Commit Graph

256 Commits

Author SHA1 Message Date
Nathan Chancellor a626beca4c This is the 3.10.105 stable release
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Merge 3.10.105 into android-msm-bullhead-3.10-oreo-m5

Changes in 3.10.105: (315 commits)
        sched/core: Fix a race between try_to_wake_up() and a woken up task
        sched/core: Fix an SMP ordering race in try_to_wake_up() vs. schedule()
        crypto: algif_skcipher - Require setkey before accept(2)
        crypto: af_alg - Disallow bind/setkey/... after accept(2)
        crypto: af_alg - Add nokey compatibility path
        crypto: algif_skcipher - Add nokey compatibility path
        crypto: hash - Add crypto_ahash_has_setkey
        crypto: shash - Fix has_key setting
        crypto: algif_hash - Require setkey before accept(2)
        crypto: skcipher - Add crypto_skcipher_has_setkey
        crypto: algif_skcipher - Add key check exception for cipher_null
        crypto: af_alg - Allow af_af_alg_release_parent to be called on nokey path
        crypto: algif_hash - Remove custom release parent function
        crypto: algif_skcipher - Remove custom release parent function
        crypto: af_alg - Forbid bind(2) when nokey child sockets are present
        crypto: algif_hash - Fix race condition in hash_check_key
        crypto: algif_skcipher - Fix race condition in skcipher_check_key
        crypto: algif_skcipher - Load TX SG list after waiting
        crypto: cryptd - initialize child shash_desc on import
        crypto: skcipher - Fix blkcipher walk OOM crash
        crypto: gcm - Fix IV buffer size in crypto_gcm_setkey
        MIPS: KVM: Fix unused variable build warning
        KVM: MIPS: Precalculate MMIO load resume PC
        KVM: MIPS: Drop other CPU ASIDs on guest MMU changes
        KVM: nVMX: postpone VMCS changes on MSR_IA32_APICBASE write
        KVM: MIPS: Make ERET handle ERL before EXL
        KVM: x86: fix wbinvd_dirty_mask use-after-free
        KVM: x86: fix missed SRCU usage in kvm_lapic_set_vapic_addr
        KVM: Disable irq while unregistering user notifier
        PM / devfreq: Fix incorrect type issue.
        ppp: defer netns reference release for ppp channel
        x86/mm/xen: Suppress hugetlbfs in PV guests
        xen: Add RING_COPY_REQUEST()
        xen-netback: don't use last request to determine minimum Tx credit
        xen-netback: use RING_COPY_REQUEST() throughout
        xen-blkback: only read request operation from shared ring once
        xen/pciback: Save xen_pci_op commands before processing it
        xen/pciback: Save the number of MSI-X entries to be copied later.
        xen/pciback: Return error on XEN_PCI_OP_enable_msi when device has MSI or MSI-X enabled
        xen/pciback: Return error on XEN_PCI_OP_enable_msix when device has MSI or MSI-X enabled
        xen/pciback: Do not install an IRQ handler for MSI interrupts.
        xen/pciback: For XEN_PCI_OP_disable_msi[|x] only disable if device has MSI(X) enabled.
        xen/pciback: Don't allow MSI-X ops if PCI_COMMAND_MEMORY is not set.
        xen-pciback: Add name prefix to global 'permissive' variable
        x86/xen: fix upper bound of pmd loop in xen_cleanhighmap()
        x86/traps: Ignore high word of regs->cs in early_idt_handler_common
        x86/mm: Disable preemption during CR3 read+write
        x86/apic: Do not init irq remapping if ioapic is disabled
        x86/mm/pat, /dev/mem: Remove superfluous error message
        x86/paravirt: Do not trace _paravirt_ident_*() functions
        x86/build: Build compressed x86 kernels as PIE
        x86/um: reuse asm-generic/barrier.h
        iommu/amd: Update Alias-DTE in update_device_table()
        iommu/amd: Free domain id when free a domain of struct dma_ops_domain
        ARM: 8616/1: dt: Respect property size when parsing CPUs
        ARM: 8618/1: decompressor: reset ttbcr fields to use TTBR0 on ARMv7
        ARM: sa1100: clear reset status prior to reboot
        ARM: sa1111: fix pcmcia suspend/resume
        arm64: avoid returning from bad_mode
        arm64: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO
        arm64: spinlocks: implement smp_mb__before_spinlock() as smp_mb()
        arm64: debug: avoid resetting stepping state machine when TIF_SINGLESTEP
        MIPS: Malta: Fix IOCU disable switch read for MIPS64
        MIPS: ptrace: Fix regs_return_value for kernel context
        powerpc/mm: Don't alias user region to other regions below PAGE_OFFSET
        powerpc/vdso64: Use double word compare on pointers
        powerpc/powernv: Use CPU-endian PEST in pnv_pci_dump_p7ioc_diag_data()
        powerpc/64: Fix incorrect return value from __copy_tofrom_user
        powerpc/nvram: Fix an incorrect partition merge
        avr32: fix copy_from_user()
        avr32: fix 'undefined reference to `___copy_from_user'
        avr32: off by one in at32_init_pio()
        s390/dasd: fix hanging device after clear subchannel
        parisc: Ensure consistent state when switching to kernel stack at syscall entry
        microblaze: fix __get_user()
        microblaze: fix copy_from_user()
        mn10300: failing __get_user() and get_user() should zero
        m32r: fix __get_user()
        sh64: failing __get_user() should zero
        score: fix __get_user/get_user
        s390: get_user() should zero on failure
        ARC: uaccess: get_user to zero out dest in cause of fault
        asm-generic: make get_user() clear the destination on errors
        frv: fix clear_user()
        cris: buggered copy_from_user/copy_to_user/clear_user
        blackfin: fix copy_from_user()
        score: fix copy_from_user() and friends
        sh: fix copy_from_user()
        hexagon: fix strncpy_from_user() error return
        mips: copy_from_user() must zero the destination on access_ok() failure
        asm-generic: make copy_from_user() zero the destination properly
        alpha: fix copy_from_user()
        metag: copy_from_user() should zero the destination on access_ok() failure
        parisc: fix copy_from_user()
        openrisc: fix copy_from_user()
        openrisc: fix the fix of copy_from_user()
        mn10300: copy_from_user() should zero on access_ok() failure...
        sparc32: fix copy_from_user()
        ppc32: fix copy_from_user()
        ia64: copy_from_user() should zero the destination on access_ok() failure
        fix fault_in_multipages_...() on architectures with no-op access_ok()
        fix memory leaks in tracing_buffers_splice_read()
        arc: don't leak bits of kernel stack into coredump
        Fix potential infoleak in older kernels
        swapfile: fix memory corruption via malformed swapfile
        coredump: fix unfreezable coredumping task
        usb: dwc3: gadget: increment request->actual once
        USB: validate wMaxPacketValue entries in endpoint descriptors
        USB: fix typo in wMaxPacketSize validation
        usb: xhci: Fix panic if disconnect
        USB: serial: fix memleak in driver-registration error path
        USB: kobil_sct: fix non-atomic allocation in write path
        USB: serial: mos7720: fix non-atomic allocation in write path
        USB: serial: mos7840: fix non-atomic allocation in write path
        usb: renesas_usbhs: fix clearing the {BRDY,BEMP}STS condition
        USB: change bInterval default to 10 ms
        usb: gadget: fsl_qe_udc: signedness bug in qe_get_frame()
        USB: serial: cp210x: fix hardware flow-control disable
        usb: misc: legousbtower: Fix NULL pointer deference
        usb: gadget: function: u_ether: don't starve tx request queue
        USB: serial: cp210x: fix tiocmget error handling
        usb: gadget: u_ether: remove interrupt throttling
        usb: chipidea: move the lock initialization to core file
        Fix USB CB/CBI storage devices with CONFIG_VMAP_STACK=y
        ALSA: rawmidi: Fix possible deadlock with virmidi registration
        ALSA: timer: fix NULL pointer dereference in read()/ioctl() race
        ALSA: timer: fix division by zero after SNDRV_TIMER_IOCTL_CONTINUE
        ALSA: timer: fix NULL pointer dereference on memory allocation failure
        ALSA: ali5451: Fix out-of-bound position reporting
        ALSA: pcm : Call kill_fasync() in stream lock
        zfcp: fix fc_host port_type with NPIV
        zfcp: fix ELS/GS request&response length for hardware data router
        zfcp: close window with unblocked rport during rport gone
        zfcp: retain trace level for SCSI and HBA FSF response records
        zfcp: restore: Dont use 0 to indicate invalid LUN in rec trace
        zfcp: trace on request for open and close of WKA port
        zfcp: restore tracing of handle for port and LUN with HBA records
        zfcp: fix D_ID field with actual value on tracing SAN responses
        zfcp: fix payload trace length for SAN request&response
        zfcp: trace full payload of all SAN records (req,resp,iels)
        scsi: zfcp: spin_lock_irqsave() is not nestable
        scsi: mpt3sas: Fix secure erase premature termination
        scsi: mpt3sas: Unblock device after controller reset
        scsi: mpt3sas: fix hang on ata passthrough commands
        mpt2sas: Fix secure erase premature termination
        scsi: megaraid_sas: Fix data integrity failure for JBOD (passthrough) devices
        scsi: megaraid_sas: fix macro MEGASAS_IS_LOGICAL to avoid regression
        scsi: ibmvfc: Fix I/O hang when port is not mapped
        scsi: Fix use-after-free
        scsi: arcmsr: Buffer overflow in arcmsr_iop_message_xfer()
        scsi: scsi_debug: Fix memory leak if LBP enabled and module is unloaded
        scsi: arcmsr: Send SYNCHRONIZE_CACHE command to firmware
        ext4: validate that metadata blocks do not overlap superblock
