.h conatains code for finding exported symbols which are declared with EXPORT_UNUSED_SYMBOL, and this code is compiled in even if CONFIG_UNUSED_SYMBOLS is not set and thus there can be no EXPORT_UNUSED_SYMBOLs in modules anyway (because EXPORT_UNUSED_SYMBOL(x) are compiled out to nothing then). This patch adds required #ifdefs. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-20initrd: Fix virtual/physical mix-up in overwrite testGeert Uytterhoeven
On recent kernels, I get the following error when using an initrd: | initrd overwritten (0x00b78000 < 0x07668000) - disabling it. My Amiga 4000 has 12 MiB of RAM at physical address 0x07400000 (virtual 0x00000000). The initrd is located at the end of RAM: 0x00b78000 - 0x00c00000 (virtual). The overwrite test compares the (virtual) initrd location to the (physical) first available memory location, which fails. This patch converts initrd_start to a page frame number, so it can safely be compared with min_low_pfn. Before the introduction of discontiguous memory support on m68k (12d810c1b8c2b913d48e629e2b5c01d105029839), min_low_pfn was just left untouched by the m68k-specific code (zero, I guess), and everything worked fine. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-16Merge branch 'for_linus' of git://git.infradead.org/~dedekind/ubifs-2.6Linus Torvalds
* 'for_linus' of git://git.infradead.org/~dedekind/ubifs-2.6: UBIFS: include to compilation UBIFS: add new flash file system UBIFS: add brief documentation MAINTAINERS: add UBIFS section do_mounts: allow UBI root device name VFS: export sync_sb_inodes VFS: move inode_lock into sync_sb_inodes
2008-07-15Merge branch 'generic-ipi-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (22 commits) generic-ipi: more merge fallout generic-ipi: merge fix x86, visws: use mach-default/entry_arch.h x86, visws: fix generic-ipi build generic-ipi: fixlet generic-ipi: fix s390 build bug generic-ipi: fix linux-next tree build failure fix: "smp_call_function: get rid of the unused nonatomic/retry argument" fix: "smp_call_function: get rid of the unused nonatomic/retry argument" fix "smp_call_function: get rid of the unused nonatomic/retry argument" on_each_cpu(): kill unused 'retry' parameter smp_call_function: get rid of the unused nonatomic/retry argument sh: convert to generic helpers for IPI function calls parisc: convert to generic helpers for IPI function calls mips: convert to generic helpers for IPI function calls m32r: convert to generic helpers for IPI function calls arm: convert to generic helpers for IPI function calls alpha: convert to generic helpers for IPI function calls ia64: convert to generic helpers for IPI function calls powerpc: convert to generic helpers for IPI function calls ... Fix trivial conflicts due to rcu updates in kernel/rcupdate.c manually
2008-07-15Merge branch 'generic-ipi' into generic-ipi-for-linusIngo Molnar
Conflicts: arch/powerpc/Kconfig arch/s390/kernel/time.c arch/x86/kernel/apic_32.c arch/x86/kernel/cpu/perfctr-watchdog.c arch/x86/kernel/i8259_64.c arch/x86/kernel/ldt.c arch/x86/kernel/nmi_64.c arch/x86/kernel/smpboot.c arch/x86/xen/smp.c include/asm-x86/hw_irq_32.h include/asm-x86/hw_irq_64.h include/asm-x86/mach-default/irq_vectors.h include/asm-x86/mach-voyager/irq_vectors.h include/asm-x86/smp.h kernel/Makefile Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15Merge branch 'core/rcu' into core/rcu-for-linusIngo Molnar
2008-07-14do_mounts: allow UBI root device nameAdrian Hunter
Similarly to MTD devices, allow UBI devices. Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-06-26Add generic helpers for arch IPI function callsJens Axboe
This adds kernel/smp.c which contains helpers for IPI function calls. In addition to supporting the existing smp_call_function() in a more efficient manner, it also adds a more scalable variant called smp_call_function_single() for calling a given function on a single CPU only. The core of this is based on the x86-64 patch from Nick Piggin, lots of changes since then. "Alan D. Brunelle" <Alan.Brunelle@hp.com> has contributed lots of fixes and suggestions as well. Also thanks to Paul E. McKenney <paulmck@linux.vnet.ibm.com> for reviewing RCU usage and getting rid of the data allocation fallback deadlock. Acked-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-24x86: use cpu_khz for loops_per_jiffy calculation, cleanupAlok Kataria
