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2013-03-26rcu: Provide compile-time control for no-CBs CPUsPaul E. McKenney
Currently, the only way to specify no-CBs CPUs is via the rcu_nocbs kernel command-line parameter. This is inconvenient in some cases, particularly for randconfig testing, so this commit adds a new set of kernel configuration parameters. CONFIG_RCU_NOCB_CPU_NONE (the default) retains the old behavior, CONFIG_RCU_NOCB_CPU_ZERO offloads callback processing from CPU 0 (along with any other CPUs specified by the rcu_nocbs boot-time parameter), and CONFIG_RCU_NOCB_CPU_ALL offloads callback processing from all CPUs. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-03-12rcu: Remove restrictions on no-CBs CPUsPaul E. McKenney
Currently, CPU 0 is constrained to not be a no-CBs CPU, and furthermore at least one no-CBs CPU must remain online at any given time. These restrictions are problematic in some situations, such as cases where all CPUs must run a real-time workload that needs to be insulated from OS jitter and latencies due to RCU callback invocation. This commit therefore provides no-CBs CPUs a (very crude and energy-inefficient) way to start and to wait for grace periods independently of the normal RCU callback mechanisms. This approach allows any or all of the CPUs to be designated as no-CBs CPUs, and allows any proper subset of the CPUs (whether no-CBs CPUs or not) to be offlined. This commit also provides a fix for a locking bug spotted by Xie ChanglongX <changlongx.xie@intel.com>. Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-03-02Merge tag 'arc-v3.9-rc1-late' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc Pull new ARC architecture from Vineet Gupta: "Initial ARC Linux port with some fixes on top for 3.9-rc1: I would like to introduce the Linux port to ARC Processors (from Synopsys) for 3.9-rc1. The patch-set has been discussed on the public lists since Nov and has received a fair bit of review, specially from Arnd, tglx, Al and other subsystem maintainers for DeviceTree, kgdb... The arch bits are in arch/arc, some asm-generic changes (acked by Arnd), a minor change to PARISC (acked by Helge). The series is a touch bigger for a new port for 2 main reasons: 1. It enables a basic kernel in first sub-series and adds ptrace/kgdb/.. later 2. Some of the fallout of review (DeviceTree support, multi-platform- image support) were added on top of orig series, primarily to record the revision history. This updated pull request additionally contains - fixes due to our GNU tools catching up with the new syscall/ptrace ABI - some (minor) cross-arch Kconfig updates." * tag 'arc-v3.9-rc1-late' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (82 commits) ARC: split elf.h into uapi and export it for userspace ARC: Fixup the current ABI version ARC: gdbserver using regset interface possibly broken ARC: Kconfig cleanup tracking cross-arch Kconfig pruning in merge window ARC: make a copy of flat DT ARC: [plat-arcfpga] DT arc-uart bindings change: "baud" => "current-speed" ARC: Ensure CONFIG_VIRT_TO_BUS is not enabled ARC: Fix pt_orig_r8 access ARC: [3.9] Fallout of hlist iterator update ARC: 64bit RTSC timestamp hardware issue ARC: Don't fiddle with non-existent caches ARC: Add self to MAINTAINERS ARC: Provide a default serial.h for uart drivers needing BASE_BAUD ARC: [plat-arcfpga] defconfig for fully loaded ARC Linux ARC: [Review] Multi-platform image #8: platform registers SMP callbacks ARC: [Review] Multi-platform image #7: SMP common code to use callbacks ARC: [Review] Multi-platform image #6: cpu-to-dma-addr optional ARC: [Review] Multi-platform image #5: NR_IRQS defined by ARC core ARC: [Review] Multi-platform image #4: Isolate platform headers ARC: [Review] Multi-platform image #3: switch to board callback ...
