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2011-08-09lockdep: Fix wrong assumption in match_held_lockPeter Zijlstra
match_held_lock() was assuming it was being called on a lock class that had already seen usage. This condition was true for bug-free code using lockdep_assert_held(), since you're in fact holding the lock when calling it. However the assumption fails the moment you assume the assertion can fail, which is the whole point of having the assertion in the first place. Anyway, now that there's more lockdep_is_held() users, notably __rcu_dereference_check(), its much easier to trigger this since we test for a number of locks and we only need to hold any one of them to be good. Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1312547787.28695.2.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-05jump label: Reduce the cycle count by changing the link orderJason Baron
In the course of testing jump labels for use with the CFS bandwidth controller, Paul Turner, discovered that using jump labels reduced the branch count and the instruction count, but did not reduce the cycle count or wall time. I noticed that having the jump_label.o included in the kernel but not used in any way still caused this increase in cycle count and wall time. Thus, I moved jump_label.o in the kernel/Makefile, thus changing the link order, and presumably moving it out of hot icache areas. This brought down the cycle count/time as expected. In addition to Paul's testing, I've tested the patch using a single 'static_branch()' in the getppid() path, and basically running tight loops of calls to getppid(). Here are my results for the branch disabled case: With jump labels turned on (CONFIG_JUMP_LABEL), branch disabled: Performance counter stats for 'bash -c /tmp/getppid;true' (50 runs): 3,969,510,217 instructions # 0.864 IPC ( +-0.000% ) 4,592,334,954 cycles ( +- 0.046% ) 751,634,470 branches ( +- 0.000% ) 1.722635797 seconds time elapsed ( +- 0.046% ) Jump labels turned off (CONFIG_JUMP_LABEL not set), branch disabled: Performance counter stats for 'bash -c /tmp/getppid;true' (50 runs): 4,009,611,846 instructions # 0.867 IPC ( +-0.000% ) 4,622,210,580 cycles ( +- 0.012% ) 771,662,904 branches ( +- 0.000% ) 1.734341454 seconds time elapsed ( +- 0.022% ) Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: rth@redhat.com Cc: a.p.zijlstra@chello.nl Cc: rostedt@goodmis.org Link: http://lkml.kernel.org/r/20110805204040.GG2522@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Tested-by: Paul Turner <pjt@google.com>
2011-08-05Merge branch 'linus' into perf/urgentIngo Molnar
Merge reason: Include most of the merge window trees, to do fixes on top. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-05Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: slab, lockdep: Annotate the locks before using them lockdep: Clear whole lockdep_map on initialization slab, lockdep: Annotate slab -> rcu -> debug_object -> slab lockdep: Fix up warning lockdep: Fix trace_hardirqs_on_caller() futex: Fix regression with read only mappings
2011-08-04lockdep: Clear whole lockdep_map on initializationTejun Heo
lockdep_init_map() only initializes parts of lockdep_map and triggers kmemcheck warning when it is copied as a whole. There isn't anything to be gained by clearing selectively. memset() the whole structure and remove loop for ->class_cache[] clearing. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=35532 Signed-off-by: Tejun Heo <tj@kernel.org> Reported-and-tested-by: Christian Casteyde <casteyde.christian@free.fr> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=35532 Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110714131909.GJ3455@htj.dyndns.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-04lockdep: Fix up warningPeter Zijlstra
On Sun, 2011-07-24 at 21:06 -0400, Arnaud Lacombe wrote: > /src/linux/linux/kernel/lockdep.c: In function 'mark_held_locks': > /src/linux/linux/kernel/lockdep.c:2471:31: warning: comparison of > distinct pointer types lacks a cast The warning is harmless in this case, but the below makes it go away. Reported-by: Arnaud Lacombe <lacombar@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1311588599.2617.56.camel@laptop Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-04lockdep: Fix trace_hardirqs_on_caller()Peter Zijlstra
