1. 25 2月, 2010 4 次提交
    • P
      rcu: Disable lockdep checking in RCU list-traversal primitives · 3120438a
      Paul E. McKenney 提交于
      The theory is that use of bare rcu_dereference() is more prone
      to error than use of the RCU list-traversal primitives.
      Therefore, disable lockdep RCU read-side critical-section
      checking in these primitives for the time being.  Once all of
      the rcu_dereference() uses have been dealt with, it may be time
      to re-enable lockdep checking for the RCU list-traversal
      primitives.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-4-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      3120438a
    • P
      rcu: Integrate rcu_dereference_check() message into lockdep · 0632eb3d
      Paul E. McKenney 提交于
      Make rcu_dereference_check() print the list of held locks in
      addition to the stack dump to ease debugging.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-3-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      0632eb3d
    • P
      rcu: Add lockdep-enabled variants of rcu_dereference() · c26d34a5
      Paul E. McKenney 提交于
      Make rcu_dereference() check for being in an RCU read-side
      critical section, and create rcu_dereference_bh(),
      rcu_dereference_sched(), and srcu_dereference() to check for the
      other flavors of RCU.  Also create rcu_dereference_raw() to
      avoid checking, and make rcu_dereference_check() use
      rcu_dereference_raw().
      Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-2-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      c26d34a5
    • P
      rcu: Introduce lockdep-based checking to RCU read-side primitives · 632ee200
      Paul E. McKenney 提交于
      Inspection is proving insufficient to catch all RCU misuses,
      which is understandable given that rcu_dereference() might be
      protected by any of four different flavors of RCU (RCU, RCU-bh,
      RCU-sched, and SRCU), and might also/instead be protected by any
      of a number of locking primitives. It is therefore time to
      enlist the aid of lockdep.
      
      This set of patches is inspired by earlier work by Peter
      Zijlstra and Thomas Gleixner, and takes the following approach:
      
      o	Set up separate lockdep classes for RCU, RCU-bh, and RCU-sched.
      
      o	Set up separate lockdep classes for each instance of SRCU.
      
      o	Create primitives that check for being in an RCU read-side
      	critical section.  These return exact answers if lockdep is
      	fully enabled, but if unsure, report being in an RCU read-side
      	critical section.  (We want to avoid false positives!)
      	The primitives are:
      
      	For RCU: rcu_read_lock_held(void)
      
      	For RCU-bh: rcu_read_lock_bh_held(void)
      
      	For RCU-sched: rcu_read_lock_sched_held(void)
      
      	For SRCU: srcu_read_lock_held(struct srcu_struct *sp)
      
      o	Add rcu_dereference_check(), which takes a second argument
      	in which one places a boolean expression based on the above
      	primitives and/or lockdep_is_held().
      
      o	A new kernel configuration parameter, CONFIG_PROVE_RCU, enables
      	rcu_dereference_check().  This depends on CONFIG_PROVE_LOCKING,
      	and should be quite helpful during the transition period while
      	CONFIG_PROVE_RCU-unaware patches are in flight.
      
      The existing rcu_dereference() primitive does no checking, but
      upcoming patches will change that.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-1-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      632ee200
  2. 23 2月, 2010 1 次提交
  3. 20 2月, 2010 1 次提交
  4. 19 2月, 2010 1 次提交
  5. 18 2月, 2010 1 次提交
    • M
      Input: add KEY_RFKILL · 3b77fd8e
      Matthew Garrett 提交于
      Most laptops have keys that are intended to toggle all device state, not
      just wifi. These are currently generally mapped to KEY_WLAN. As a result,
      rfkill will only kill or enable wifi in response to the key press. This
      confuses users and can make it difficult for them to enable bluetooth
      and wwan devices.
      
      This patch adds a new keycode, KEY_RFKILL. It indicates that the system
      should toggle the state of all rfkillable devices.
      Signed-off-by: NMatthew Garrett <mjg@redhat.com>
      Acked-by: NMarcel Holtmann <marcel@holtmann.org>
      Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
      3b77fd8e
  6. 17 2月, 2010 1 次提交
  7. 07 2月, 2010 2 次提交
  8. 05 2月, 2010 1 次提交
  9. 04 2月, 2010 2 次提交
  10. 03 2月, 2010 1 次提交
    • E
      connector: Delete buggy notification code. · f98bfbd7
      Evgeniy Polyakov 提交于
      On Tue, Feb 02, 2010 at 02:57:14PM -0800, Greg KH (gregkh@suse.de) wrote:
      > > There are at least two ways to fix it: using a big cannon and a small
      > > one. The former way is to disable notification registration, since it is
      > > not used by anyone at all. Second way is to check whether calling
      > > process is root and its destination group is -1 (kind of priveledged
      > > one) before command is dispatched to workqueue.
      > 
      > Well if no one is using it, removing it makes the most sense, right?
      > 
      > No objection from me, care to make up a patch either way for this?
      