2013-02-25Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace and namespace infrastructure changes from Eric W Biederman: "This set of changes starts with a few small enhnacements to the user namespace. reboot support, allowing more arbitrary mappings, and support for mounting devpts, ramfs, tmpfs, and mqueuefs as just the user namespace root. I do my best to document that if you care about limiting your unprivileged users that when you have the user namespace support enabled you will need to enable memory control groups. There is a minor bug fix to prevent overflowing the stack if someone creates way too many user namespaces. The bulk of the changes are a continuation of the kuid/kgid push down work through the filesystems. These changes make using uids and gids typesafe which ensures that these filesystems are safe to use when multiple user namespaces are in use. The filesystems converted for 3.9 are ceph, 9p, afs, ocfs2, gfs2, ncpfs, nfs, nfsd, and cifs. The changes for these filesystems were a little more involved so I split the changes into smaller hopefully obviously correct changes. XFS is the only filesystem that remains. I was hoping I could get that in this release so that user namespace support would be enabled with an allyesconfig or an allmodconfig but it looks like the xfs changes need another couple of days before it they are ready." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (93 commits) cifs: Enable building with user namespaces enabled. cifs: Convert struct cifs_ses to use a kuid_t and a kgid_t cifs: Convert struct cifs_sb_info to use kuids and kgids cifs: Modify struct smb_vol to use kuids and kgids cifs: Convert struct cifsFileInfo to use a kuid cifs: Convert struct cifs_fattr to use kuid and kgids cifs: Convert struct tcon_link to use a kuid. cifs: Modify struct cifs_unix_set_info_args to hold a kuid_t and a kgid_t cifs: Convert from a kuid before printing current_fsuid cifs: Use kuids and kgids SID to uid/gid mapping cifs: Pass GLOBAL_ROOT_UID and GLOBAL_ROOT_GID to keyring_alloc cifs: Use BUILD_BUG_ON to validate uids and gids are the same size cifs: Override unmappable incoming uids and gids nfsd: Enable building with user namespaces enabled. nfsd: Properly compare and initialize kuids and kgids nfsd: Store ex_anon_uid and ex_anon_gid as kuids and kgids nfsd: Modify nfsd4_cb_sec to use kuids and kgids nfsd: Handle kuids and kgids in the nfs4acl to posix_acl conversion nfsd: Convert nfsxdr to use kuids and kgids nfsd: Convert nfs3xdr to use kuids and kgids ...
2013-02-25Merge tag 'modules-next-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module update from Rusty Russell: "The sweeping change is to make add_taint() explicitly indicate whether to disable lockdep, but it's a mechanical change." * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: MODSIGN: Add option to not sign modules during modules_install MODSIGN: Add -s <signature> option to sign-file MODSIGN: Specify the hash algorithm on sign-file command line MODSIGN: Simplify Makefile with a Kconfig helper module: clean up load_module a little more. modpost: Ignore ARC specific non-alloc sections module: constify within_module_* taint: add explicit flag to show whether lock dep is still OK. module: printk message when module signature fail taints kernel.
2013-02-21Merge tag 'please-pull-misc-3.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux Pull misc ia64 bits from Tony Luck. * tag 'please-pull-misc-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux: MAINTAINERS: update SGI & ia64 Altix stuff sysctl: Enable IA64 "ignore-unaligned-usertrap" to be used cross-arch
2013-02-21Merge tag 'driver-core-3.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core patches from Greg Kroah-Hartman: "Here is the big driver core merge for 3.9-rc1 There are two major series here, both of which touch lots of drivers all over the kernel, and will cause you some merge conflicts: - add a new function called devm_ioremap_resource() to properly be able to check return values. - remove CONFIG_EXPERIMENTAL Other than those patches, there's not much here, some minor fixes and updates" Fix up trivial conflicts * tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (221 commits) base: memory: fix soft/hard_offline_page permissions drivercore: Fix ordering between deferred_probe and exiting initcalls backlight: fix class_find_device() arguments TTY: mark tty_get_device call with the proper const values driver-core: constify data for class_find_device() firmware: Ignore abort check when no user-helper is used firmware: Reduce ifdef CONFIG_FW_LOADER_USER_HELPER firmware: Make user-mode helper optional firmware: Refactoring for splitting user-mode helper code Driver core: treat unregistered bus_types as having no devices watchdog: Convert to devm_ioremap_resource() thermal: Convert to devm_ioremap_resource() spi: Convert to devm_ioremap_resource() power: Convert to devm_ioremap_resource() mtd: Convert to devm_ioremap_resource() mmc: Convert to devm_ioremap_resource() mfd: Convert to devm_ioremap_resource() media: Convert to devm_ioremap_resource() iommu: Convert to devm_ioremap_resource() drm: Convert to devm_ioremap_resource() ...