Commit dd4e5d3ac4a ("lockdep: Fix trace_[soft,hard]irqs_[on,off]() recursion") made a bit of a mess of the various checks and error conditions. In particular it moved the check for !irqs_disabled() before the spurious enable test, resulting in some warnings. Reported-by: Arnaud Lacombe <lacombar@gmail.com> Reported-by: Dave Jones <davej@redhat.com> Reported-and-tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1311679697.24752.28.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-04Boot up with usermodehelper disabledLinus Torvalds
The core device layer sends tons of uevent notifications for each device it finds, and if the kernel has been built with a non-empty CONFIG_UEVENT_HELPER_PATH that will make us try to execute the usermode helper binary for all these events very early in the boot. Not only won't the root filesystem even be mounted at that point, we literally won't have necessarily even initialized all the process handling data structures at that point, which causes no end of silly problems even when the usermode helper doesn't actually succeed in executing. So just use our existing infrastructure to disable the usermodehelpers to make the kernel start out with them disabled. We enable them when we've at least initialized stuff a bit. Problems related to an uninitialized init_ipc_ns.ids[IPC_SHM_IDS].rw_mutex reported by various people. Reported-by: Manuel Lauss <manuel.lauss@googlemail.com> Reported-by: Richard Weinberger <richard@nod.at> Reported-by: Marc Zyngier <maz@misterjones.org> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-04Merge branch 'linus' into core/urgentIngo Molnar
2011-08-04taskstats: add_del_listener() should ignore !valid listenersOleg Nesterov
When send_cpu_listeners() finds the orphaned listener it marks it as !valid and drops listeners->sem. Before it takes this sem for writing, s->pid can be reused and add_del_listener() can wrongly try to re-use this entry. Change add_del_listener() to check ->valid = T. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Vasiliy Kulikov <segoon@openwall.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-04taskstats: add_del_listener() shouldn't use the wrong nodeOleg Nesterov
1. Commit 26c4caea9d69 "don't allow duplicate entries in listener mode" changed add_del_listener(REGISTER) so that "next_cpu:" can reuse the listener allocated for the previous cpu, this doesn't look exactly right even if minor. Change the code to kfree() in the already-registered case, this case is unlikely anyway so the extra kmalloc_node() shouldn't hurt but looke more correct and clean. 2. use the plain list_for_each_entry() instead of _safe() to scan listeners->list. 3. Remove the unneeded INIT_LIST_HEAD(&s->list), we are going to list_add(&s->list). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Vasiliy Kulikov <segoon@openwall.com> Cc: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-01Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb: kdb,kgdb: Allow arbitrary kgdb magic knock sequences kdb: Remove all references to DOING_KGDB2 kdb,kgdb: Implement switch and pass buffer from kdb -> gdb kdb: cleanup unused variables missed in the original kdb merge
2011-08-01kdb,kgdb: Allow arbitrary kgdb magic knock sequencesJason Wessel
The first packet that gdb sends when the kernel is in kdb mode seems to change with every release of gdb. Instead of continuing to add many different gdb packets, change kdb to automatically look for any thing that looks like a gdb packet. Example 1 cold start test: echo g > /proc/sysrq-trigger $D#44+ Example 2 cold start test: echo g > /proc/sysrq-trigger $3#33 The second one should re-enter kdb's shell right away and is purely a test. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2011-08-01kdb: Remove all references to DOING_KGDB2Jason Wessel
The DOING_KGDB2 was originally a state variable for one of the two ways to automatically transition from kdb to kgdb. Purge all these variables and just use one single state for the transition. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2011-08-01kdb,kgdb: Implement switch and pass buffer from kdb -> gdbJason Wessel