      Getting it is not used, let's drop support for notifications about
      (un)registered events from connector.
      Another option was to check credentials on receiving, but we can always
      restore it without bugs if needed, but genetlink has a wider code base
      and none complained, that userspace can not get notification when some
      other clients were (un)registered.
      
      Kudos for Sebastian Krahmer <krahmer@suse.de>, who found a bug in the
      code.
      Signed-off-by: NEvgeniy Polyakov <zbr@ioremap.net>
      Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f98bfbd7
  11. 01 2月, 2010 1 次提交
    • J
      softlockup: Add sched_clock_tick() to avoid kernel warning on kgdb resume · d6ad3e28
      Jason Wessel 提交于
      When CONFIG_HAVE_UNSTABLE_SCHED_CLOCK is set, sched_clock() gets
      the time from hardware such as the TSC on x86. In this
      configuration kgdb will report a softlock warning message on
      resuming or detaching from a debug session.
      
      Sequence of events in the problem case:
      
       1) "cpu sched clock" and "hardware time" are at 100 sec prior
          to a call to kgdb_handle_exception()
      
       2) Debugger waits in kgdb_handle_exception() for 80 sec and on
          exit the following is called ...  touch_softlockup_watchdog() -->
          __raw_get_cpu_var(touch_timestamp) = 0;
      
       3) "cpu sched clock" = 100s (it was not updated, because the
          interrupt was disabled in kgdb) but the "hardware time" = 180 sec
      
       4) The first timer interrupt after resuming from
          kgdb_handle_exception updates the watchdog from the "cpu sched clock"
      
      update_process_times() { ...  run_local_timers() -->
      softlockup_tick() --> check (touch_timestamp == 0) (it is "YES"
      here, we have set "touch_timestamp = 0" at kgdb) -->
      __touch_softlockup_watchdog() ***(A)--> reset "touch_timestamp"
      to "get_timestamp()" (Here, the "touch_timestamp" will still be
      set to 100s.)  ...
      
          scheduler_tick() ***(B)--> sched_clock_tick() (update "cpu sched
          clock" to "hardware time" = 180s) ...  }
      
       5) The Second timer interrupt handler appears to have a large
          jump and trips the softlockup warning.
      
      update_process_times() { ...  run_local_timers() -->
      softlockup_tick() --> "cpu sched clock" - "touch_timestamp" =
      180s-100s > 60s --> printk "soft lockup error messages" ...  }
      
      note: ***(A) reset "touch_timestamp" to
      "get_timestamp(this_cpu)"
      
      Why is "touch_timestamp" 100 sec, instead of 180 sec?
      
      When CONFIG_HAVE_UNSTABLE_SCHED_CLOCK is set, the call trace of
      get_timestamp() is:
      
      get_timestamp(this_cpu)
       -->cpu_clock(this_cpu)
       -->sched_clock_cpu(this_cpu)
       -->__update_sched_clock(sched_clock_data, now)
      
      The __update_sched_clock() function uses the GTOD tick value to
      create a window to normalize the "now" values.  So if "now"
      value is too big for sched_clock_data, it will be ignored.
      
      The fix is to invoke sched_clock_tick() to update "cpu sched
      clock" in order to recover from this state.  This is done by
      introducing the function touch_softlockup_watchdog_sync(). This
      allows kgdb to request that the sched clock is updated when the
      watchdog thread runs the first time after a resume from kgdb.
      
      [yong.zhang0@gmail.com: Use per cpu instead of an array]
      Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
      Signed-off-by: NDongdong Deng <Dongdong.Deng@windriver.com>
      Cc: kgdb-bugreport@lists.sourceforge.net
      Cc: peterz@infradead.org
      LKML-Reference: <1264631124-4837-2-git-send-email-jason.wessel@windriver.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d6ad3e28
  12. 30 1月, 2010 2 次提交
    • J
      perf, hw_breakpoint, kgdb: Do not take mutex for kernel debugger · 5352ae63
      Jason Wessel 提交于
      This patch fixes the regression in functionality where the
      kernel debugger and the perf API do not nicely share hw
      breakpoint reservations.
      