2013-02-19Merge branch 'for-3.9-async' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull async changes from Tejun Heo: "These are followups for the earlier deadlock issue involving async ending up waiting for itself through block requesting module[1]. The following changes are made by these commits. - Instead of requesting default elevator on each request_queue init, block now requests it once early during boot. - Kmod triggers warning if invoked from an async worker. - Async synchronization implementation has been reimplemented. It's a lot simpler now." * 'for-3.9-async' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: async: initialise list heads to fix crash async: replace list of active domains with global list of pending items async: keep pending tasks on async_domain and remove async_pending async: use ULLONG_MAX for infinity cookie value async: bring sanity to the use of words domain and running async, kmod: warn on synchronous request_module() from async workers block: don't request module during elevator init init, block: try to load default elevator module early during boot
2013-02-19Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "Main changes: - scheduler side full-dynticks (user-space execution is undisturbed and receives no timer IRQs) preparation changes that convert the cputime accounting code to be full-dynticks ready, from Frederic Weisbecker. - Initial sched.h split-up changes, by Clark Williams - select_idle_sibling() performance improvement by Mike Galbraith: " 1 tbench pair (worst case) in a 10 core + SMT package: pre 15.22 MB/sec 1 procs post 252.01 MB/sec 1 procs " - sched_rr_get_interval() ABI fix/change. We think this detail is not used by apps (so it's not an ABI in practice), but lets keep it under observation. - misc RT scheduling cleanups, optimizations" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) sched/rt: Add <linux/sched/rt.h> header to <linux/init_task.h> cputime: Remove irqsave from seqlock readers sched, powerpc: Fix sched.h split-up build failure cputime: Restore CPU_ACCOUNTING config defaults for PPC64 sched/rt: Move rt specific bits into new header file sched/rt: Add a tuning knob to allow changing SCHED_RR timeslice sched: Move sched.h sysctl bits into separate header sched: Fix signedness bug in yield_to() sched: Fix select_idle_sibling() bouncing cow syndrome sched/rt: Further simplify pick_rt_task() sched/rt: Do not account zero delta_exec in update_curr_rt() cputime: Safely read cputime of full dynticks CPUs kvm: Prepare to add generic guest entry/exit callbacks cputime: Use accessors to read task cputime stats cputime: Allow dynamic switch between tick/virtual based cputime accounting cputime: Generic on-demand virtual cputime accounting cputime: Move default nsecs_to_cputime() to jiffies based cputime file cputime: Librarize per nsecs resolution cputime definitions cputime: Avoid multiplication overflow on utime scaling context_tracking: Export context state for generic vtime ... Fix up conflict in kernel/context_tracking.c due to comment additions.