        ext4: avoid modifying checksum fields directly during checksum verification
        ext4: use __GFP_NOFAIL in ext4_free_blocks()
        ext4: reinforce check of i_dtime when clearing high fields of uid and gid
        ext4: allow DAX writeback for hole punch
        ext4: sanity check the block and cluster size at mount time
        reiserfs: fix "new_insert_key may be used uninitialized ..."
        reiserfs: Unlock superblock before calling reiserfs_quota_on_mount()
        xfs: fix superblock inprogress check
        libxfs: clean up _calc_dquots_per_chunk
        btrfs: ensure that file descriptor used with subvol ioctls is a dir
        ocfs2/dlm: fix race between convert and migration
        ocfs2: fix start offset to ocfs2_zero_range_for_truncate()
        ubifs: Fix assertion in layout_in_gaps()
        ubifs: Fix xattr_names length in exit paths
        UBIFS: Fix possible memory leak in ubifs_readdir()
        ubifs: Abort readdir upon error
        ubifs: Fix regression in ubifs_readdir()
        UBI: fastmap: scrub PEB when bitflips are detected in a free PEB EC header
        NFSv4.x: Fix a refcount leak in nfs_callback_up_net
        NFSD: Using free_conn free connection
        NFS: Don't drop CB requests with invalid principals
        NFSv4: Open state recovery must account for file permission changes
        fs/seq_file: fix out-of-bounds read
        fs/super.c: fix race between freeze_super() and thaw_super()
        isofs: Do not return EACCES for unknown filesystems
        hostfs: Freeing an ERR_PTR in hostfs_fill_sb_common()
        driver core: Delete an unnecessary check before the function call "put_device"
        driver core: fix race between creating/querying glue dir and its cleanup
        drm/radeon: fix radeon_move_blit on 32bit systems
        drm: Reject page_flip for !DRIVER_MODESET
        drm/radeon: Ensure vblank interrupt is enabled on DPMS transition to on
        qxl: check for kmap failures
        Input: i8042 - break load dependency between atkbd/psmouse and i8042
        Input: i8042 - set up shared ps2_cmd_mutex for AUX ports
        Input: ili210x - fix permissions on "calibrate" attribute
        hwrng: exynos - Disable runtime PM on probe failure
        hwrng: omap - Fix assumption that runtime_get_sync will always succeed
        hwrng: omap - Only fail if pm_runtime_get_sync returns < 0
        i2c-eg20t: fix race between i2c init and interrupt enable
        em28xx-i2c: rt_mutex_trylock() returns zero on failure
        i2c: core: fix NULL pointer dereference under race condition
        i2c: at91: fix write transfers by clearing pending interrupt first
        iio: accel: kxsd9: Fix raw read return
        iio: accel: kxsd9: Fix scaling bug
        thermal: hwmon: Properly report critical temperature in sysfs
        cdc-acm: fix wrong pipe type on rx interrupt xfers
        timers: Use proper base migration in add_timer_on()
        EDAC: Increment correct counter in edac_inc_ue_error()
        IB/ipoib: Fix memory corruption in ipoib cm mode connect flow
        IB/core: Fix use after free in send_leave function
        IB/ipoib: Don't allow MC joins during light MC flush
        IB/mlx4: Fix incorrect MC join state bit-masking on SR-IOV
        IB/mlx4: Fix create CQ error flow
        IB/uverbs: Fix leak of XRC target QPs
        IB/cm: Mark stale CM id's whenever the mad agent was unregistered
        mtd: blkdevs: fix potential deadlock + lockdep warnings
        mtd: pmcmsp-flash: Allocating too much in init_msp_flash()
        mtd: nand: davinci: Reinitialize the HW ECC engine in 4bit hwctl
        perf symbols: Fixup symbol sizes before picking best ones
        perf: Tighten (and fix) the grouping condition
        tty: Prevent ldisc drivers from re-using stale tty fields
        tty: limit terminal size to 4M chars
        tty: vt, fix bogus division in csi_J
        vt: clear selection before resizing
        drivers/vfio: Rework offsetofend()
        include/stddef.h: Move offsetofend() from vfio.h to a generic kernel header
        stddef.h: move offsetofend inside #ifndef/#endif guard, neaten
        ipv6: don't call fib6_run_gc() until routing is ready
        ipv6: split duplicate address detection and router solicitation timer
        ipv6: move DAD and addrconf_verify processing to workqueue
        ipv6: addrconf: fix dev refcont leak when DAD failed
        ipv6: fix rtnl locking in setsockopt for anycast and multicast
        ip6_gre: fix flowi6_proto value in ip6gre_xmit_other()
        ipv6: correctly add local routes when lo goes up
        ipv6: dccp: fix out of bound access in dccp_v6_err()
        ipv6: dccp: add missing bind_conflict to dccp_ipv6_mapped
        ip6_tunnel: Clear IP6CB in ip6tunnel_xmit()
        ip6_tunnel: disable caching when the traffic class is inherited
        net/irda: handle iriap_register_lsap() allocation failure
        tcp: fix use after free in tcp_xmit_retransmit_queue()
        tcp: properly scale window in tcp_v[46]_reqsk_send_ack()
        tcp: fix overflow in __tcp_retransmit_skb()
        tcp: fix wrong checksum calculation on MTU probing
        tcp: take care of truncations done by sk_filter()
        bonding: Fix bonding crash
        net: ratelimit warnings about dst entry refcount underflow or overflow
        mISDN: Support DR6 indication in mISDNipac driver
        mISDN: Fixing missing validation in base_sock_bind()
        net: disable fragment reassembly if high_thresh is set to zero
        ipvs: count pre-established TCP states as active
        iwlwifi: pcie: fix access to scratch buffer
        svc: Avoid garbage replies when pc_func() returns rpc_drop_reply
        brcmsmac: Free packet if dma_mapping_error() fails in dma_rxfill
        brcmsmac: Initialize power in brcms_c_stf_ss_algo_channel_get()
        brcmfmac: avoid potential stack overflow in brcmf_cfg80211_start_ap()
        pstore: Fix buffer overflow while write offset equal to buffer size
        net/mlx4_core: Allow resetting VF admin mac to zero
        firewire: net: guard against rx buffer overflows
        firewire: net: fix fragmented datagram_size off-by-one
        netfilter: fix namespace handling in nf_log_proc_dostring
        can: bcm: fix warning in bcm_connect/proc_register
        net: fix sk_mem_reclaim_partial()
        net: avoid sk_forward_alloc overflows
        ipmr, ip6mr: fix scheduling while atomic and a deadlock with ipmr_get_route
        packet: call fanout_release, while UNREGISTERING a netdev
        net: sctp, forbid negative length
        sctp: validate chunk len before actually using it
        net: clear sk_err_soft in sk_clone_lock()
        net: mangle zero checksum in skb_checksum_help()
        dccp: do not send reset to already closed sockets
        dccp: fix out of bound access in dccp_v4_err()
        sctp: assign assoc_id earlier in __sctp_connect
        neigh: check error pointer instead of NULL for ipv4_neigh_lookup()
        ipv4: use new_gw for redirect neigh lookup
        mac80211: fix purging multicast PS buffer queue
        mac80211: discard multicast and 4-addr A-MSDUs
        cfg80211: limit scan results cache size
        mwifiex: printk() overflow with 32-byte SSIDs
        ipv4: Set skb->protocol properly for local output
        net: sky2: Fix shutdown crash
        kaweth: fix firmware download
        tracing: Move mutex to protect against resetting of seq data
        kernel/fork: fix CLONE_CHILD_CLEARTID regression in nscd
        Revert "ipc/sem.c: optimize sem_lock()"
        cfq: fix starvation of asynchronous writes
        drbd: Fix kernel_sendmsg() usage - potential NULL deref
        lib/genalloc.c: start search from start of chunk
        tools/vm/slabinfo: fix an unintentional printf
        rcu: Fix soft lockup for rcu_nocb_kthread
        ratelimit: fix bug in time interval by resetting right begin time
        mfd: core: Fix device reference leak in mfd_clone_cell
        PM / sleep: fix device reference leak in test_suspend
        mmc: mxs: Initialize the spinlock prior to using it
        mmc: block: don't use CMD23 with very old MMC cards
        pstore/core: drop cmpxchg based updates
        pstore/ram: Use memcpy_toio instead of memcpy
        pstore/ram: Use memcpy_fromio() to save old buffer
        mb86a20s: fix the locking logic
        mb86a20s: fix demod settings
        cx231xx: don't return error on success
        cx231xx: fix GPIOs for Pixelview SBTVD hybrid
        gpio: mpc8xxx: Correct irq handler function
        uio: fix dmem_region_start computation
        KEYS: Fix short sprintf buffer in /proc/keys show function
        hv: do not lose pending heartbeat vmbus packets
        staging: iio: ad5933: avoid uninitialized variable in error case
        mei: bus: fix received data size check in NFC fixup
        ACPI / APEI: Fix incorrect return value of ghes_proc()
        PCI: Handle read-only BARs on AMD CS553x devices
        tile: avoid using clocksource_cyc2ns with absolute cycle count
        dm flakey: fix reads to be issued if drop_writes configured
        mm,ksm: fix endless looping in allocating memory when ksm enable
        can: dev: fix deadlock reported after bus-off
        hwmon: (adt7411) set bit 3 in CFG1 register
        mpi: Fix NULL ptr dereference in mpi_powm() [ver #3]
        mfd: 88pm80x: Double shifting bug in suspend/resume
        ASoC: omap-mcpdm: Fix irq resource handling
        regulator: tps65910: Work around silicon erratum SWCZ010
        dm: mark request_queue dead before destroying the DM device
        fbdev/efifb: Fix 16 color palette entry calculation
        metag: Only define atomic_dec_if_positive conditionally
        Linux 3.10.105