As suggested by Ingo, remove all references to tsc from init/calibrate.c TSC is x86 specific, and using tsc in variable names in a generic file should be avoided. lpj_tsc is now called lpj_fine, since it is related to fine tuning of lpj value. Also tsc_rate_* is called timer_rate_* Signed-off-by: Alok N Kataria <akataria@vmware.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Daniel Hecht <dhecht@vmware.com> Cc: Tim Mann <mann@vmware.com> Cc: Zach Amsden <zach@vmware.com> Cc: Sahil Rihan <srihan@vmware.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-23x86: use cpu_khz for loops_per_jiffy calculationAlok Kataria
On the x86 platform we can use the value of tsc_khz computed during tsc calibration to calculate the loops_per_jiffy value. Its very important to keep the error in lpj values to minimum as any error in that may result in kernel panic in check_timer. In virtualization environment, On a highly overloaded host the guest delay calibration may sometimes result in errors beyond the ~50% that timer_irq_works can handle, resulting in the guest panicking. Does some formating changes to lpj_setup code to now have a single printk to print the bogomips value. We do this only for the boot processor because the AP's can have different base frequencies or the BIOS might boot a AP at a different frequency. Signed-off-by: Alok N Kataria <akataria@vmware.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Daniel Hecht <dhecht@vmware.com> Cc: Tim Mann <mann@vmware.com> Cc: Zach Amsden <zach@vmware.com> Cc: Sahil Rihan <srihan@vmware.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-16Merge branch 'linus' into core/rcuIngo Molnar
2008-05-25Kconfig: introduce ARCH_DEFCONFIG to DEFCONFIG_LISTSam Ravnborg
init/Kconfig contains a list of configs that are searched for if 'make *config' are used with no .config present. Extend this list to look at the config identified by ARCH_DEFCONFIG. With this change we now try the defconfig targets last. This fixes a regression reported by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com>
2008-05-24md: proper extern for mdp_majorAdrian Bunk
This patch adds a proper extern for mdp_major in include/linux/raid/md.h Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-19rcu: add call_rcu_sched()Paul E. McKenney
Fourth cut of patch to provide the call_rcu_sched(). This is again to synchronize_sched() as call_rcu() is to synchronize_rcu(). Should be fine for experimental and -rt use, but not ready for inclusion. With some luck, I will be able to tell Andrew to come out of hiding on the next round. Passes multi-day rcutorture sessions with concurrent CPU hotplugging. Fixes since the first version include a bug that could result in indefinite blocking (spotted by Gautham Shenoy), better resiliency against CPU-hotplug operations, and other minor fixes. Fixes since the second version include reworking grace-period detection to avoid deadlocks that could happen when running concurrently with CPU hotplug, adding Mathieu's fix to avoid the softlockup messages, as well as Mathieu's fix to allow use earlier in boot. Fixes since the third version include a wrong-CPU bug spotted by Andrew, getting rid of the obsolete synchronize_kernel API that somehow snuck back in, merging spin_unlock() and local_irq_restore() in a few places, commenting the code that checks for quiescent states based on interrupting from user-mode execution or the idle loop, removing some inline attributes, and some code-style changes. Known/suspected shortcomings: o I still do not entirely trust the sleep/wakeup logic. Next step will be to use a private snapshot of the CPU online mask in rcu_sched_grace_period() -- if the CPU wasn't there at the start of the grace period, we don't need to hear from it. And the bit about accounting for changes in online CPUs inside of rcu_sched_grace_period() is ugly anyway. o It might be good for rcu_sched_grace_period() to invoke resched_cpu() when a given CPU wasn't responding quickly, but resched_cpu() is declared static... This patch also fixes a long-standing bug in the earlier preemptable-RCU implementation of synchronize_rcu() that could result in loss of concurrent external changes to a task's CPU affinity mask. I still cannot remember who reported this... Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-15initcalls: Fix m68k build and possible buffer overflowCyrill Gorcunov