2013-02-19Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq core changes from Ingo Molnar: "The biggest changes are the IRQ-work and printk changes from Frederic Weisbecker, which prepare the code for 'full dynticks' (the ability to stop or slow down the periodic tick arbitrarily, not just in idle time as today): - Don't stop tick with irq works pending. This fix is generally useful and concerns archs that can't raise self IPIs. - Flush irq works before CPU offlining. - Introduce "lazy" irq works that can wait for the next tick to be executed, unless it's stopped. - Implement klogd wake up using irq work. This removes the ad-hoc printk_tick()/printk_needs_cpu() hooks and make it working even in dynticks mode. - Cleanups and fixes." * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Export enable/disable_percpu_irq() arch Kconfig: Remove references to IRQ_PER_CPU irq_work: Remove return value from the irq_work_queue() function genirq: Avoid deadlock in spurious handling printk: Wake up klogd using irq_work irq_work: Make self-IPIs optable irq_work: Warn if there's still work on cpu_down irq_work: Flush work on CPU_DYING irq_work: Don't stop the tick with pending works nohz: Add API to check tick state irq_work: Remove CONFIG_HAVE_IRQ_WORK irq_work: Fix racy check on work pending flag irq_work: Fix racy IRQ_WORK_BUSY flag setting
2013-02-15sysctl: Enable PARISC "unaligned-trap" to be used cross-archVineet Gupta
PARISC defines /proc/sys/kernel/unaligned-trap to runtime toggle unaligned access emulation. The exact mechanics of enablig/disabling are still arch specific, we can make the sysctl usable by other arches. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Helge Deller <deller@gmx.de> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Serge Hallyn <serge.hallyn@canonical.com>
2013-02-13cifs: Enable building with user namespaces enabled.Eric W. Biederman
Cc: Steve French <smfrench@gmail.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13nfsd: Enable building with user namespaces enabled.Eric W. Biederman
Now that the kuids and kgids conversion have propogated through net/sunrpc/ and the fs/nfsd/ it is safe to enable building nfsd when user namespaces are enabled. Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13nfs: Enable building with user namespaces enabled.Eric W. Biederman
Now that the kuids and kgids conversion have propogated through net/sunrpc/ and the fs/nfs/ it is safe to enable building nfs when user namespaces are enabled. Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13ncpfs: Support interacting with multiple user namespacesEric W. Biederman
ncpfs does not natively support uids and gids so this conversion was simply a matter of updating the the type of the mounteduid, the uid and the gid on the superblock. Fixing the ioctls that read them, updating the mount option parser and the mount option printer. Cc: Petr Vandrovec <petr@vandrovec.name> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2013-02-13gfs2: Enable building with user namespaces enabledEric W. Biederman
Now that all of the necessary work has been done to push kuids and kgids throughout gfs2 and to convert between kuids and kgids when reading and writing the on disk structures it is safe to enable gfs2 when multiple user namespaces are enabled. Cc: Steven Whitehouse <swhiteho@redhat.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13ocfs2: Enable building with user namespaces enabledEric W. Biederman
Now that ocfs2 has been converted to store uids and gids in kuid_t and kgid_t and all of the conversions have been added to the appropriate places it is safe to allow building and using ocfs2 with user namespace support enabled. Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13coda: Allow coda to be built when user namespace support is enabledEric W. Biederman
Now that the coda kernel to userspace has been modified to convert between kuids and kgids and uids and gids, and all internal coda structures have be modified to store uids and gids as kuids and kgids it is safe to allow code to be built with user namespace support enabled. Cc: Jan Harkes <jaharkes@cs.cmu.edu> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13afs: Support interacting with multiple user namespacesEric W. Biederman
Modify struct afs_file_status to store owner as a kuid_t and group as a kgid_t. In xdr_decode_AFSFetchStatus as owner is now a kuid_t and group is now a kgid_t don't use the EXTRACT macro. Instead perform the work of the extract macro explicitly. Read the value with ntohl and convert it to the appropriate type with make_kuid or make_kgid. Test if the value is different from what is stored in status and update changed. Update the value in status. In xdr_encode_AFS_StoreStatus call from_kuid or from_kgid as we are computing the on the wire encoding. Initialize uids with GLOBAL_ROOT_UID instead of 0. Initialize gids with GLOBAL_ROOT_GID instead of 0. Cc: David Howells <dhowells@redhat.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2013-02-129p: Allow building 9p with user namespaces enabled.Eric W. Biederman