When switching from kdb mode to kgdb mode packets were getting lost depending on the size of the fifo queue of the serial chip. When gdb initially connects if it is in kdb mode it should entirely send any character buffer over to the gdbstub when switching connections. Previously kdb was zero'ing out the character buffer and this could lead to gdb failing to connect at all, or a lengthy pause could occur on the initial connect. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2011-08-01kdb: cleanup unused variables missed in the original kdb mergeJason Wessel
The BTARGS and BTSYMARG variables do not have any function in the mainline version of kdb. Reported-by: Tim Bird <tim.bird@am.sony.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2011-08-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: m68k/math-emu: Remove unnecessary code m68k/math-emu: Remove commented out old code m68k: Kill warning in setup_arch() when compiling for Sun3 m68k/atari: Prefix GPIO_{IN,OUT} with CODEC_ sparc: iounmap() and *_free_coherent() - Use lookup_resource() m68k/atari: Reserve some ST-RAM early on for device buffer use m68k/amiga: Chip RAM - Use lookup_resource() resources: Add lookup_resource() sparc: _sparc_find_resource() should check for exact matches m68k/amiga: Chip RAM - Offset resource end by CHIP_PHYSADDR m68k/amiga: Chip RAM - Use resource_size() to fix off-by-one error m68k/amiga: Chip RAM - Change chipavail to an atomic_t m68k/amiga: Chip RAM - Always allocate from the start of memory m68k/amiga: Chip RAM - Convert from printk() to pr_*() m68k/amiga: Chip RAM - Use tabs for indentation
2011-07-30resources: Add lookup_resource()Geert Uytterhoeven
Add a function to find an existing resource by a resource start address. This allows to implement simple allocators (with a malloc/free-alike API) on top of the resource system. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2011-07-30Merge branch 'v4l_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (430 commits) [media] ir-mce_kbd-decoder: include module.h for its facilities [media] ov5642: include module.h for its facilities [media] em28xx: Fix DVB-C maxsize for em2884 [media] tda18271c2dd: Fix saw filter configuration for DVB-C @6MHz [media] v4l: mt9v032: Fix Bayer pattern [media] V4L: mt9m111: rewrite set_pixfmt [media] V4L: mt9m111: fix missing return value check mt9m111_reg_clear [media] V4L: initial driver for ov5642 CMOS sensor [media] V4L: sh_mobile_ceu_camera: fix Oops when USERPTR mapping fails [media] V4L: soc-camera: remove soc-camera bus and devices on it [media] V4L: soc-camera: un-export the soc-camera bus [media] V4L: sh_mobile_csi2: switch away from using the soc-camera bus notifier [media] V4L: add media bus configuration subdev operations [media] V4L: soc-camera: group struct field initialisations together [media] V4L: soc-camera: remove now unused soc-camera specific PM hooks [media] V4L: pxa-camera: switch to using standard PM hooks [media] NetUP Dual DVB-T/C CI RF: force card hardware revision by module param [media] Don't OOPS if videobuf_dvb_get_frontend return NULL [media] NetUP Dual DVB-T/C CI RF: load firmware according card revision [media] omap3isp: Support configurable HS/VS polarities ... Fix up conflicts: - arch/arm/mach-omap2/board-rx51-peripherals.c: cleanup regulator supply definitions in mach-omap2 vs OMAP3: RX-51: define vdds_csib regulator supply - drivers/staging/tm6000/tm6000-alsa.c (trivial)
2011-07-30Merge branch 'next/dt' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc * 'next/dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc: (21 commits) arm/dt: tegra devicetree support arm/versatile: Add device tree support dt/irq: add irq_domain_generate_simple() helper irq: add irq_domain translation infrastructure dmaengine: imx-sdma: add device tree probe support dmaengine: imx-sdma: sdma_get_firmware does not need to copy fw_name dmaengine: imx-sdma: use platform_device_id to identify sdma version mmc: sdhci-esdhc-imx: add device tree probe support mmc: sdhci-pltfm: dt device does not pass parent to sdhci_alloc_host mmc: sdhci-esdhc-imx: get rid of the uses of cpu_is_mx() mmc: sdhci-esdhc-imx: do not reference platform data after probe mmc: sdhci-esdhc-imx: extend card_detect and write_protect support for mx5 net/fec: add device tree probe support net: ibm_newemac: convert it to use of_get_phy_mode dt/net: add helper function of_get_phy_mode net/fec: gasket needs to be enabled for some i.mx serial/imx: add device tree probe support serial/imx: get rid of the uses of cpu_is_mx1() arm/dt: Add dtb make rule arm/dt: Add skeleton dtsi file ...