This patch fixes a build bug on m68k - gcc decides to emit a call to the strlen library function, which we don't implement. More importantly - my previous patch "init: don't lose initcall return values" (commit e662e1cfd434aa234b72fbc781f1d70211cb785b) had introduced potential buffer overflow by wrong calculation of string accumulator size. Use strlcat() instead, fixing both bugs. Many thanks Andreas Schwab and Geert Uytterhoeven for helping to catch and fix the bug. Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-15Split up 'do_initcalls()' into two simpler functionsLinus Torvalds
One function to just loop over the entries, one function to actually do the call and the associated debugging code. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-15Clean up 'print_fn_descriptor_symbol()' typesLinus Torvalds
Everybody wants to pass it a function pointer, and in fact, that is what you _must_ pass it for it to make sense (since it knows that ia64 and ppc64 use descriptors for function pointers and fetches the actual address from there). So don't make the argument be a 'unsigned long' and force everybody to add a cast. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14block: do_mounts - accept root=<non-existant partition>Kay Sievers
Some devices, like md, may create partitions only at first access, so allow root= to be set to a valid non-existant partition of an existing disk. This applies only to non-initramfs root mounting. This fixes a regression from 2.6.24 which did allow this to happen and broke some users machines :( Acked-by: Neil Brown <neilb@suse.de> Tested-by: Joao Luis Meloni Assirati <assirati@nonada.if.usp.br> Cc: stable <stable@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-05-13init: don't lose initcall return valuesCyrill Gorcunov
There is an ability to lose an initcall return value if it happened with irq disabled or imbalanced preemption (and if we debug initcall). Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-09module: don't ignore vermagic string if module doesn't have modversionsRusty Russell
Linus found a logic bug: we ignore the version number in a module's vermagic string if we have CONFIG_MODVERSIONS set, but modversions also lets through a module with no __versions section for modprobe --force (with tainting, but still). We should only ignore the start of the vermagic string if the module actually *has* crcs to check. Rather than (say) having an entertaining hissy fit and creating a config option to work around the buggy code. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-07pcspkr: fix dependanciesStas Sergeev
fix pcspkr dependancies: make the pcspkr platform drivers to depend on a platform device, and not the other way around. Signed-off-by: Stas Sergeev <stsp@aknet.ru> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Dmitry Torokhov <dtor@mail.ru> CC: Vojtech Pavlik <vojtech@suse.cz> CC: Michael Opdenacker <michael-lists@free-electrons.com> [fixed for 2.6.26-rc1 by tiwai] Signed-off-by: Takashi Iwai <tiwai@suse.de>
2008-05-05sched: default to n for GROUP_SCHED and FAIR_GROUP_SCHEDParag Warudkar
GROUP_SCHED is confirmed to cause unacceptable latencies, see: http://lkml.org/lkml/2008/5/2/370. Mark it EXPERIMENTAL and default to no for now. Signed-off-by: Parag Warudkar <parag.warudkar@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-05sched: add optional support for CONFIG_HAVE_UNSTABLE_SCHED_CLOCKPeter Zijlstra
this replaces the rq->clock stuff (and possibly cpu_clock()). - architectures that have an 'imperfect' hardware clock can set CONFIG_HAVE_UNSTABLE_SCHED_CLOCK - the 'jiffie' window might be superfulous when we update tick_gtod before the __update_sched_clock() call in sched_clock_tick() - cpu_clock() might be implemented as: sched_clock_cpu(smp_processor_id()) if the accuracy proves good enough - how far can TSC drift in a single jiffie when considering the filtering and idle hooks? [ mingo@elte.hu: various fixes and cleanups ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-05sched, x86: add HAVE_UNSTABLE_SCHED_CLOCKIngo Molnar