Now that the uid_t -> kuid_t, gid_t -> kgid_t conversion has been completed in 9p allow 9p to be built when user namespaces are enabled. Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@gmail.com> Cc: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-12ceph: Enable building when user namespaces are enabled.Eric W. Biederman
Now that conversions happen from kuids and kgids when generating ceph messages and conversion happen to kuids and kgids after receiving celph messages, and all intermediate data structures store uids and gids as type kuid_t and kgid_t it is safe to enable ceph with user namespace support enabled. Cc: Sage Weil <sage@inktank.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-08cputime: Restore CPU_ACCOUNTING config defaults for PPC64Stephen Rothwell
Commit abf917cd91cb ("cputime: Generic on-demand virtual cputime accounting") inadvertantly changed the default CPU_ACCOUNTING config for PPC64. Repair that. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: ppc-dev <linuxppc-dev@lists.ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Link: http://lkml.kernel.org/r/20130208141938.f31b7b9e1acac5bbe769ee4c@canb.auug.org.au Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-07sched/rt: Move rt specific bits into new header fileClark Williams
Move rt scheduler definitions out of include/linux/sched.h into new file include/linux/sched/rt.h Signed-off-by: Clark Williams <williams@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20130207094707.7b9f825f@riff.lan Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-07sched: Move sched.h sysctl bits into separate headerClark Williams
Move the sysctl-related bits from include/linux/sched.h into a new file: include/linux/sched/sysctl.h. Then update source files requiring access to those bits by including the new header file. Signed-off-by: Clark Williams <williams@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20130207094659.06dced96@riff.lan Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-06driver-core: constify data for class_find_device()Michał Mirosław
All in-kernel users of class_find_device() don't really need mutable data for match callback. In two places (kernel/power/suspend_test.c, drivers/scsi/osd/osd_uld.c) this patch changes match callbacks to use const search data. The const is propagated to rtc_class_open() and power_supply_get_by_name() parameters. Note that there's a dev reference leak in suspend_test.c that's not touched in this patch. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Acked-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-05Merge tag 'full-dynticks-cputime-for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into sched/core Pull full-dynticks (user-space execution is undisturbed and receives no timer IRQs) preparation changes that convert the cputime accounting code to be full-dynticks ready, from Frederic Weisbecker: "This implements the cputime accounting on full dynticks CPUs. Typical cputime stats infrastructure relies on the timer tick and its periodic polling on the CPU to account the amount of time spent by the CPUs and the tasks per high level domains such as userspace, kernelspace, guest, ... Now we are preparing to implement full dynticks capability on Linux for Real Time and HPC users who want full CPU isolation. This feature requires a cputime accounting that doesn't depend on the timer tick. To implement it, this new cputime infrastructure plugs into kernel/user/guest boundaries to take snapshots of cputime and flush these to the stats when needed. This performs pretty much like CONFIG_VIRT_CPU_ACCOUNTING except that context location and cputime snaphots are synchronized between write and read side such that the latter can safely retrieve the pending tickless cputime of a task and add it to its latest cputime snapshot to return the correct result to the user." Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-02-05Merge branch 'nohz/printk-v8' into irq/coreFrederic Weisbecker