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Conflicts:
	arch/arm/mach-sa1100/generic.c
	arch/arm64/kernel/traps.c
	crypto/blkcipher.c
	drivers/devfreq/devfreq.c
	drivers/usb/dwc3/gadget.c
	drivers/usb/gadget/u_ether.c
	fs/ubifs/dir.c
	include/net/if_inet6.h
	lib/genalloc.c
	net/ipv6/addrconf.c
	net/ipv6/tcp_ipv6.c
	net/wireless/scan.c
	sound/core/timer.c
2018-01-25 17:45:32 -07:00
Tejun Heo de3e6236be timers: Use proper base migration in add_timer_on()
commit 22b886dd1018093920c4250dee2a9a3cb7cff7b8 upstream.

Regardless of the previous CPU a timer was on, add_timer_on()
currently simply sets timer->flags to the new CPU.  As the caller must
be seeing the timer as idle, this is locally fine, but the timer
leaving the old base while unlocked can lead to race conditions as
follows.

Let's say timer was on cpu 0.

  cpu 0					cpu 1
  -----------------------------------------------------------------------------
  del_timer(timer) succeeds
					del_timer(timer)
					  lock_timer_base(timer) locks cpu_0_base
  add_timer_on(timer, 1)
    spin_lock(&cpu_1_base->lock)
    timer->flags set to cpu_1_base
    operates on @timer			  operates on @timer

This triggered with mod_delayed_work_on() which contains
"if (del_timer()) add_timer_on()" sequence eventually leading to the
following oops.

  BUG: unable to handle kernel NULL pointer dereference at           (null)
  IP: [<ffffffff810ca6e9>] detach_if_pending+0x69/0x1a0
  ...
  Workqueue: wqthrash wqthrash_workfunc [wqthrash]
  task: ffff8800172ca680 ti: ffff8800172d0000 task.ti: ffff8800172d0000
  RIP: 0010:[<ffffffff810ca6e9>]  [<ffffffff810ca6e9>] detach_if_pending+0x69/0x1a0
  ...
  Call Trace:
   [<ffffffff810cb0b4>] del_timer+0x44/0x60
   [<ffffffff8106e836>] try_to_grab_pending+0xb6/0x160
   [<ffffffff8106e913>] mod_delayed_work_on+0x33/0x80
   [<ffffffffa0000081>] wqthrash_workfunc+0x61/0x90 [wqthrash]
   [<ffffffff8106dba8>] process_one_work+0x1e8/0x650
   [<ffffffff8106e05e>] worker_thread+0x4e/0x450
   [<ffffffff810746af>] kthread+0xef/0x110
   [<ffffffff8185980f>] ret_from_fork+0x3f/0x70

Fix it by updating add_timer_on() to perform proper migration as
__mod_timer() does.

Mike: apply tglx backport

Reported-and-tested-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Worley <chris.worley@primarydata.com>
Cc: bfields@fieldses.org
Cc: Michael Skralivetsky <michael.skralivetsky@primarydata.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: kernel-team@fb.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20151029103113.2f893924@tlielax.poochiereds.net
Link: http://lkml.kernel.org/r/20151104171533.GI5749@mtj.duckdns.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Mike Galbraith <mgalbraith@suse.de>
Signed-off-by: Willy Tarreau <w@1wt.eu>
2017-02-10 11:03:36 +01:00
Peter Zijlstra ba58c599fd UPSTREAM: sched: Introduce preempt_count accessor functions
Replace the single preempt_count() 'function' that's an lvalue with
two proper functions:

 preempt_count() - returns the preempt_count value as rvalue
 preempt_count_set() - Allows setting the preempt-count value

Also provide preempt_count_ptr() as a convenience wrapper to implement
all modifying operations.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-orxrbycjozopqfhb4dxdkdvb@git.kernel.org
[ Fixed build failure. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Bug: 28705983
(cherry picked from commit 4a2b4b222743bb07fedf985b884550f2ca067ea9)
Change-Id: I1f74e16f9a30d9fdf5f2439d32853568fa68baaa
2016-07-22 15:56:25 -07:00
Joonwoo Park 63a7d736b1 timer: reduce cache bouncing of deferral timer wheel
Commit a40f752 (timer: make deferrable cpu unbound timers really not
bound to a cpu) made any non-idle CPUs in the system can service expired
deferral timer entries.  This means deferral timer entries can be
serviced as early as possible after it expires but in many cases it's
suboptimal since switching the CPU of timer wheel incurs a cache
bouncing/synchronization cost.

Reduce cache bouncing by servicing the deferrable timer wheel with timer
tick CPU as it doesn't bounce as often but still guarantees to run timer
softirq when there is any CPU that isn't idle.

CRs-fixed: 815184
Change-Id: I6d51390832538ad90eccf459e90bff0b25aad09f
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
2015-05-04 22:44:52 -07:00
Joonwoo Park a40f7521f8 timer: make deferrable cpu unbound timers really not bound to a cpu
When a deferrable work (INIT_DEFERRABLE_WORK, etc.) is queued via
queue_delayed_work() it's probably intended to run the work item on any
CPU that isn't idle. However, we queue the work to run at a later time
by starting a deferrable timer that binds to whatever CPU the work is
queued on which is same with queue_delayed_work_on(smp_processor_id())
effectively.

As a result WORK_CPU_UNBOUND work items aren't really cpu unbound now.
In fact this is perfectly fine with UP kernel and also won't affect much a
system without dyntick with SMP kernel too as every cpus run timers
periodically.  But on SMP systems with dyntick current implementation leads
deferrable timers not very scalable because the timer's base which has
queued the deferrable timer won't wake up till next non-deferrable timer
expires even though there are possible other non idle cpus are running
which are able to run expired deferrable timers.

The deferrable work is a good example of the current implementation's
victim like below.

INIT_DEFERRABLE_WORK(&dwork, fn);
CPU 0                                 CPU 1
queue_delayed_work(wq, &dwork, HZ);
    queue_delayed_work_on(WORK_CPU_UNBOUND);
        ...
	__mod_timer() -> queues timer to the
			 current cpu's timer
			 base.
	...
tick_nohz_idle_enter() -> cpu enters idle.
A second later
cpu 0 is now in idle.                 cpu 1 exits idle or wasn't in idle so
                                      now it's in active but won't
cpu 0 won't wake up till next         handle cpu unbound deferrable timer
non-deferrable timer expires.         as it's in cpu 0's timer base.

To make all cpu unbound deferrable timers are scalable, introduce a common
timer base which is only for cpu unbound deferrable timers to make those
are indeed cpu unbound, so they can be scheduled by any non-idle cpu.
This common timer fixes the scalability issue of delayed work and all other
cpu unbound deferrable timer using implementations.

CRs-fixed: 708770
Change-Id: I83b16fa9e1e3f42808d68fc626dc276bfd556012
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
2014-09-18 14:07:38 -07:00
Ian Maund 6440f462f9 Merge upstream tag 'v3.10.49' into msm-3.10
* commit 'v3.10.49': (529 commits)
  Linux 3.10.49
  ACPI / battery: Retry to get battery information if failed during probing
  x86, ioremap: Speed up check for RAM pages
  Score: Modify the Makefile of Score, remove -mlong-calls for compiling
  Score: The commit is for compiling successfully.
  Score: Implement the function csum_ipv6_magic
  score: normalize global variables exported by vmlinux.lds
  rtmutex: Plug slow unlock race
  rtmutex: Handle deadlock detection smarter
  rtmutex: Detect changes in the pi lock chain
  rtmutex: Fix deadlock detector for real
  ring-buffer: Check if buffer exists before polling
  drm/radeon: stop poisoning the GART TLB
  drm/radeon: fix typo in golden register setup on evergreen
  ext4: disable synchronous transaction batching if max_batch_time==0
  ext4: clarify error count warning messages
  ext4: fix unjournalled bg descriptor while initializing inode bitmap
  dm io: fix a race condition in the wake up code for sync_io
  Drivers: hv: vmbus: Fix a bug in the channel callback dispatch code
  clk: spear3xx: Use proper control register offset
  ...

In addition to bringing in upstream commits, this merge also makes minor
changes to mainitain compatibility with upstream:

The definition of list_next_entry in qcrypto.c and ipa_dp.c has been
removed, as upstream has moved the definition to list.h. The implementation
of list_next_entry was identical between the two.

irq.c, for both arm and arm64 architecture, has had its calls to
__irq_set_affinity_locked updated to reflect changes to the API upstream.

Finally, as we have removed the sleep_length member variable of the
tick_sched struct, all changes made by upstream commit ec804bd do not
apply to our tree and have been removed from this merge. Only
kernel/time/tick-sched.c is impacted.