add the HAVE_UNSTABLE_SCHED_CLOCK, for architectures to select. the next change utilizes it. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-04Make forced module loading optionalLinus Torvalds
The kernel module loader used to be much too happy to allow loading of modules for the wrong kernel version by default. For example, if you had MODVERSIONS enabled, but tried to load a module with no version info, it would happily load it and taint the kernel - whether it was likely to actually work or not! Generally, such forced module loading should be considered a really really bad idea, so make it conditional on a new config option (MODULE_FORCE_LOAD), and make it default to off. If somebody really wants to force module loads, that's their problem, but we should not encourage it. Especially as it happened to me by mistake (ie regular unversioned Fedora modules getting loaded) causing lots of strange behavior. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-02slub: #ifdef simplificationChristoph Lameter
If we make SLUB_DEBUG depend on SYSFS then we can simplify some #ifdefs and avoid others. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2008-04-30infrastructure to debug (dynamic) objectsThomas Gleixner
We can see an ever repeating problem pattern with objects of any kind in the kernel: 1) freeing of active objects 2) reinitialization of active objects Both problems can be hard to debug because the crash happens at a point where we have no chance to decode the root cause anymore. One problem spot are kernel timers, where the detection of the problem often happens in interrupt context and usually causes the machine to panic. While working on a timer related bug report I had to hack specialized code into the timer subsystem to get a reasonable hint for the root cause. This debug hack was fine for temporary use, but far from a mergeable solution due to the intrusiveness into the timer code. The code further lacked the ability to detect and report the root cause instantly and keep the system operational. Keeping the system operational is important to get hold of the debug information without special debugging aids like serial consoles and special knowledge of the bug reporter. The problems described above are not restricted to timers, but timers tend to expose it usually in a full system crash. Other objects are less explosive, but the symptoms caused by such mistakes can be even harder to debug. Instead of creating specialized debugging code for the timer subsystem a generic infrastructure is created which allows developers to verify their code and provides an easy to enable debug facility for users in case of trouble. The debugobjects core code keeps track of operations on static and dynamic objects by inserting them into a hashed list and sanity checking them on object operations and provides additional checks whenever kernel memory is freed. The tracked object operations are: - initializing an object - adding an object to a subsystem list - deleting an object from a subsystem list Each operation is sanity checked before the operation is executed and the subsystem specific code can provide a fixup function which allows to prevent the damage of the operation. When the sanity check triggers a warning message and a stack trace is printed. The list of operations can be extended if the need arises. For now it's limited to the requirements of the first user (timers). The core code enqueues the objects into hash buckets. The hash index is generated from the address of the object to simplify the lookup for the check on kfree/vfree. Each bucket has it's own spinlock to avoid contention on a global lock. The debug code can be compiled in without being active. The runtime overhead is minimal and could be optimized by asm alternatives. A kernel command line option enables the debugging code. Thanks to Ingo Molnar for review, suggestions and cleanup patches. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30Deprecate find_task_by_pid()Pavel Emelyanov
There are some places that are known to operate on tasks' global pids only: * the rest_init() call (called on boot) * the kgdb's getthread * the create_kthread() (since the kthread is run in init ns) So use the find_task_by_pid_ns(..., &init_pid_ns) there and schedule the find_task_by_pid for removal. [sukadev@us.ibm.com: Fix warning in kernel/pid.c] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30signals: fix /sbin/init protection from unwanted signalsOleg Nesterov