Conflicts: kernel/irq_work.c Add support for printk in full dynticks CPU. * Don't stop tick with irq works pending. This fix is generally useful and concerns archs that can't raise self IPIs. * Flush irq works before CPU offlining. * Introduce "lazy" irq works that can wait for the next tick to be executed, unless it's stopped. * Implement klogd wake up using irq work. This removes the ad-hoc printk_tick()/printk_needs_cpu() hooks and make it working even in dynticks mode. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2013-02-04Merge branch 'rcu/next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: 1. Changes to rcutorture and to RCU documentation. Posted to LKML at https://lkml.org/lkml/2013/1/26/188. 2. Enhancements to uniprocessor handling in tiny RCU. Posted to LKML at https://lkml.org/lkml/2013/1/27/2. 3. Tag RCU callbacks with grace-period number to simplify callback advancement. Posted to LKML at https://lkml.org/lkml/2013/1/26/203. 4. Miscellaneous fixes. Posted to LKML at https://lkml.org/lkml/2013/1/26/204. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-31Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Peter Anvin: "This is a collection of miscellaneous fixes, the most important one is the fix for the Samsung laptop bricking issue (auto-blacklisting the samsung-laptop driver); the efi_enabled() changes you see below are prerequisites for that fix. The other issues fixed are booting on OLPC XO-1.5, an UV fix, NMI debugging, and requiring CAP_SYS_RAWIO for MSR references, just as with I/O port references." * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: samsung-laptop: Disable on EFI hardware efi: Make 'efi_enabled' a function to query EFI facilities smp: Fix SMP function call empty cpu mask race x86/msr: Add capabilities check x86/dma-debug: Bump PREALLOC_DMA_DEBUG_ENTRIES x86/olpc: Fix olpc-xo1-sci.c build errors arch/x86/platform/uv: Fix incorrect tlb flush all issue x86-64: Fix unwind annotations in recent NMI changes x86-32: Start out cr0 clean, disable paging before modifying cr3/4
2013-01-30efi: Make 'efi_enabled' a function to query EFI facilitiesMatt Fleming
Originally 'efi_enabled' indicated whether a kernel was booted from EFI firmware. Over time its semantics have changed, and it now indicates whether or not we are booted on an EFI machine with bit-native firmware, e.g. 64-bit kernel with 64-bit firmware. The immediate motivation for this patch is the bug report at, https://bugs.launchpad.net/ubuntu-cdimage/+bug/1040557 which details how running a platform driver on an EFI machine that is designed to run under BIOS can cause the machine to become bricked. Also, the following report, https://bugzilla.kernel.org/show_bug.cgi?id=47121 details how running said driver can also cause Machine Check Exceptions. Drivers need a new means of detecting whether they're running on an EFI machine, as sadly the expression, if (!efi_enabled) hasn't been a sufficient condition for quite some time. Users actually want to query 'efi_enabled' for different reasons - what they really want access to is the list of available EFI facilities. For instance, the x86 reboot code needs to know whether it can invoke the ResetSystem() function provided by the EFI runtime services, while the ACPI OSL code wants to know whether the EFI config tables were mapped successfully. There are also checks in some of the platform driver code to simply see if they're running on an EFI machine (which would make it a bad idea to do BIOS-y things). This patch is a prereq for the samsung-laptop fix patch. Cc: David Airlie <airlied@linux.ie> Cc: Corentin Chary <corentincj@iksaif.net> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Olof Johansson <olof@lixom.net> Cc: Peter Jones <pjones@redhat.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: Steve Langasek <steve.langasek@canonical.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Konrad Rzeszutek Wilk <konrad@kernel.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-28rcu: Allow TREE_PREEMPT_RCU on UP systemsPaul E. McKenney
The TINY_PREEMPT_RCU is complex, does not provide that much memory savings, and therefore TREE_PREEMPT_RCU should be used instead. The systems where the difference between TINY_PREEMPT_RCU and TREE_PREEMPT_RCU are quite small compared to the memory footprint of CONFIG_PREEMPT. This commit therefore takes a first step towards eliminating TINY_PREEMPT_RCU by allowing TREE_PREEMPT_RCU to be configured on !SMP systems. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-01-28rcu: Provide RCU CPU stall warnings for tiny RCUPaul E. McKenney
Tiny RCU has historically omitted RCU CPU stall warnings in order to reduce memory requirements, however, lack of these warnings caused Thomas Gleixner some debugging pain recently. Therefore, this commit adds RCU CPU stall warnings to tiny RCU if RCU_TRACE=y. This keeps the memory footprint small, while still enabling CPU stall warnings in kernels built to enable them. Updated to include Josh Triplett's suggested use of RCU_STALL_COMMON config variable to simplify #if expressions. Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-01-27cputime: Generic on-demand virtual cputime accountingFrederic Weisbecker