Change-Id: I63b7e0c1354812921c94804e1f3b33d1ad6ee3f1
Signed-off-by: Ian Maund <imaund@codeaurora.org>
2014-08-20 13:23:09 -07:00
Jiri Bohac 44d4037eb7 timer: Prevent overflow in apply_slack
commit 98a01e779f3c66b0b11cd7e64d531c0e41c95762 upstream.

On architectures with sizeof(int) < sizeof (long), the
computation of mask inside apply_slack() can be undefined if the
computed bit is > 32.

E.g. with: expires = 0xffffe6f5 and slack = 25, we get:

expires_limit = 0x20000000e
bit = 33
mask = (1 << 33) - 1  /* undefined */

On x86, mask becomes 1 and and the slack is not applied properly.
On s390, mask is -1, expires is set to 0 and the timer fires immediately.

Use 1UL << bit to solve that issue.

Suggested-by: Deborah Townsend <dstownse@us.ibm.com>
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Link: http://lkml.kernel.org/r/20140418152310.GA13654@midget.suse.cz
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-07 13:25:30 -07:00
Ian Maund f1b32d4e47 Merge upstream linux-stable v3.10.28 into msm-3.10
The following commits have been reverted from this merge, as they are
known to introduce new bugs and are currently incompatible with our
audio implementation. Investigation of these commits is ongoing, and
they are expected to be brought in at a later time:

86e6de7 ALSA: compress: fix drain calls blocking other compress functions (v6)
16442d4 ALSA: compress: fix drain calls blocking other compress functions

This merge commit also includes a change in block, necessary for
compilation. Upstream has modified elevator_init_fn to prevent race
conditions, requring updates to row_init_queue and test_init_queue.

* commit 'v3.10.28': (1964 commits)
  Linux 3.10.28
  ARM: 7938/1: OMAP4/highbank: Flush L2 cache before disabling
  drm/i915: Don't grab crtc mutexes in intel_modeset_gem_init()
  serial: amba-pl011: use port lock to guard control register access
  mm: Make {,set}page_address() static inline if WANT_PAGE_VIRTUAL
  md/raid5: Fix possible confusion when multiple write errors occur.
  md/raid10: fix two bugs in handling of known-bad-blocks.
  md/raid10: fix bug when raid10 recovery fails to recover a block.
  md: fix problem when adding device to read-only array with bitmap.
  drm/i915: fix DDI PLLs HW state readout code
  nilfs2: fix segctor bug that causes file system corruption
  thp: fix copy_page_rep GPF by testing is_huge_zero_pmd once only
  ftrace/x86: Load ftrace_ops in parameter not the variable holding it
  SELinux: Fix possible NULL pointer dereference in selinux_inode_permission()
  writeback: Fix data corruption on NFS
  hwmon: (coretemp) Fix truncated name of alarm attributes
  vfs: In d_path don't call d_dname on a mount point
  staging: comedi: adl_pci9111: fix incorrect irq passed to request_irq()
  staging: comedi: addi_apci_1032: fix subdevice type/flags bug
  mm/memory-failure.c: recheck PageHuge() after hugetlb page migrate successfully
  GFS2: Increase i_writecount during gfs2_setattr_chown
  perf/x86/amd/ibs: Fix waking up from S3 for AMD family 10h
  perf scripting perl: Fix build error on Fedora 12
  ARM: 7815/1: kexec: offline non panic CPUs on Kdump panic
  Linux 3.10.27
  sched: Guarantee new group-entities always have weight
  sched: Fix hrtimer_cancel()/rq->lock deadlock
  sched: Fix cfs_bandwidth misuse of hrtimer_expires_remaining
  sched: Fix race on toggling cfs_bandwidth_used
  x86, fpu, amd: Clear exceptions in AMD FXSAVE workaround
  netfilter: nf_nat: fix access to uninitialized buffer in IRC NAT helper
  SCSI: sd: Reduce buffer size for vpd request
  intel_pstate: Add X86_FEATURE_APERFMPERF to cpu match parameters.
  mac80211: move "bufferable MMPDU" check to fix AP mode scan
  ACPI / Battery: Add a _BIX quirk for NEC LZ750/LS
  ACPI / TPM: fix memory leak when walking ACPI namespace
  mfd: rtsx_pcr: Disable interrupts before cancelling delayed works
  clk: exynos5250: fix sysmmu_mfc{l,r} gate clocks
  clk: samsung: exynos5250: Add CLK_IGNORE_UNUSED flag for the sysreg clock
  clk: samsung: exynos4: Correct SRC_MFC register
  clk: clk-divider: fix divisor > 255 bug
  ahci: add PCI ID for Marvell 88SE9170 SATA controller
  parisc: Ensure full cache coherency for kmap/kunmap
  drm/nouveau/bios: make jump conditional
  ARM: shmobile: mackerel: Fix coherent DMA mask
  ARM: shmobile: armadillo: Fix coherent DMA mask
  ARM: shmobile: kzm9g: Fix coherent DMA mask
  ARM: dts: exynos5250: Fix MDMA0 clock number
  ARM: fix "bad mode in ... handler" message for undefined instructions
  ARM: fix footbridge clockevent device
  net: Loosen constraints for recalculating checksum in skb_segment()
  bridge: use spin_lock_bh() in br_multicast_set_hash_max
  netpoll: Fix missing TXQ unlock and and OOPS.
  net: llc: fix use after free in llc_ui_recvmsg
  virtio-net: fix refill races during restore
  virtio_net: don't leak memory or block when too many frags
  virtio-net: make all RX paths handle errors consistently
  virtio_net: fix error handling for mergeable buffers
  vlan: Fix header ops passthru when doing TX VLAN offload.
  net: rose: restore old recvmsg behavior
  rds: prevent dereference of a NULL device
  ipv6: always set the new created dst's from in ip6_rt_copy
  net: fec: fix potential use after free
  hamradio/yam: fix info leak in ioctl
  drivers/net/hamradio: Integer overflow in hdlcdrv_ioctl()
  net: inet_diag: zero out uninitialized idiag_{src,dst} fields
  ip_gre: fix msg_name parsing for recvfrom/recvmsg
  net: unix: allow bind to fail on mutex lock
  ipv6: fix illegal mac_header comparison on 32bit
  netvsc: don't flush peers notifying work during setting mtu
  tg3: Initialize REG_BASE_ADDR at PCI config offset 120 to 0
  net: unix: allow set_peek_off to fail
  net: drop_monitor: fix the value of maxattr
  ipv6: don't count addrconf generated routes against gc limit
  packet: fix send path when running with proto == 0
  virtio: delete napi structures from netdev before releasing memory
  macvtap: signal truncated packets
  tun: update file current position
  macvtap: update file current position
  macvtap: Do not double-count received packets
  rds: prevent BUG_ON triggered on congestion update to loopback
  net: do not pretend FRAGLIST support
  IPv6: Fixed support for blackhole and prohibit routes
  HID: Revert "Revert "HID: Fix logitech-dj: missing Unifying device issue""
  gpio-rcar: R-Car GPIO IRQ share interrupt
  clocksource: em_sti: Set cpu_possible_mask to fix SMP broadcast
  irqchip: renesas-irqc: Fix irqc_probe error handling
  Linux 3.10.26
  sh: add EXPORT_SYMBOL(min_low_pfn) and EXPORT_SYMBOL(max_low_pfn) to sh_ksyms_32.c
  ext4: fix bigalloc regression
  arm64: Use Normal NonCacheable memory for writecombine
  arm64: Do not flush the D-cache for anonymous pages
  arm64: Avoid cache flushing in flush_dcache_page()
  ARM: KVM: arch_timers: zero CNTVOFF upon return to host
  ARM: hyp: initialize CNTVOFF to zero
  clocksource: arch_timer: use virtual counters
  arm64: Remove unused cpu_name ascii in arch/arm64/mm/proc.S
  arm64: dts: Reserve the memory used for secondary CPU release address
  arm64: check for number of arguments in syscall_get/set_arguments()
  arm64: fix possible invalid FPSIMD initialization state
  ...

Change-Id: Ia0e5d71b536ab49ec3a1179d59238c05bdd03106
Signed-off-by: Ian Maund <imaund@codeaurora.org>
2014-03-24 14:28:34 -07:00
Bart Van Assche d2f5933432 timer: Fix jiffies wrap behavior of round_jiffies_common()
commit 9e04d3804d3ac97d8c03a41d78d0f0674b5d01e1 upstream.

Direct compare of jiffies related values does not work in the wrap
around case. Replace it with time_is_after_jiffies().

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: http://lkml.kernel.org/r/519BC066.5080600@acm.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-21 18:21:31 -07:00
Badhri Jagan Sridharan 77202e52b3 trace: Modify timer_start and irq_handler_entry trace events.
The timer_start event now shows whether the timer is
deferrable in case of a low-res timer. The debug_activate
function now includes deferrable flag while calling
trace_timer_start event. irq_handler_entry
event includes the ISR function in the trace event.

Change-Id: Ia2eeb4fa0fae34b301964144dad8bcef7632487c
Signed-off-by: Badhri Jagan Sridharan <badhris@codeaurora.org>
(cherry picked from commit a2cd6eaf5deaa40098eb6b692797519bc173381e)
2013-07-08 05:51:40 -07:00
Linus Torvalds cc51bf6e6d Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:

 - Cure for not using zalloc in the first place, which leads to random
   crashes with CPUMASK_OFF_STACK.