2011-07-28Merge branch 'imx/dt' into next/dtArnd Bergmann
2011-07-28irq: Track the owner of irq descriptorSebastian Andrzej Siewior
Interrupt descriptors can be allocated from modules. The interrupts are used by other modules, but we have no refcount on the module which provides the interrupts and there is no way to establish one on the device level as the interrupt using module is agnostic to the fact that the interrupt is provided by a module rather than by some builtin interrupt controller. To prevent removal of the interrupt providing module, we can track the owner of the interrupt descriptor, which also provides the relevant irq chip functions in the irq descriptor. request/setup_irq() can now acquire a refcount on the owner module to prevent unloading. free_irq() drops the refcount. Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Link: http://lkml.kernel.org/r/20110711101731.GA13804@Chamillionaire.breakpoint.cc Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-07-28irq: Always set IRQF_ONESHOT if no primary handler is specifiedSebastian Andrzej Siewior
If no primary handler is specified then a default one is assigned which always returns IRQ_WAKE_THREAD. This handler requires the IRQF_ONESHOT flag on LEVEL / EIO typed irqs because the source of interrupt is not disabled. Since it is required for those users and there is no difference for others it makes sense to add this flag unconditionally. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/1310070737-18514-1-git-send-email-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-07-28dt/irq: add irq_domain_generate_simple() helperGrant Likely
irq_domain_generate_simple() is an easy way to generate an irq translation domain for simple irq controllers. It assumes a flat 1:1 mapping from hardware irq number to an offset of the first linux irq number assigned to the controller Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-28irq: add irq_domain translation infrastructureGrant Likely
This patch adds irq_domain infrastructure for translating from hardware irq numbers to linux irqs. This is particularly important for architectures adding device tree support because the current implementation (excluding PowerPC and SPARC) cannot handle translation for more than a single interrupt controller. irq_domain supports device tree translation for any number of interrupt controllers. This patch converts x86, Microblaze, ARM and MIPS to use irq_domain for device tree irq translation. x86 is untested beyond compiling it, irq_domain is enabled for MIPS and Microblaze, but the old behaviour is preserved until the core code is modified to actually register an irq_domain yet. On ARM it works and is required for much of the new ARM device tree board support. PowerPC has /not/ been converted to use this new infrastructure. It is still missing some features before it can replace the virq infrastructure already in powerpc (see documentation on irq_domain_map/unmap for details). Followup patches will add the missing pieces and migrate PowerPC to use irq_domain. SPARC has its own method of managing interrupts from the device tree and is unaffected by this change. Acked-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-28Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (54 commits) tpm_nsc: Fix bug when loading multiple TPM drivers tpm: Move tpm_tis_reenable_interrupts out of CONFIG_PNP block tpm: Fix compilation warning when CONFIG_PNP is not defined TOMOYO: Update kernel-doc. tpm: Fix a typo tpm_tis: Probing function for Intel iTPM bug tpm_tis: Fix the probing for interrupts tpm_tis: Delay ACPI S3 suspend while the TPM is busy tpm_tis: Re-enable interrupts upon (S3) resume tpm: Fix display of data in pubek sysfs entry tpm_tis: Add timeouts sysfs entry tpm: Adjust interface timeouts if they are too small tpm: Use interface timeouts returned from the TPM tpm_tis: Introduce durations sysfs entry tpm: Adjust the durations if they are too small tpm: Use durations returned from TPM TOMOYO: Enable conditional ACL. TOMOYO: Allow using argv[]/envp[] of execve() as conditions. TOMOYO: Allow using executable's realpath and symlink's target as conditions. TOMOYO: Allow using owner/group etc. of file objects as conditions. ... Fix up trivial conflict in security/tomoyo/realpath.c
2011-07-27[media] v4l2-compat-ioctl32: add VIDIOC_DQEVENT supportHans Verkuil
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27signals: sys_ssetmask/sys_rt_sigsuspend should use set_current_blocked()Oleg Nesterov