If we want to stop the tick further idle, we need to be able to account the cputime without using the tick. Virtual based cputime accounting solves that problem by hooking into kernel/user boundaries. However implementing CONFIG_VIRT_CPU_ACCOUNTING require low level hooks and involves more overhead. But we already have a generic context tracking subsystem that is required for RCU needs by archs which plan to shut down the tick outside idle. This patch implements a generic virtual based cputime accounting that relies on these generic kernel/user hooks. There are some upsides of doing this: - This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING if context tracking is already built (already necessary for RCU in full tickless mode). - We can rely on the generic context tracking subsystem to dynamically (de)activate the hooks, so that we can switch anytime between virtual and tick based accounting. This way we don't have the overhead of the virtual accounting when the tick is running periodically. And one downside: - There is probably more overhead than a native virtual based cputime accounting. But this relies on hooks that are already set anyway. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de>
2013-01-26userns: Recommend use of memory control groups.Eric W. Biederman
In the help text describing user namespaces recommend use of memory control groups. In many cases memory control groups are the only mechanism there is to limit how much memory a user who can create user namespaces can use. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2013-01-25Merge 3.8-rc5 into driver-core-nextGreg Kroah-Hartman
This resolves a gpio driver merge issue pointed out in linux-next. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-25MODSIGN: Add option to not sign modules during modules_installMichal Marek
To allow the builder to sign only a subset of modules, or to sign the modules using a key that is not available on the build machine, add CONFIG_MODULE_SIG_ALL. If this option is unset, no modules will be signed during build. The default is 'y', to preserve the current behavior. Signed-off-by: Michal Marek <mmarek@suse.cz> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-01-25MODSIGN: Simplify Makefile with a Kconfig helperMichal Marek
Signed-off-by: Michal Marek <mmarek@suse.cz> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-01-24Merge branch 'core/irq_work' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into irq/core irq_work fixes and cleanups, in preparation for full dyntics support. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-01-23Merge branch 'master' into for-3.9-asyncTejun Heo
To receive f56c3196f251012de9b3ebaff55732a9074fdaae ("async: fix __lowest_in_progress()"). Signed-off-by: Tejun Heo <tj@kernel.org>
2013-01-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull misc syscall fixes from Al Viro: - compat syscall fixes (discussed back in December) - a couple of "make life easier for sigaltstack stuff by reducing inter-tree dependencies" - fix up compiler/asmlinkage calling convention disagreement of sys_clone() - misc * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: sys_clone() needs asmlinkage_protect make sure that /linuxrc has std{in,out,err} x32: fix sigtimedwait x32: fix waitid() switch compat_sys_wait4() and compat_sys_waitid() to COMPAT_SYSCALL_DEFINE switch compat_sys_sigaltstack() to COMPAT_SYSCALL_DEFINE CONFIG_GENERIC_SIGALTSTACK build breakage with asm-generic/syscalls.h Ensure that kernel_init_freeable() is not inlined into non __init code
2013-01-19make sure that /linuxrc has std{in,out,err}Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-01-18init, block: try to load default elevator module early during bootTejun Heo
This patch adds default module loading and uses it to load the default block elevator. During boot, it's called right after initramfs or initrd is made available and right before control is passed to userland. This ensures that as long as the modules are available in the usual places in initramfs, initrd or the root filesystem, the default modules are loaded as soon as possible. This will replace the on-demand elevator module loading from elevator init path. v2: Fixed build breakage when !CONFIG_BLOCK. Reported by kbuild test robot. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alex Riesen <raa.lkml@gmail.com> Cc: Fengguang We <fengguang.wu@intel.com>
2013-01-17Merge 3.9-rc4 into driver-core-nextGreg Kroah-Hartman
This is to fix up a build problem with a wireless driver due to the dynamic-debug patches in this branch. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-16Tell the world we gave up on pushing CC_OPTIMIZE_FOR_SIZEKirill Smelkov