 - Revert a user space visible change which broke udev

 - Add a missing cpu_online early return introduced by the new full
   dyntick conversions

 - Plug a long standing race in the timer wheel cpu hotplug code.
   Sigh...

 - Cleanup NOHZ per cpu data on cpu down to prevent stale data on cpu
   up.

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Revert ALWAYS_USE_PERSISTENT_CLOCK compile time optimizaitons
  timer: Don't reinitialize the cpu base lock during CPU_UP_PREPARE
  tick: Don't invoke tick_nohz_stop_sched_tick() if the cpu is offline
  tick: Cleanup NOHZ per cpu data on cpu down
  tick: Use zalloc_cpumask_var for allocating offstack cpumasks
2013-05-15 14:05:17 -07:00
Tirupathi Reddy 42a5cf46cd timer: Don't reinitialize the cpu base lock during CPU_UP_PREPARE
An inactive timer's base can refer to a offline cpu's base.

In the current code, cpu_base's lock is blindly reinitialized each
time a CPU is brought up. If a CPU is brought online during the period
that another thread is trying to modify an inactive timer on that CPU
with holding its timer base lock, then the lock will be reinitialized
under its feet. This leads to following SPIN_BUG().

<0> BUG: spinlock already unlocked on CPU#3, kworker/u:3/1466
<0> lock: 0xe3ebe000, .magic: dead4ead, .owner: kworker/u:3/1466, .owner_cpu: 1
<4> [<c0013dc4>] (unwind_backtrace+0x0/0x11c) from [<c026e794>] (do_raw_spin_unlock+0x40/0xcc)
<4> [<c026e794>] (do_raw_spin_unlock+0x40/0xcc) from [<c076c160>] (_raw_spin_unlock+0x8/0x30)
<4> [<c076c160>] (_raw_spin_unlock+0x8/0x30) from [<c009b858>] (mod_timer+0x294/0x310)
<4> [<c009b858>] (mod_timer+0x294/0x310) from [<c00a5e04>] (queue_delayed_work_on+0x104/0x120)
<4> [<c00a5e04>] (queue_delayed_work_on+0x104/0x120) from [<c04eae00>] (sdhci_msm_bus_voting+0x88/0x9c)
<4> [<c04eae00>] (sdhci_msm_bus_voting+0x88/0x9c) from [<c04d8780>] (sdhci_disable+0x40/0x48)
<4> [<c04d8780>] (sdhci_disable+0x40/0x48) from [<c04bf300>] (mmc_release_host+0x4c/0xb0)
<4> [<c04bf300>] (mmc_release_host+0x4c/0xb0) from [<c04c7aac>] (mmc_sd_detect+0x90/0xfc)
<4> [<c04c7aac>] (mmc_sd_detect+0x90/0xfc) from [<c04c2504>] (mmc_rescan+0x7c/0x2c4)
<4> [<c04c2504>] (mmc_rescan+0x7c/0x2c4) from [<c00a6a7c>] (process_one_work+0x27c/0x484)
<4> [<c00a6a7c>] (process_one_work+0x27c/0x484) from [<c00a6e94>] (worker_thread+0x210/0x3b0)
<4> [<c00a6e94>] (worker_thread+0x210/0x3b0) from [<c00aad9c>] (kthread+0x80/0x8c)
<4> [<c00aad9c>] (kthread+0x80/0x8c) from [<c000ea80>] (kernel_thread_exit+0x0/0x8)

As an example, this particular crash occurred when CPU #3 is executing
mod_timer() on an inactive timer whose base is refered to offlined CPU
#2.  The code locked the timer_base corresponding to CPU #2. Before it
could proceed, CPU #2 came online and reinitialized the spinlock
corresponding to its base. Thus now CPU #3 held a lock which was
reinitialized. When CPU #3 finally ended up unlocking the old cpu_base
corresponding to CPU #2, we hit the above SPIN_BUG().

CPU #0		CPU #3				       CPU #2
------		-------				       -------
.....		 ......				      <Offline>
		mod_timer()
		 lock_timer_base
		   spin_lock_irqsave(&base->lock)

cpu_up(2)	 .....				        ......
							init_timers_cpu()
....		 .....				    	spin_lock_init(&base->lock)
.....		   spin_unlock_irqrestore(&base->lock)  ......
		   <spin_bug>

Allocation of per_cpu timer vector bases is done only once under
"tvec_base_done[]" check. In the current code, spinlock_initialization
of base->lock isn't under this check. When a CPU is up each time the
base lock is reinitialized. Move base spinlock initialization under
the check.

Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1368520142-4136-1-git-send-email-tirupath@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14 17:59:18 +02:00
Linus Torvalds 534c97b095 Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull 'full dynticks' support from Ingo Molnar:
 "This tree from Frederic Weisbecker adds a new, (exciting! :-) core
  kernel feature to the timer and scheduler subsystems: 'full dynticks',
  or CONFIG_NO_HZ_FULL=y.

  This feature extends the nohz variable-size timer tick feature from
  idle to busy CPUs (running at most one task) as well, potentially
  reducing the number of timer interrupts significantly.

  This feature got motivated by real-time folks and the -rt tree, but
  the general utility and motivation of full-dynticks runs wider than
  that:

   - HPC workloads get faster: CPUs running a single task should be able
     to utilize a maximum amount of CPU power.  A periodic timer tick at
     HZ=1000 can cause a constant overhead of up to 1.0%.  This feature
     removes that overhead - and speeds up the system by 0.5%-1.0% on
     typical distro configs even on modern systems.

   - Real-time workload latency reduction: CPUs running critical tasks
     should experience as little jitter as possible.  The last remaining
     source of kernel-related jitter was the periodic timer tick.

   - A single task executing on a CPU is a pretty common situation,
     especially with an increasing number of cores/CPUs, so this feature
     helps desktop and mobile workloads as well.

  The cost of the feature is mainly related to increased timer
  reprogramming overhead when a CPU switches its tick period, and thus
  slightly longer to-idle and from-idle latency.

  Configuration-wise a third mode of operation is added to the existing
  two NOHZ kconfig modes:

   - CONFIG_HZ_PERIODIC: [formerly !CONFIG_NO_HZ], now explicitly named
     as a config option.  This is the traditional Linux periodic tick
     design: there's a HZ tick going on all the time, regardless of
     whether a CPU is idle or not.

   - CONFIG_NO_HZ_IDLE: [formerly CONFIG_NO_HZ=y], this turns off the
     periodic tick when a CPU enters idle mode.

   - CONFIG_NO_HZ_FULL: this new mode, in addition to turning off the
     tick when a CPU is idle, also slows the tick down to 1 Hz (one
     timer interrupt per second) when only a single task is running on a
     CPU.

  The .config behavior is compatible: existing !CONFIG_NO_HZ and
  CONFIG_NO_HZ=y settings get translated to the new values, without the
  user having to configure anything.  CONFIG_NO_HZ_FULL is turned off by
  default.

  This feature is based on a lot of infrastructure work that has been
  steadily going upstream in the last 2-3 cycles: related RCU support
  and non-periodic cputime support in particular is upstream already.

  This tree adds the final pieces and activates the feature.  The pull
  request is marked RFC because:

   - it's marked 64-bit only at the moment - the 32-bit support patch is
     small but did not get ready in time.

   - it has a number of fresh commits that came in after the merge
     window.  The overwhelming majority of commits are from before the
     merge window, but still some aspects of the tree are fresh and so I
     marked it RFC.

   - it's a pretty wide-reaching feature with lots of effects - and
     while the components have been in testing for some time, the full
     combination is still not very widely used.  That it's default-off
     should reduce its regression abilities and obviously there are no
     known regressions with CONFIG_NO_HZ_FULL=y enabled either.

   - the feature is not completely idempotent: there is no 100%
     equivalent replacement for a periodic scheduler/timer tick.  In
     particular there's ongoing work to map out and reduce its effects
     on scheduler load-balancing and statistics.  This should not impact
     correctness though, there are no known regressions related to this
     feature at this point.

   - it's a pretty ambitious feature that with time will likely be
     enabled by most Linux distros, and we'd like you to make input on
     its design/implementation, if you dislike some aspect we missed.
     Without flaming us to crisp! :-)

  Future plans:

   - there's ongoing work to reduce 1Hz to 0Hz, to essentially shut off
     the periodic tick altogether when there's a single busy task on a
     CPU.  We'd first like 1 Hz to be exposed more widely before we go
     for the 0 Hz target though.

   - once we reach 0 Hz we can remove the periodic tick assumption from
     nr_running>=2 as well, by essentially interrupting busy tasks only
     as frequently as the sched_latency constraints require us to do -
     once every 4-40 msecs, depending on nr_running.

  I am personally leaning towards biting the bullet and doing this in
  v3.10, like the -rt tree this effort has been going on for too long -
  but the final word is up to you as usual.