sys_ssetmask(), sys_rt_sigsuspend() and compat_sys_rt_sigsuspend() change ->blocked directly. This is not correct, see the changelog in e6fa16ab "signal: sigprocmask() should do retarget_shared_pending()" Change them to use set_current_blocked(). Another change is that now we are doing ->saved_sigmask = ->blocked lockless, it doesn't make any sense to do this under ->siglock. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Matt Fleming <matt.fleming@linux.intel.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26atomic: use <linux/atomic.h>Arun Sharma
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26panic: panic=-1 for immediate rebootHugh Dickins
When a kernel BUG or oops occurs, ChromeOS intends to panic and immediately reboot, with stacktrace and other messages preserved in RAM across reboot. But the longer we delay, the more likely the user is to poweroff and lose the info. panic_timeout (seconds before rebooting) is set by panic= boot option or sysctl or /proc/sys/kernel/panic; but 0 means wait forever, so at present we have to delay at least 1 second. Let a negative number mean reboot immediately (with the small cosmetic benefit of suppressing that newline-less "Rebooting in %d seconds.." message). Signed-off-by: Hugh Dickins <hughd@chromium.org> Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Olaf Hering <olaf@aepfle.de> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Dave Airlie <airlied@gmail.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26gcov: disable CONSTRUCTORS for UMLVitaliy Ivanov
Selecting GCOV for UML causing configuration mismatch: warning: (GCOV_KERNEL) selects CONSTRUCTORS which has unmet direct dependencies (!UML) Constructors are not needed for UML. Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Acked-by: Richard Weinberger <richard@nod.at> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26ipc: introduce shm_rmid_forced sysctlVasiliy Kulikov
Add support for the shm_rmid_forced sysctl. If set to 1, all shared memory objects in current ipc namespace will be automatically forced to use IPC_RMID. The POSIX way of handling shmem allows one to create shm objects and call shmdt(), leaving shm object associated with no process, thus consuming memory not counted via rlimits. With shm_rmid_forced=1 the shared memory object is counted at least for one process, so OOM killer may effectively kill the fat process holding the shared memory. It obviously breaks POSIX - some programs relying on the feature would stop working. So set shm_rmid_forced=1 only if you're sure nobody uses "orphaned" memory. Use shm_rmid_forced=0 by default for compatability reasons. The feature was previously impemented in -ow as a configure option. [akpm@linux-foundation.org: fix documentation, per Randy] [akpm@linux-foundation.org: fix warning] [akpm@linux-foundation.org: readability/conventionality tweaks] [akpm@linux-foundation.org: fix shm_rmid_forced/shm_forced_rmid confusion, use standard comment layout] Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "Serge E. Hallyn" <serge.hallyn@canonical.com> Cc: Daniel Lezcano <daniel.lezcano@free.fr> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Solar Designer <solar@openwall.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26kernel/fork.c: fix a few coding style issuesDaniel Rebelo de Oliveira
Signed-off-by: Daniel Rebelo de Oliveira <psykon@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26cpusets: randomize node rotor used in cpuset_mem_spread_node()Michal Hocko
[ This patch has already been accepted as commit 0ac0c0d0f837 but later reverted (commit 35926ff5fba8) because it itroduced arch specific __node_random which was defined only for x86 code so it broke other archs. This is a followup without any arch specific code. Other than that there are no functional changes.] Some workloads that create a large number of small files tend to assign too many pages to node 0 (multi-node systems). Part of the reason is that the rotor (in cpuset_mem_spread_node()) used to assign nodes starts at node 0 for newly created tasks. This patch changes the rotor to be initialized to a random node number of the cpuset. [akpm@linux-foundation.org: fix layout] [Lee.Schermerhorn@hp.com: Define stub numa_random() for !NUMA configuration] [mhocko@suse.cz: Make it arch independent] [akpm@linux-foundation.org: fix CONFIG_NUMA=y, MAX_NUMNODES>1 build] Signed-off-by: Jack Steiner <steiner@sgi.com> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Paul Menage <menage@google.com> Cc: Jack Steiner <steiner@sgi.com> Cc: Robin Holt <holt@sgi.com> Cc: David Rientjes <rientjes@google.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: David Rientjes <rientjes@google.com> Cc: Jack Steiner <steiner@sgi.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Paul Menage <menage@google.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Robin Holt <holt@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26futex: Fix regression with read only mappingsShawn Bohrer