In commit 281dc5c5ec0f ("Give up on pushing CC_OPTIMIZE_FOR_SIZE") we already changed the actual default value, but the help-text still suggested 'y'. Fix the help text too, for all the same reasons. Sadly, -Os keeps on generating some very suboptimal code for certain cases, to the point where any I$ miss upside is swamped by the downside. The main ones are: - using "rep movsb" for memcpy, even on CPU's where that is horrendously bad for performance. - not honoring branch prediction information, so any I$ footprint you win from smaller code, you lose from less code density in the I$. - using divide instructions when that is very expensive. Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-11init: remove depends on CONFIG_EXPERIMENTALKees Cook
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a while now and is almost always enabled by default. As agreed during the Linux kernel summit, remove it from any "depends on" lines in Kconfigs. CC: "Eric W. Biederman" <ebiederm@xmission.com> CC: Serge Hallyn <serge.hallyn@canonical.com> CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>
2013-01-11make CONFIG_EXPERIMENTAL invisible and defaultKees Cook
This config item has not carried much meaning for a while now and is almost always enabled by default (especially in distro builds). As agreed during the Linux kernel summit, it should be removed. As a first step, remove it from being listed, and default it to on. Once it has been removed from all subsystem Kconfigs, it will be dropped entirely. For items that really are experimental, maintainers should use "default n", optionally include "(EXPERIMENTAL)" in the title, and add language to the help text indicating why the item should be considered experimental. For items that are dangerously experimental, the maintainer is encouraged to follow the above title recommendation, add stronger language to the help text, and optionally use (depending on the extent of the danger, from least to most dangerous): printk(), add_taint(TAINT_WARN), add_taint(TAINT_CRAP), WARN_ON(1), and CONFIG_BROKEN. CC: Greg KH <gregkh@linuxfoundation.org> CC: "Eric W. Biederman" <ebiederm@xmission.com> CC: Serge Hallyn <serge.hallyn@canonical.com> CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2013-01-09sysctl: Enable IA64 "ignore-unaligned-usertrap" to be used cross-archVineet Gupta
IA64 defines /proc/sys/kernel/ignore-unaligned-usertrap to control verbose warnings on unaligned access emulation. Although the exact mechanics of what to do with sysctl (ignore/shout) are arch specific, this change enables the sysctl to be usable cross-arch. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2012-12-26Ensure that kernel_init_freeable() is not inlined into non __init codeVineet Gupta
Commit d6b2123802d "make sure that we always have a return path from kernel_execve()" reshuffled kernel_init()/init_post() to ensure that kernel_execve() has a caller to return to. It removed __init annotation for kernel_init() and introduced/calls a new routine kernel_init_freeable(). Latter however is inlined by any reasonable compiler (ARC gcc 4.4 in this case), causing slight code bloat. This patch forces kernel_init_freeable() as noinline reducing the .text bloat-o-meter vmlinux vmlinux_new add/remove: 1/0 grow/shrink: 0/1 up/down: 374/-334 (40) function old new delta kernel_init_freeable - 374 +374 (.init.text) kernel_init 628 294 -334 (.text) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull signal handling cleanups from Al Viro: "sigaltstack infrastructure + conversion for x86, alpha and um, COMPAT_SYSCALL_DEFINE infrastructure. Note that there are several conflicts between "unify SS_ONSTACK/SS_DISABLE definitions" and UAPI patches in mainline; resolution is trivial - just remove definitions of SS_ONSTACK and SS_DISABLED from arch/*/uapi/asm/signal.h; they are all identical and include/uapi/linux/signal.h contains the unified variant." Fixed up conflicts as per Al. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: alpha: switch to generic sigaltstack new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those generic compat_sys_sigaltstack() introduce generic sys_sigaltstack(), switch x86 and um to it new helper: compat_user_stack_pointer() new helper: restore_altstack() unify SS_ONSTACK/SS_DISABLE definitions new helper: current_user_stack_pointer() missing user_stack_pointer() instances Bury the conditionals from kernel_thread/kernel_execve series COMPAT_SYSCALL_DEFINE: infrastructure
2012-12-19Bury the conditionals from kernel_thread/kernel_execve seriesAl Viro
All architectures have CONFIG_GENERIC_KERNEL_THREAD CONFIG_GENERIC_KERNEL_EXECVE __ARCH_WANT_SYS_EXECVE None of them have __ARCH_WANT_KERNEL_EXECVE and there are only two callers of kernel_execve() (which is a trivial wrapper for do_execve() now) left. Kill the conditionals and make both callers use do_execve(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>