  More technical details can be found in Documentation/timers/NO_HZ.txt"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  sched: Keep at least 1 tick per second for active dynticks tasks
  rcu: Fix full dynticks' dependency on wide RCU nocb mode
  nohz: Protect smp_processor_id() in tick_nohz_task_switch()
  nohz_full: Add documentation.
  cputime_nsecs: use math64.h for nsec resolution conversion helpers
  nohz: Select VIRT_CPU_ACCOUNTING_GEN from full dynticks config
  nohz: Reduce overhead under high-freq idling patterns
  nohz: Remove full dynticks' superfluous dependency on RCU tree
  nohz: Fix unavailable tick_stop tracepoint in dynticks idle
  nohz: Add basic tracing
  nohz: Select wide RCU nocb for full dynticks
  nohz: Disable the tick when irq resume in full dynticks CPU
  nohz: Re-evaluate the tick for the new task after a context switch
  nohz: Prepare to stop the tick on irq exit
  nohz: Implement full dynticks kick
  nohz: Re-evaluate the tick from the scheduler IPI
  sched: New helper to prevent from stopping the tick in full dynticks
  sched: Kick full dynticks CPU that have more than one task enqueued.
  perf: New helper to prevent full dynticks CPUs from stopping tick
  perf: Kick full dynticks CPU if events rotation is needed
  ...
2013-05-05 13:23:27 -07:00
Stephen Rothwell 4a22f16636 kernel/timer.c: move some non timer related syscalls to kernel/sys.c
Andrew Morton noted:

	akpm3:/usr/src/25> grep SYSCALL kernel/timer.c
	SYSCALL_DEFINE1(alarm, unsigned int, seconds)
	SYSCALL_DEFINE0(getpid)
	SYSCALL_DEFINE0(getppid)
	SYSCALL_DEFINE0(getuid)
	SYSCALL_DEFINE0(geteuid)
	SYSCALL_DEFINE0(getgid)
	SYSCALL_DEFINE0(getegid)
	SYSCALL_DEFINE0(gettid)
	SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
	COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)

	Only one of those should be in kernel/timer.c.  Who wrote this thing?

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:03 -07:00
Stephen Rothwell 1043f65a57 kernel/timer.c: convert compat_sys_sysinfo to COMPAT_SYSCALL_DEFINE
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:03 -07:00
Stephen Rothwell 1a0df59444 kernel/compat.c: make do_sysinfo() static
The only use outside of kernel/timer.c was in kernel/compat.c, so move
compat_sys_sysinfo() next to sys_sysinfo() in kernel/timer.c.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:03 -07:00
Frederic Weisbecker 3451d0243c nohz: Rename CONFIG_NO_HZ to CONFIG_NO_HZ_COMMON
We are planning to convert the dynticks Kconfig options layout
into a choice menu. The user must be able to easily pick
any of the following implementations: constant periodic tick,
idle dynticks, full dynticks.

As this implies a mutual exclusion, the two dynticks implementions
need to converge on the selection of a common Kconfig option in order
to ease the sharing of a common infrastructure.

It would thus seem pretty natural to reuse CONFIG_NO_HZ to
that end. It already implements all the idle dynticks code
and the full dynticks depends on all that code for now.
So ideally the choice menu would propose CONFIG_NO_HZ_IDLE and
CONFIG_NO_HZ_EXTENDED then both would select CONFIG_NO_HZ.

On the other hand we want to stay backward compatible: if
CONFIG_NO_HZ is set in an older config file, we want to
enable CONFIG_NO_HZ_IDLE by default.

But we can't afford both at the same time or we run into
a circular dependency:

1) CONFIG_NO_HZ_IDLE and CONFIG_NO_HZ_EXTENDED both select
   CONFIG_NO_HZ
2) If CONFIG_NO_HZ is set, we default to CONFIG_NO_HZ_IDLE

We might be able to support that from Kconfig/Kbuild but it
may not be wise to introduce such a confusing behaviour.

So to solve this, create a new CONFIG_NO_HZ_COMMON option
which gathers the common code between idle and full dynticks
(that common code for now is simply the idle dynticks code)
and select it from their referring Kconfig.

Then we'll later create CONFIG_NO_HZ_IDLE and map CONFIG_NO_HZ
to it for backward compatibility.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.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>
2013-04-03 13:56:03 +02:00
Frederic Weisbecker 1c20091e77 nohz: Wake up full dynticks CPUs when a timer gets enqueued
Wake up a CPU when a timer list timer is enqueued there and
the target is part of the full dynticks range. Sending an IPI
to it makes it reconsidering the next timer to program on top
of recent updates.

This may later be improved by checking if the tick is really
stopped on the target. This would need some careful
synchronization though. So deal with such optimization later
and start simple.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.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>
2013-03-21 15:55:59 +01:00
Linus Torvalds d652e1eb8e Merge branch 'sched-core-for-linus' of 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.
2013-02-19 18:19:48 -08:00
Clark Williams cf4aebc292 sched: Move sched.h sysctl bits into separate header
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>
2013-02-07 20:50:54 +01:00
Frederic Weisbecker 74876a98a8 printk: Wake up klogd using irq_work
klogd is woken up asynchronously from the tick in order
to do it safely.

However if printk is called when the tick is stopped, the reader
won't be woken up until the next interrupt, which might not fire
for a while. As a result, the user may miss some message.

To fix this, lets implement the printk tick using a lazy irq work.
This subsystem takes care of the timer tick state and can
fix up accordingly.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-11-18 01:01:49 +01:00
Hildner, Christian 26cff4e2aa timers: Fix endless looping between cascade() and internal_add_timer()
Adding two (or more) timers with large values for "expires" (they have
to reside within tv5 in the same list) leads to endless looping
between cascade() and internal_add_timer() in case CONFIG_BASE_SMALL
is one and jiffies are crossing the value 1 << 18. The bug was
introduced between 2.6.11 and 2.6.12 (and survived for quite some
time).

This patch ensures that when cascade() is called timers within tv5 are
not added endlessly to their own list again, instead they are added to
the next lower tv level tv4 (as expected).

Signed-off-by: Christian Hildner <christian.hildner@siemens.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Link: http://lkml.kernel.org/r/98673C87CB31274881CFFE0B65ECC87B0F5FC1963E@DEFTHW99EA4MSX.ww902.siemens.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
2012-10-09 21:27:14 +02:00
Thomas Gleixner db8c246937 Merge branch 'fortglx/3.7/time' of git://git.linaro.org/people/jstultz/linux into timers/core 2012-10-09 21:20:05 +02:00
Tejun Heo c5f66e99b7 timer: Implement TIMER_IRQSAFE
Timer internals are protected with irq-safe locks but timer execution
isn't, so a timer being dequeued for execution and its execution
aren't atomic against IRQs.  This makes it impossible to wait for its
completion from IRQ handlers and difficult to shoot down a timer from
IRQ handlers.

This issue caused some issues for delayed_work interface.  Because
there's no way to reliably shoot down delayed_work->timer from IRQ
handlers, __cancel_delayed_work() can't share the logic to steal the
target delayed_work with cancel_delayed_work_sync(), and can only
steal delayed_works which are on queued on timer.  Similarly, the
pending mod_delayed_work() can't be used from IRQ handlers.

This patch adds a new timer flag TIMER_IRQSAFE, which makes the timer
to be executed without enabling IRQ after dequeueing such that its
dequeueing and execution are atomic against IRQ handlers.

This makes it safe to wait for the timer's completion from IRQ
handlers, for example, using del_timer_sync().  It can never be
executing on the local CPU and if executing on other CPUs it won't be
interrupted until done.

This will enable simplifying delayed_work cancel/mod interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1344449428-24962-5-git-send-email-tj@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21 16:28:31 +02:00
Tejun Heo fc683995a6 timer: Clean up timer initializers
Over time, timer initializers became messy with unnecessarily
duplicated code which are inconsistently spread across timer.h and
timer.c.

This patch cleans up timer initializers.

* timer.c::__init_timer() is renamed to do_init_timer().

* __TIMER_INITIALIZER() added.  It takes @flags and all initializers
  are wrappers around it.

* init_timer[_on_stack]_key() now take @flags.

* __init_timer[_on_stack]() added.  They take @flags and all init
  macros are wrappers around them.

* __setup_timer[_on_stack]() added.  It uses __init_timer() and takes
  @flags.  All setup macros are wrappers around the two.

Note that this patch doesn't add missing init/setup combinations -
e.g. init_timer_deferrable_on_stack().  Adding missing ones is
trivial.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1344449428-24962-4-git-send-email-tj@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21 16:28:30 +02:00
Tejun Heo e52b1db37b timer: Generalize timer->base flags handling
To prepare for addition of another flag, generalize timer->base flags
handling.

* Rename from TBASE_*_FLAG to TIMER_* and make them LU constants.

* Define and use TIMER_FLAG_MASK for flags masking so that multiple
  flags can be handled correctly.

* Don't dereference timer->base directly even if
  !tbase_get_deferrable().  All two such places are already passed in
  @base, so use it instead.

* Make sure tvec_base's alignment is large enough for timer->base
  flags using BUILD_BUG_ON().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1344449428-24962-2-git-send-email-tj@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-21 16:28:30 +02:00
Al Viro be53db6e4e alpha: take a bunch of syscalls into osf_sys.c
New helper: current_thread_info().  Allows to do a bunch of odd syscalls
in C. While we are at it, there had never been a reason to do
osf_getpriority() in assembler.  We also get "namespace"-aware (read:
consistent with getuid(2), etc.) behaviour from getx?id() syscalls now.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Michael Cree <mcree@orcon.net.nz>
Acked-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-19 08:41:19 -07:00
Thomas Gleixner e40468a548 timers: Improve get_next_timer_interrupt()
Gilad reported at

 http://lkml.kernel.org/r/1336056962-10465-2-git-send-email-gilad@benyossef.com

"Current timer code fails to correctly return a value meaning that
 there is no future timer event, with the result that the timer keeps
 getting re-armed in HZ one shot mode even when we could turn it off,
 generating unneeded interrupts.