The global init has a lot of long standing problems with the unhandled fatal signals. - The "is_global_init(current)" check in get_signal_to_deliver() protects only the main thread. Sub-thread can dequee the fatal signal and shutdown the whole thread group except the main thread. If it dequeues SIGSTOP /sbin/init will be stopped, this is not right too. Note that we can't use is_global_init(->group_leader), this breaks exec and this can't solve other problems we have. - Even if afterwards ignored, the fatal signals sets SIGNAL_GROUP_EXIT on delivery. This breaks exec, has other bad implications, and this is just wrong. Introduce the new SIGNAL_UNKILLABLE flag to fix these problems. It also helps to solve some other problems addressed by the subsequent patches. Currently we use this flag for the global init only, but it could also be used by kthreads and (perhaps) by the sub-namespace inits. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29idr: create idr_layer_cache at boot timeAkinobu Mita
Avoid a possible kmem_cache_create() failure by creating idr_layer_cache unconditionary at boot time rather than creating it on-demand when idr_init() is called the first time. This change also enables us to eliminate the check every time idr_init() is called. [akpm@linux-foundation.org: rename init_id_cache() to idr_init_cache()] [akpm@linux-foundation.org: fix alpha build] Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29sysctl: allow embedded targets to disable sysctl_check.cHolger Schurig
Disable sysctl_check.c for embedded targets. This saves about about 11 kB in .text and another 11 kB in .data on a PXA255 embedded platform. Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29cgroups: add an owner to the mm_structBalbir Singh
Remove the mem_cgroup member from mm_struct and instead adds an owner. This approach was suggested by Paul Menage. The advantage of this approach is that, once the mm->owner is known, using the subsystem id, the cgroup can be determined. It also allows several control groups that are virtually grouped by mm_struct, to exist independent of the memory controller i.e., without adding mem_cgroup's for each controller, to mm_struct. A new config option CONFIG_MM_OWNER is added and the memory resource controller selects this config option. This patch also adds cgroup callbacks to notify subsystems when mm->owner changes. The mm_cgroup_changed callback is called with the task_lock() of the new task held and is called just prior to changing the mm->owner. I am indebted to Paul Menage for the several reviews of this patchset and helping me make it lighter and simpler. This patch was tested on a powerpc box, it was compiled with both the MM_OWNER config turned on and off. After the thread group leader exits, it's moved to init_css_state by cgroup_exit(), thus all future charges from runnings threads would be redirected to the init_css_set's subsystem. Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: Pavel Emelianov <xemul@openvz.org> Cc: Hugh Dickins <hugh@veritas.com> Cc: Sudhir Kumar <skumar@linux.vnet.ibm.com> Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp> Cc: Hirokazu Takahashi <taka@valinux.co.jp> Cc: David Rientjes <rientjes@google.com>, Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Reviewed-by: Paul Menage <menage@google.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29cgroups: implement device whitelistSerge E. Hallyn
Implement a cgroup to track and enforce open and mknod restrictions on device files. A device cgroup associates a device access whitelist with each cgroup. A whitelist entry has 4 fields. 'type' is a (all), c (char), or b (block). 