commit 7485d0d3758e8e6491a5c9468114e74dc050785d (futexes: Remove rw parameter from get_futex_key()) in 2.6.33 fixed two problems: First, It prevented a loop when encountering a ZERO_PAGE. Second, it fixed RW MAP_PRIVATE futex operations by forcing the COW to occur by unconditionally performing a write access get_user_pages_fast() to get the page. The commit also introduced a user-mode regression in that it broke futex operations on read-only memory maps. For example, this breaks workloads that have one or more reader processes doing a FUTEX_WAIT on a futex within a read only shared file mapping, and a writer processes that has a writable mapping issuing the FUTEX_WAKE. This fixes the regression for valid futex operations on RO mappings by trying a RO get_user_pages_fast() when the RW get_user_pages_fast() fails. This change makes it necessary to also check for invalid use cases, such as anonymous RO mappings (which can never change) and the ZERO_PAGE which the commit referenced above was written to address. This patch does restore the original behavior with RO MAP_PRIVATE mappings, which have inherent user-mode usage problems and don't really make sense. With this patch performing a FUTEX_WAIT within a RO MAP_PRIVATE mapping will be successfully woken provided another process updates the region of the underlying mapped file. However, the mmap() man page states that for a MAP_PRIVATE mapping: It is unspecified whether changes made to the file after the mmap() call are visible in the mapped region. So user-mode users attempting to use futex operations on RO MAP_PRIVATE mappings are depending on unspecified behavior. Additionally a RO MAP_PRIVATE mapping could fail to wake up in the following case. Thread-A: call futex(FUTEX_WAIT, memory-region-A). get_futex_key() return inode based key. sleep on the key Thread-B: call mprotect(PROT_READ|PROT_WRITE, memory-region-A) Thread-B: write memory-region-A. COW happen. This process's memory-region-A become related to new COWed private (ie PageAnon=1) page. Thread-B: call futex(FUETX_WAKE, memory-region-A). get_futex_key() return mm based key. IOW, we fail to wake up Thread-A. Once again doing something like this is just silly and users who do something like this get what they deserve. While RO MAP_PRIVATE mappings are nonsensical, checking for a private mapping requires walking the vmas and was deemed too costly to avoid a userspace hang. This Patch is based on Peter Zijlstra's initial patch with modifications to only allow RO mappings for futex operations that need VERIFY_READ access. Reported-by: David Oliver <david@rgmadvisors.com> Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: peterz@infradead.org Cc: eric.dumazet@gmail.com Cc: zvonler@rgmadvisors.com Cc: hughd@google.com Link: http://lkml.kernel.org/r/1309450892-30676-1-git-send-email-sbohrer@rgmadvisors.com Cc: stable@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-07-26genirq: Fix wrong bit operationjhbird.choi@samsung.com
(!msk & 0x01) should be !(msk & 0x01) Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com> Link: http://lkml.kernel.org/r/1311229754-6003-1-git-send-email-jhbird.choi@samsung.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@kernel.org
2011-07-26Merge 'akpm' patch seriesLinus Torvalds
* Merge akpm patch series: (122 commits) drivers/connector/cn_proc.c: remove unused local Documentation/SubmitChecklist: add RCU debug config options reiserfs: use hweight_long() reiserfs: use proper little-endian bitops pnpacpi: register disabled resources drivers/rtc/rtc-tegra.c: properly initialize spinlock drivers/rtc/rtc-twl.c: check return value of twl_rtc_write_u8() in twl_rtc_set_time() drivers/rtc: add support for Qualcomm PMIC8xxx RTC drivers/rtc/rtc-s3c.c: support clock gating drivers/rtc/rtc-mpc5121.c: add support for RTC on MPC5200 init: skip calibration delay if previously done misc/eeprom: add eeprom access driver for digsy_mtc board misc/eeprom: add driver for microwire 93xx46 EEPROMs checkpatch.pl: update $logFunctions checkpatch: make utf-8 test --strict checkpatch.pl: add ability to ignore various messages checkpatch: add a "prefer __aligned" check checkpatch: validate signature styles and To: and Cc: lines checkpatch: add __rcu as a sparse modifier checkpatch: suggest using min_t or max_t ... Did this as a merge because of (trivial) conflicts in - Documentation/feature-removal-schedule.txt - arch/xtensa/include/asm/uaccess.h that were just easier to fix up in the merge than in the patch series.