 What is happening is that when __next_timer_interrupt() wishes
 to return a value that signifies "there is no future timer
 event", it returns (base->timer_jiffies + NEXT_TIMER_MAX_DELTA).

 However, the code in tick_nohz_stop_sched_tick(), which called
 __next_timer_interrupt() via get_next_timer_interrupt(),
 compares the return value to (last_jiffies + NEXT_TIMER_MAX_DELTA)
 to see if the timer needs to be re-armed.

 base->timer_jiffies != last_jiffies and so tick_nohz_stop_sched_tick()
 interperts the return value as indication that there is a distant
 future event 12 days from now and programs the timer to fire next
 after KTIME_MAX nsecs instead of avoiding to arm it. This ends up
 causing a needless interrupt once every KTIME_MAX nsecs."

Fix this by using the new active timer accounting. This avoids scans
when no active timer is enqueued completely, so we don't have to rely
on base->timer_next and base->timer_jiffies anymore.

Reported-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20120525214819.317535385@linutronix.de
2012-06-06 13:49:02 +02:00
Thomas Gleixner 99d5f3aac6 timers: Add accounting of non deferrable timers
The code in get_next_timer_interrupt() is suboptimal as it has to run
through the cascade to find the next expiring timer. On a completely
idle core we should only do that when there is an active timer
enqueued and base->next_timer does not give us a fast answer.

Add accounting of the active timers to the now consolidated
attach/detach code. I deliberately avoided sanity checks because the
code is fully symetric and any fiddling with timers w/o using the API
functions will lead to cute explosions anyway. ulong is big enough
even on 32bit and if we really run into the situation to have more
than 1<<32 timers enqueued there, then we are definitely not in a
state to go idle and run through that code.

This allows us to fix another shortcoming of get_next_timer_interrupt().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20120525214819.236377028@linutronix.de
2012-06-06 13:49:01 +02:00
Thomas Gleixner facbb4a7ef timers: Consolidate base->next_timer update
Another bunch of mindlessly copied code. All callers of
internal_add_timer() except the recascading code updates
base->next_timer.

Move this into internal_add_timer() and let the cascading code call
__internal_add_timer().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20120525214819.189946224@linutronix.de
2012-06-06 13:49:01 +02:00
Thomas Gleixner ec44bc7acc timers: Create detach_if_pending() and use it
Most callers of detach_timer() have the same pattern around
them. Check whether the timer is pending and eventually updating
base->next_timer.

Create detach_if_pending() and replace the duplicated code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20120525214819.131246037@linutronix.de
2012-06-06 13:49:01 +02:00
Linus Torvalds 644473e9c6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace enhancements from Eric Biederman:
 "This is a course correction for the user namespace, so that we can
  reach an inexpensive, maintainable, and reasonably complete
  implementation.

  Highlights:
   - Config guards make it impossible to enable the user namespace and
     code that has not been converted to be user namespace safe.

   - Use of the new kuid_t type ensures the if you somehow get past the
     config guards the kernel will encounter type errors if you enable
     user namespaces and attempt to compile in code whose permission
     checks have not been updated to be user namespace safe.

   - All uids from child user namespaces are mapped into the initial
     user namespace before they are processed.  Removing the need to add
     an additional check to see if the user namespace of the compared
     uids remains the same.

   - With the user namespaces compiled out the performance is as good or
     better than it is today.

   - For most operations absolutely nothing changes performance or
     operationally with the user namespace enabled.

   - The worst case performance I could come up with was timing 1
     billion cache cold stat operations with the user namespace code
     enabled.  This went from 156s to 164s on my laptop (or 156ns to
     164ns per stat operation).

   - (uid_t)-1 and (gid_t)-1 are reserved as an internal error value.
     Most uid/gid setting system calls treat these value specially
     anyway so attempting to use -1 as a uid would likely cause
     entertaining failures in userspace.

   - If setuid is called with a uid that can not be mapped setuid fails.
     I have looked at sendmail, login, ssh and every other program I
     could think of that would call setuid and they all check for and
     handle the case where setuid fails.

   - If stat or a similar system call is called from a context in which
     we can not map a uid we lie and return overflowuid.  The LFS
     experience suggests not lying and returning an error code might be
     better, but the historical precedent with uids is different and I
     can not think of anything that would break by lying about a uid we
     can't map.

   - Capabilities are localized to the current user namespace making it
     safe to give the initial user in a user namespace all capabilities.

  My git tree covers all of the modifications needed to convert the core
  kernel and enough changes to make a system bootable to runlevel 1."

Fix up trivial conflicts due to nearby independent changes in fs/stat.c

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits)
  userns:  Silence silly gcc warning.
  cred: use correct cred accessor with regards to rcu read lock
  userns: Convert the move_pages, and migrate_pages permission checks to use uid_eq
  userns: Convert cgroup permission checks to use uid_eq
  userns: Convert tmpfs to use kuid and kgid where appropriate
  userns: Convert sysfs to use kgid/kuid where appropriate
  userns: Convert sysctl permission checks to use kuid and kgids.
  userns: Convert proc to use kuid/kgid where appropriate
  userns: Convert ext4 to user kuid/kgid where appropriate
  userns: Convert ext3 to use kuid/kgid where appropriate
  userns: Convert ext2 to use kuid/kgid where appropriate.
  userns: Convert devpts to use kuid/kgid where appropriate
  userns: Convert binary formats to use kuid/kgid where appropriate
  userns: Add negative depends on entries to avoid building code that is userns unsafe
  userns: signal remove unnecessary map_cred_ns
  userns: Teach inode_capable to understand inodes whose uids map to other namespaces.
  userns: Fail exec for suid and sgid binaries with ids outside our user namespace.
  userns: Convert stat to return values mapped from kuids and kgids
  userns: Convert user specfied uids and gids in chown into kuids and kgid
  userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs
  ...
2012-05-23 17:42:39 -07:00
Linus Torvalds c54894cd46 Merge branch 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue changes from Tejun Heo:
 "Nothing exciting.  Most are updates to debug stuff and related fixes.
  Two not-too-critical bugs are fixed - WARN_ON() triggering spurious
  during cpu offlining and unlikely lockdep related oops."

* 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  lockdep: fix oops in processing workqueue
  workqueue: skip nr_running sanity check in worker_enter_idle() if trustee is active
  workqueue: Catch more locking problems with flush_work()
  workqueue: change BUG_ON() to WARN_ON()
  trace: Remove unused workqueue tracer
2012-05-22 17:36:56 -07:00
Peter Zijlstra 4d82a1debb lockdep: fix oops in processing workqueue
Under memory load, on x86_64, with lockdep enabled, the workqueue's
process_one_work() has been seen to oops in __lock_acquire(), barfing
on a 0xffffffff00000000 pointer in the lockdep_map's class_cache[].

Because it's permissible to free a work_struct from its callout function,
the map used is an onstack copy of the map given in the work_struct: and
that copy is made without any locking.

Surprisingly, gcc (4.5.1 in Hugh's case) uses "rep movsl" rather than
"rep movsq" for that structure copy: which might race with a workqueue
user's wait_on_work() doing lock_map_acquire() on the source of the
copy, putting a pointer into the class_cache[], but only in time for
the top half of that pointer to be copied to the destination map.

Boom when process_one_work() subsequently does lock_map_acquire()
on its onstack copy of the lockdep_map.

Fix this, and a similar instance in call_timer_fn(), with a
lockdep_copy_map() function which additionally NULLs the class_cache[].

Note: this oops was actually seen on 3.4-next, where flush_work() newly
does the racing lock_map_acquire(); but Tejun points out that 3.4 and
earlier are already vulnerable to the same through wait_on_work().

* Patch orginally from Peter.  Hugh modified it a bit and wrote the
  description.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Reported-by: Hugh Dickins <hughd@google.com>
LKML-Reference: <alpine.LSU.2.00.1205070951170.1544@eggly.anvils>
Signed-off-by: Tejun Heo <tj@kernel.org>
2012-05-15 08:08:31 -07:00
Eric W. Biederman a29c33f4e5 userns: Convert setting and getting uid and gid system calls to use kuid and kgid
Convert setregid, setgid, setreuid, setuid,
setresuid, getresuid, setresgid, getresgid, setfsuid, setfsgid,
getuid, geteuid, getgid, getegid,
waitpid, waitid, wait4.

Convert userspace uids and gids into kuids and kgids before
being placed on struct cred.  Convert struct cred kuids and
kgids into userspace uids and gids when returning them.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-05-03 03:28:41 -07:00
Paul E. McKenney 048a0e8f5e timer: Fix mod_timer_pinned() header comment
The mod_timer_pinned() header comment states that it prevents timers
from being migrated to a different CPU.  This is not the case, instead,
it ensures that the timer is posted to the current CPU, but does nothing
to prevent CPU-hotplug operations from migrating the timer.