'all' means it applies to all types and all major and minor numbers. Major and minor are either an integer or * for all. Access is a composition of r (read), w (write), and m (mknod). The root device cgroup starts with rwm to 'all'. A child devcg gets a copy of the parent. Admins can then remove devices from the whitelist or add new entries. A child cgroup can never receive a device access which is denied its parent. However when a device access is removed from a parent it will not also be removed from the child(ren). An entry is added using devices.allow, and removed using devices.deny. For instance echo 'c 1:3 mr' > /cgroups/1/devices.allow allows cgroup 1 to read and mknod the device usually known as /dev/null. Doing echo a > /cgroups/1/devices.deny will remove the default 'a *:* mrw' entry. CAP_SYS_ADMIN is needed to change permissions or move another task to a new cgroup. A cgroup may not be granted more permissions than the cgroup's parent has. Any task can move itself between cgroups. This won't be sufficient, but we can decide the best way to adequately restrict movement later. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix may-be-used-uninitialized warning] Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Acked-by: James Morris <jmorris@namei.org> Looks-good-to: Pavel Emelyanov <xemul@openvz.org> Cc: Daniel Hokka Zakrisson <daniel@hozac.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29CGroup API files: make CGROUP_DEBUG default to offPaul Menage
The cgroup debug subsystem isn't generally useful for users. It should default to "n". Signed-off-by: Paul Menage <menage@google.com> Cc: "Li Zefan" <lizf@cn.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: "YAMAMOTO Takashi" <yamamoto@valinux.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29directly use kmalloc() and kfree() in init/initramfs.cThomas Petazzoni
Instead of using the malloc() and free() wrappers needed by the lib/inflate.c code for allocations, simply use kmalloc() and kfree() in the initramfs code. This is needed for a further lib/inflate.c-related cleanup patch that will remove the malloc() and free() functions. Take that opportunity to remove the useless kmalloc() return value cast. Based on work done by Matt Mackall. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Signed-off-by: Matt Mackall <mpm@selenic.com> Cc: Jan Engelhardt <jengelh@computergmbh.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29Simplify initcall_debug outputBjorn Helgaas
print_fn_descriptor_symbol() prints the address if we don't have a symbol, so no need to print both. Also, combine printing return value with elapsed time. Changes this: Calling initcall 0xc05b7a70: pci_mmcfg_late_insert_resources+0x0/0x50() initcall 0xc05b7a70: pci_mmcfg_late_insert_resources+0x0/0x50() returned 1. initcall 0xc05b7a70 ran for 0 msecs: pci_mmcfg_late_insert_resources+0x0/0x50() initcall at 0xc05b7a70: pci_mmcfg_late_insert_resources+0x0/0x50(): returned with error code 1 to this: calling pci_mmcfg_late_insert_resources+0x0/0x50() initcall pci_mmcfg_late_insert_resources+0x0/0x50() returned 1 after 0 msecs initcall pci_mmcfg_late_insert_resources+0x0/0x50() returned with error code 1 Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29let LOG_BUF_SHIFT default to 17Adrian Bunk
16 kB is often no longer enough for a normal boot of an UP system. And even less when people e.g. use suspend. 17 seems to be a more reasonable default for current kernels on current hardware (it's just the default, anyone who is memory limited can still lower it). Signed-off-by: Adrian Bunk <bunk@kernel.org> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28init: fix integer as NULL pointer warningsHarvey Harrison
init/do_mounts_rd.c:215:13: warning: Using plain integer as NULL pointer init/do_mounts_md.c:136:45: warning: Using plain integer as NULL pointer Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: sparc: video drivers: add facility level sparc: tcx.c make tcx_init and tcx_exit static sparc: ffb.c make ffb_init and ffb_exit static sparc: cg14.c make cg14_init and cg15_exit static sparc: bw2.c fix bw2_exit sparc64: Fix accidental syscall restart on child return from clone/fork/vfork. sparc64: Clean up handling of pt_regs trap type encoding. sparc: Remove old style signal frame support. sparc64: Kill bogus RT_ALIGNEDSZ macro from signal.c sparc: sunzilog.c remove unused argument sparc: fix drivers/video/tcx.c warning sparc64: Kill unused local ISA bus layer. input: Rewrite sparcspkr device probing. sparc64: Do not ignore 'pmu' device ranges. sparc64: Kill ISA_FLOPPY_WORKS code. sparc64: Kill CONFIG_SPARC32_COMPAT sparc64: Cleanups and corrections for arch/sparc64/Kconfig sparc64: Fix wedged irq regression.