2011-07-26kernel/configs.c: include MODULE_*() when CONFIG_IKCONFIG_PROC=nStephen Boyd
If CONFIG_IKCONFIG=m but CONFIG_IKCONFIG_PROC=n we get a module that has no MODULE_LICENSE definition. Move the MODULE_*() definitions outside the CONFIG_IKCONFIG_PROC #ifdef to prevent this configuration from tainting the kernel. Signed-off-by: Stephen Boyd <bebarino@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26notifiers: sys: move reboot notifiers into reboot.hAmerigo Wang
It is not necessary to share the same notifier.h. This patch already moves register_reboot_notifier() and unregister_reboot_notifier() from kernel/notifier.c to kernel/sys.c. [amwang@redhat.com: make allyesconfig succeed on ppc64] Signed-off-by: WANG Cong <amwang@redhat.com> Cc: David Miller <davem@davemloft.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Greg KH <greg@kroah.com> Signed-off-by: WANG Cong <amwang@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26devres: fix possible use after freeMaxin B John
devres uses the pointer value as key after it's freed, which is safe but triggers spurious use-after-free warnings on some static analysis tools. Rearrange code to avoid such warnings. Signed-off-by: Maxin B. John <maxin.john@gmail.com> Reviewed-by: Rolf Eike Beer <eike-kernel@sf-tec.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26mm/futex: fix futex writes on archs with SW tracking of dirty & youngBenjamin Herrenschmidt
I haven't reproduced it myself but the fail scenario is that on such machines (notably ARM and some embedded powerpc), if you manage to hit that futex path on a writable page whose dirty bit has gone from the PTE, you'll livelock inside the kernel from what I can tell. It will go in a loop of trying the atomic access, failing, trying gup to "fix it up", getting succcess from gup, go back to the atomic access, failing again because dirty wasn't fixed etc... So I think you essentially hang in the kernel. The scenario is probably rare'ish because affected architecture are embedded and tend to not swap much (if at all) so we probably rarely hit the case where dirty is missing or young is missing, but I think Shan has a piece of SW that can reliably reproduce it using a shared writable mapping & fork or something like that. On archs who use SW tracking of dirty & young, a page without dirty is effectively mapped read-only and a page without young unaccessible in the PTE. Additionally, some architectures might lazily flush the TLB when relaxing write protection (by doing only a local flush), and expect a fault to invalidate the stale entry if it's still present on another processor. The futex code assumes that if the "in_atomic()" access -EFAULT's, it can "fix it up" by causing get_user_pages() which would then be equivalent to taking the fault. However that isn't the case. get_user_pages() will not call handle_mm_fault() in the case where the PTE seems to have the right permissions, regardless of the dirty and young state. It will eventually update those bits ... in the struct page, but not in the PTE. Additionally, it will not handle the lazy TLB flushing that can be required by some architectures in the fault case. Basically, gup is the wrong interface for the job. The patch provides a more appropriate one which boils down to just calling handle_mm_fault() since what we are trying to do is simulate a real page fault. The futex code currently attempts to write to user memory within a pagefault disabled section, and if that fails, tries to fix it up using get_user_pages(). This doesn't work on archs where the dirty and young bits are maintained by software, since they will gate access permission in the TLB, and will not be updated by gup(). In addition, there's an expectation on some archs that a spurious write fault triggers a local TLB flush, and that is missing from the picture as well. I decided that adding those "features" to gup() would be too much for this already too complex function, and instead added a new simpler fixup_user_fault() which is essentially a wrapper around handle_mm_fault() which the futex code can call. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix some nits Darren saw, fiddle comment layout] Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reported-by: Shan Hai <haishan.bai@gmail.com> Tested-by: Shan Hai <haishan.bai@gmail.com> Cc: David Laight <David.Laight@ACULAB.COM> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Darren Hart <darren.hart@intel.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26Merge branches 'kbuild', 'packaging' and 'misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: genksyms: Use same type in loop comparison kbuild: silence generated makefile message kernel: prevent unnecessary rebuilding due to config_data.gz headers_install: fix __packed in exported kernel headers dtc: regen parser dtc: migrate parser to implicit rules kconfig: regen parser kconfig: migrate parser to implicit rules kconfig/zconf.l: do not ask to generate backup kconfig: kill no longer needed reference to YYDEBUG kconfig: constify `kconf_id_lookup' genksym: regen parser genksyms: migrate parser to implicit rules genksyms: drop -Wno-uninitialized from HOSTCFLAGS_parse.tab.o genksyms: pass hash and lookup functions name and target language though the input file kbuild: simplify the %_shipped rule kbuild: add implicit rules for parser generation kbuild: add `baseprereq' kbuild: Fix reference to vermagic.h * 'packaging' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: package: Makefile: fix perf target bug * 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: gitignore: ignore debian build directory