This commit therefore brings the comment header into alignment with
reality.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
2012-04-26 12:28:03 -07:00
Linus Torvalds 8c717b72de Merge branch 'core-debugobjects-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-debugobjects-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timer: Use debugobjects to catch deletion of uninitialized timers
  timer: Setup uninitialized timer with a stub callback
  debugobjects: Extend to assert that an object is initialized
  debugobjects: Be smarter about static objects
2012-01-06 07:53:34 -08:00
Mandeep Singh Baines 031af165b1 sys_getppid: add missing rcu_dereference
In order to safely dereference current->real_parent inside an
rcu_read_lock, we need an rcu_dereference.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:29 -08:00
Christine Chan dc4218bd0f timer: Use debugobjects to catch deletion of uninitialized timers
del_timer_sync() calls debug_object_assert_init() to assert that
a timer has been initialized before calling lock_timer_base().
lock_timer_base() would spin forever on a NULL(uninit-ed) base.
The check is added to del_timer() to prevent silent failure, even
though it would not get stuck in an infinite loop.

[ sboyd@codeaurora.org: Remove WARN, intialize timer function]

Signed-off-by: Christine Chan <cschan@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1320724108-20788-4-git-send-email-sboyd@codeaurora.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-11-23 18:49:23 +01:00
Stephen Boyd fb16b8cf0b timer: Setup uninitialized timer with a stub callback
Remove the WARN_ON() in timer_fixup_activate() as we now get the
debugobjects printout in the debugobjects activate check.

We also assign a dummy timer callback so that if the timer is
actually set to fire we don't oops.

[ tglx@linutronix.de: Split out the debugobjects vs. the timer change ]

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Christine Chan <cschan@codeaurora.org>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1320724108-20788-2-git-send-email-sboyd@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-11-23 18:49:23 +01:00
Paul Gortmaker 9984de1a5a kernel: Map most files to use export.h instead of module.h
The changed files were only including linux/module.h for the
EXPORT_SYMBOL infrastructure, and nothing else.  Revector them
onto the isolated export header for faster compile times.

Nothing to see here but a whole lot of instances of:

  -#include <linux/module.h>
  +#include <linux/export.h>

This commit is only changing the kernel dir; next targets
will probably be mm, fs, the arch dirs, etc.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:12 -04:00
Sebastian Andrzej Siewior 1c3cc11602 timers: Consider slack value in mod_timer()
There is an optimization which does not update the timer if the timer
was pending and the expiration time was unchanged.

Since commit 3bbb9ec9 ("timers: Introduce the concept of timer slack
for legacy timers") this optimization is no longer applied for timers
where the expiration time got extended due to the slack value. So we
need to check again after the expiration time might have been updated.

[ tglx: Made it a single check by applying slack first and sorting
  out the slack = 0 value (all timeouts < 256 jiffies) early ]

Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Link: http://lkml.kernel.org/r/20110521105828.GA29442@Chamillionaire.breakpoint.cc
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-06-03 15:02:32 +02:00
Linus Torvalds 420c1c572d Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (62 commits)
  posix-clocks: Check write permissions in posix syscalls
  hrtimer: Remove empty hrtimer_init_hres_timer()
  hrtimer: Update hrtimer->state documentation
  hrtimer: Update base[CLOCK_BOOTTIME].offset correctly
  timers: Export CLOCK_BOOTTIME via the posix timers interface
  timers: Add CLOCK_BOOTTIME hrtimer base
  time: Extend get_xtime_and_monotonic_offset() to also return sleep
  time: Introduce get_monotonic_boottime and ktime_get_boottime
  hrtimers: extend hrtimer base code to handle more then 2 clockids
  ntp: Remove redundant and incorrect parameter check
  mn10300: Switch do_timer() to xtimer_update()
  posix clocks: Introduce dynamic clocks
  posix-timers: Cleanup namespace
  posix-timers: Add support for fd based clocks
  x86: Add clock_adjtime for x86
  posix-timers: Introduce a syscall for clock tuning.
  time: Splitout compat timex accessors
  ntp: Add ADJ_SETOFFSET mode bit
  time: Introduce timekeeping_inject_offset
  posix-timer: Update comment
  ...

Fix up new system-call-related conflicts in
	arch/x86/ia32/ia32entry.S
	arch/x86/include/asm/unistd_32.h
	arch/x86/include/asm/unistd_64.h
	arch/x86/kernel/syscall_table_32.S
(name_to_handle_at()/open_by_handle_at() vs clock_adjtime()), and some
due to movement of get_jiffies_64() in:
	kernel/time.c
2011-03-15 18:53:35 -07:00
Linus Torvalds 0586bed3e8 Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rtmutex: tester: Remove the remaining BKL leftovers
  lockdep/timers: Explain in detail the locking problems del_timer_sync() may cause
  rtmutex: Simplify PI algorithm and make highest prio task get lock
  rwsem: Remove redundant asmregparm annotation
  rwsem: Move duplicate function prototypes to linux/rwsem.h
  rwsem: Unify the duplicate rwsem_is_locked() inlines
  rwsem: Move duplicate init macros and functions to linux/rwsem.h
  rwsem: Move duplicate struct rwsem declaration to linux/rwsem.h
  x86: Cleanup rwsem_count_t typedef
  rwsem: Cleanup includes
  locking: Remove deprecated lock initializers
  cred: Replace deprecated spinlock initialization
  kthread: Replace deprecated spinlock initialization
  xtensa: Replace deprecated spinlock initialization
  um: Replace deprecated spinlock initialization
  sparc: Replace deprecated spinlock initialization
  mips: Replace deprecated spinlock initialization
  cris: Replace deprecated spinlock initialization
  alpha: Replace deprecated spinlock initialization
  rtmutex-tester: Remove BKL tests
2011-03-15 18:28:30 -07:00
Stanislaw Gruszka 9977728840 debugobjects: Add hint for better object identification
In complex subsystems like mac80211 structures can contain several
timers and work structs, so identifying a specific instance from the
call trace and object type output of debugobjects can be hard.

Allow the subsystems which support debugobjects to provide a hint
function. This function returns a pointer to a kernel address
(preferrably the objects callback function) which is printed along
with the debugobjects type.

Add hint methods for timer_list, work_struct and hrtimer.

[ tglx: Massaged changelog, made it compile ]

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
LKML-Reference: <20110307085809.GA9334@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-08 16:10:38 +01:00
Steven Rostedt 48228f7b47 lockdep/timers: Explain in detail the locking problems del_timer_sync() may cause
Twice I had to explain the output about why lockdep gives an error with
locks in IRQ context and with del_timer_sync(). Might as well write it
up and place it in the comments above the code in del_timer_sync().
Perhaps the next time this lockdep dump triggers people will understand
the issues.

It is a ticky issue and very subtle, explaining it in detail in the code
may help others understand the issue when they stumble upon the bug
again.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1297186794.23343.19.camel@gandalf.stny.rr.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-16 13:35:08 +01:00
Peter Zijlstra 7ff207928e Revert "lockdep, timer: Fix del_timer_sync() annotation"
Both attempts at trying to allow softirq usage for
del_timer_sync() failed (produced bogus warnings),
so revert the commit for this release:

  f266a5110d45: lockdep, timer: Fix del_timer_sync() annotation

and try again later.

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Yong Zhang <yong.zhang0@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <1297174680.13327.107.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-08 16:18:39 +01:00
Peter Zijlstra f266a5110d lockdep, timer: Fix del_timer_sync() annotation
Calling local_bh_enable() will want to actually start processing
softirqs, which isn't a good idea since this can get called with IRQs
disabled.

Cure this by using _local_bh_enable() which doesn't start processing
softirqs, and use raw_local_irq_save() to avoid any softirqs from
happening without letting lockdep think IRQs are in fact disabled.

Reported-by: Nick Bowler <nbowler@elliptictech.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Yong Zhang <yong.zhang0@gmail.com>
LKML-Reference: <20110203141548.039540914@chello.nl>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-04 10:31:22 +01:00
Torben Hohn 871cf1e5f2 time: Move do_timer() to kernel/time/timekeeping.c
do_timer() is primary timekeeping related. calc_global_load() is
called from do_timer() as well, but that's more for historical
reasons.

[ tglx: Fixed up the calc_global_load() reject andmassaged changelog ]

Signed-off-by: Torben Hohn <torbenh@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: johnstul@us.ibm.com
Cc: yong.zhang0@gmail.com
Cc: hch@infradead.org
LKML-Reference: <20110127145855.23248.56933.stgit@localhost>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-31 14:55:41 +01:00
Linus Torvalds dda5f0a372 Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  MAINTAINERS: Update timer related entries
  timers: Use this_cpu_read
  timerqueue: Make timerqueue_getnext() static inline
  hrtimer: fix timerqueue conversion flub
  hrtimers: Convert hrtimers to use timerlist infrastructure
  timers: Fixup allmodconfig build issue
  timers: Rename timerlist infrastructure to timerqueue
  timers: Introduce timerlist infrastructure.
  hrtimer: Remove stale comment on curr_timer
  timer: Warn when del_timer_sync() is called in hardirq context
  timer: Del_timer_sync() can be used in softirq context
  timer: Make try_to_del_timer_sync() the same on SMP and UP
  posix-timers: Annotate lock_timer()
  timer: Permit statically-declared work with deferrable timers
  time: Use ARRAY_SIZE macro in timecompare.c
  timer: Initialize the field slack of timer_list
  timer_list: Remove alignment padding on 64 bit when CONFIG_TIMER_STATS
  time: Compensate for rounding on odd-frequency clocksources

Fix up trivial conflict in MAINTAINERS
2011-01-06 10:42:43 -08:00