2008-04-28make CC_OPTIMIZE_FOR_SIZE non-experimentalIngo Molnar
this option has been the default on a wide range of distributions for a long time - time to make it non-experimental. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-26sparc64: Kill CONFIG_SPARC32_COMPATDavid S. Miller
It's completely superfluous, CONFIG_COMPAT is sufficient. What this used to be is an umbrella for enabling code shared by all 32-bit compat binary support types. But with the removal of SunOS and Solaris support, the only one left is Linux 32-bit ELF. Update defconfig. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-24[POWERPC] Use __weak macro for smp_setup_processor_idBenjamin Herrenschmidt
Use the __weak macro instead of the longer __attribute__ ((weak)) form in one place in init/main.c. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Andrew Morton <akpm@linux-foundation.org> -- init/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24[POWERPC] Add thread_info_cache_init() weak hookBenjamin Herrenschmidt
Some architectures need to maintain a kmem cache for thread info structures. The next commit adds that to powerpc to fix an alignment problem. There is no good arch callback to use to initialize that cache that I can find, so this adds a new one in the form of a weak function whose default is empty. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-19sched: better rt-group documentationViktor Radnai
Viktor was nice enough to enhance the document based on my replies to his questions on the subject. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19init: move setup of nr_cpu_ids to as early as possibleMike Travis
Move the setting of nr_cpu_ids from sched_init() to start_kernel() so that it's available as early as possible. Note that an arch has the option of setting it even earlier if need be, but it should not result in a different value than the setup_nr_cpu_ids() function. Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19cpumask: add CPU_MASK_ALL_PTR macroMike Travis
* Add a static cpumask_t variable "CPU_MASK_ALL_PTR" to use as a pointer reference to CPU_MASK_ALL. This reduces where possible the instances where CPU_MASK_ALL allocates and fills a large array on the stack. Used only if NR_CPUS > BITS_PER_LONG. * Change init/main.c to use new set_cpus_allowed_ptr(). Depends on: [sched-devel]: sched: add new set_cpus_allowed_ptr function Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-14slub: No need for per node slab counters if !SLUB_DEBUGChristoph Lameter
The per node counters are used mainly for showing data through the sysfs API. If that API is not compiled in then there is no point in keeping track of this data. Disable counters for the number of slabs and the number of total slabs if !SLUB_DEBUG. Incrementing the per node counters is also accessing a potentially contended cacheline so this could actually be a performance benefit to embedded systems. SLABINFO support is also affected. It now must depends on SLUB_DEBUG (which is on by default). Patch also avoids a check for a NULL kmem_cache_node pointer in new_slab() if the system is not compiled with NUMA support. [penberg@cs.helsinki.fi: fix oops and move ->nr_slabs into CONFIG_SLUB_DEBUG] Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2008-03-15ACPI: Remove ACPI_CUSTOM_DSDT_INITRD optionLinus Torvalds
This essentially reverts commit 71fc47a9adf8ee89e5c96a47222915c5485ac437 ("ACPI: basic initramfs DSDT override support"), because the code simply isn't ready. It did ugly things to the init sequence to populate the rootfs image early, but that just ended up showing other problems with the whole approach. The fact is, the VFS layer simply isn't initialized this early, and the relevant ACPI code should either run much later, or this shouldn't be done at all. For 2.6.25, we'll just pick the latter option. We can revisit this concept later if necessary. Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Tilman Schmidt <tilman@imap.cc> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Renninger <trenn@suse.de> Cc: Eric Piel <eric.piel@tremplin-utc.net> Cc: Len Brown <len.brown@intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Markus Gaugusch <dsdt@gaugusch.at> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-10rcu: move PREEMPT_RCU config option back under PREEMPTPaul E. McKenney
The original preemptible-RCU patch put the choice between classic and preemptible RCU into kernel/Kconfig.preempt, which resulted in build failures on machines not supporting CONFIG_PREEMPT. This choice was therefore moved to init/Kconfig, which worked, but placed the choice between classic and preemptible RCU at the top level, a very obtuse choice indeed. This patch changes from the Kconfig "choice" mechanism to a pair of booleans, only one of which (CONFIG_PREEMPT_RCU) is user-visible, and is located in kernel/Kconfig.preempt, where one would expect it to be. The other (CONFIG_CLASSIC_RCU) is in init/Kconfig so that it is available to all architectures, hopefully avoiding build breakage. Thanks to Roman Zippel for suggesting this approach. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: Josh Triplett <josh@freedesktop.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>