2011-07-25Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits) fs: Merge split strings treewide: fix potentially dangerous trailing ';' in #defined values/expressions uwb: Fix misspelling of neighbourhood in comment net, netfilter: Remove redundant goto in ebt_ulog_packet trivial: don't touch files that are removed in the staging tree lib/vsprintf: replace link to Draft by final RFC number doc: Kconfig: `to be' -> `be' doc: Kconfig: Typo: square -> squared doc: Konfig: Documentation/power/{pm => apm-acpi}.txt drivers/net: static should be at beginning of declaration drivers/media: static should be at beginning of declaration drivers/i2c: static should be at beginning of declaration XTENSA: static should be at beginning of declaration SH: static should be at beginning of declaration MIPS: static should be at beginning of declaration ARM: static should be at beginning of declaration rcu: treewide: Do not use rcu_read_lock_held when calling rcu_dereference_check Update my e-mail address PCIe ASPM: forcedly -> forcibly gma500: push through device driver tree ... Fix up trivial conflicts: - arch/arm/mach-ep93xx/dma-m2p.c (deleted) - drivers/gpio/gpio-ep93xx.c (renamed and context nearby) - drivers/net/r8169.c (just context changes)
2011-07-25Merge branch 'for-3.1/core' of git://git.kernel.dk/linux-blockLinus Torvalds
* 'for-3.1/core' of git://git.kernel.dk/linux-block: (24 commits) block: strict rq_affinity backing-dev: use synchronize_rcu_expedited instead of synchronize_rcu block: fix patch import error in max_discard_sectors check block: reorder request_queue to remove 64 bit alignment padding CFQ: add think time check for group CFQ: add think time check for service tree CFQ: move think time check variables to a separate struct fixlet: Remove fs_excl from struct task. cfq: Remove special treatment for metadata rqs. block: document blk_plug list access block: avoid building too big plug list compat_ioctl: fix make headers_check regression block: eliminate potential for infinite loop in blkdev_issue_discard compat_ioctl: fix warning caused by qemu block: flush MEDIA_CHANGE from drivers on close(2) blk-throttle: Make total_nr_queued unsigned block: Add __attribute__((format(printf...) and fix fallout fs/partitions/check.c: make local symbols static block:remove some spare spaces in genhd.c block:fix the comment error in blkdev.h ...
2011-07-25trace events: Update version number reference to new 3.x scheme for ↵Jesper Juhl
EVENT_POWER_TRACING_DEPRECATED What was scheduled to be 2.6.41 is now going to be 3.1 . Signed-off-by: Jesper Juhl <jj@chaosbits.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1107250929370.8080@swampdragon.chaosbits.net Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linusLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: modpost: Fix modpost's license checking V3 module: add /sys/module/<name>/uevent files module: change attr callbacks to take struct module_kobject modules: make arch's use default loader hooks modules: add default loader hook implementations param: fix return value handling in param_set_*
2011-07-24Merge branch 'kvm-updates/3.1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
* 'kvm-updates/3.1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (143 commits) KVM: IOMMU: Disable device assignment without interrupt remapping KVM: MMU: trace mmio page fault KVM: MMU: mmio page fault support KVM: MMU: reorganize struct kvm_shadow_walk_iterator KVM: MMU: lockless walking shadow page table KVM: MMU: do not need atomicly to set/clear spte KVM: MMU: introduce the rules to modify shadow page table KVM: MMU: abstract some functions to handle fault pfn KVM: MMU: filter out the mmio pfn from the fault pfn KVM: MMU: remove bypass_guest_pf KVM: MMU: split kvm_mmu_free_page KVM: MMU: count used shadow pages on prepareing path KVM: MMU: rename 'pt_write' to 'emulate' KVM: MMU: cleanup for FNAME(fetch) KVM: MMU: optimize to handle dirty bit KVM: MMU: cache mmio info on page fault path KVM: x86: introduce vcpu_mmio_gva_to_gpa to cleanup the code KVM: MMU: do not update slot bitmap if spte is nonpresent KVM: MMU: fix walking shadow page table KVM guest: KVM Steal time registration ...
2011-07-24module: add /sys/module/<name>/uevent filesKay Sievers
Userspace wants to manage module parameters with udev rules. This currently only works for loaded modules, but not for built-in ones. To allow access to the built-in modules we need to re-trigger all module load events that happened before any userspace was running. We already do the same thing for all devices, subsystems(buses) and drivers. This adds the currently missing /sys/module/<name>/uevent files to all module entries. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (split & trivial fix)
2011-07-24module: change attr callbacks to take struct module_kobjectKay Sievers
This simplifies the next patch, where we have an attribute on a builtin module (ie. module == NULL). Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (split into 2)
2011-07-24modules: add default loader hook implementationsJonas Bonn
The module loader code allows architectures to hook into the code by providing a small number of entry points that each arch must implement. This patch provides __weakly linked generic implementations of these entry points for architectures that don't need to do anything special. Signed-off-by: Jonas Bonn <jonas@southpole.se> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>