      The kernel debugger cannot use any mutex_lock() calls because it
      can start the kernel running from an invalid context.
      
      A mutex free version of the reservation API needed to get
      created for the kernel debugger to safely update hw breakpoint
      reservations.
      
      The possibility for a breakpoint reservation to be concurrently
      processed at the time that kgdb interrupts the system is
      improbable. Should this corner case occur the end user is
      warned, and the kernel debugger will prohibit updating the
      hardware breakpoint reservations.
      
      Any time the kernel debugger reserves a hardware breakpoint it
      will be a system wide reservation.
      Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
      Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: kgdb-bugreport@lists.sourceforge.net
      Cc: K.Prasad <prasad@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Alan Stern <stern@rowland.harvard.edu>
      Cc: torvalds@linux-foundation.org
      LKML-Reference: <1264719883-7285-3-git-send-email-jason.wessel@windriver.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      5352ae63
    • L
      Split 'flush_old_exec' into two functions · 221af7f8
      Linus Torvalds 提交于
      'flush_old_exec()' is the point of no return when doing an execve(), and
      it is pretty badly misnamed.  It doesn't just flush the old executable
      environment, it also starts up the new one.
      
      Which is very inconvenient for things like setting up the new
      personality, because we want the new personality to affect the starting
      of the new environment, but at the same time we do _not_ want the new
      personality to take effect if flushing the old one fails.
      
      As a result, the x86-64 '32-bit' personality is actually done using this
      insane "I'm going to change the ABI, but I haven't done it yet" bit
      (TIF_ABI_PENDING), with SET_PERSONALITY() not actually setting the
      personality, but just the "pending" bit, so that "flush_thread()" can do
      the actual personality magic.
      
      This patch in no way changes any of that insanity, but it does split the
      'flush_old_exec()' function up into a preparatory part that can fail
      (still called flush_old_exec()), and a new part that will actually set
      up the new exec environment (setup_new_exec()).  All callers are changed
      to trivially comply with the new world order.
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      Cc: stable@kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      221af7f8
  13. 29 1月, 2010 2 次提交
  14. 28 1月, 2010 1 次提交
    • L
      mm: add new 'read_cache_page_gfp()' helper function · 0531b2aa
      Linus Torvalds 提交于
      It's a simplified 'read_cache_page()' which takes a page allocation
      flag, so that different paths can control how aggressive the memory
      allocations are that populate a address space.
      
      In particular, the intel GPU object mapping code wants to be able to do
      a certain amount of own internal memory management by automatically
      shrinking the address space when memory starts getting tight.  This
      allows it to dynamically use different memory allocation policies on a
      per-allocation basis, rather than depend on the (static) address space
      gfp policy.
      
      The actual new function is a one-liner, but re-organizing the helper
      functions to the point where you can do this with a single line of code
      is what most of the patch is all about.
      Tested-by: NChris Wilson <chris@chris-wilson.co.uk>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0531b2aa
  15. 27 1月, 2010 1 次提交
  16. 25 1月, 2010 1 次提交
  17. 21 1月, 2010 3 次提交
    • P
      perf: Change the is_software_event() definition · 92b67598
      Peter Zijlstra 提交于
      The is_software_event() definition always confuses me because its an
      exclusive expression, make it an inclusive one.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      92b67598
    • M
      sched: Fix vmark regression on big machines · 50b926e4
      Mike Galbraith 提交于
      SD_PREFER_SIBLING is set at the CPU domain level if power saving isn't
      enabled, leading to many cache misses on large machines as we traverse
      looking for an idle shared cache to wake to.  Change the enabler of
      select_idle_sibling() to SD_SHARE_PKG_RESOURCES, and enable same at the
      sibling domain level.
      Reported-by: NLin Ming <ming.m.lin@intel.com>
      Signed-off-by: NMike Galbraith <efault@gmx.de>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      LKML-Reference: <1262612696.15495.15.camel@marge.simson.net>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      50b926e4
    • S
      USB: Fix duplicate sysfs problem after device reset. · 04a723ea
      Sarah Sharp 提交于
      Borislav Petkov reports issues with duplicate sysfs endpoint files after a
      resume from a hibernate.  It turns out that the code to support alternate
      settings under xHCI has issues when a device with a non-default alternate
      setting is reset during the hibernate:
      
      [  427.681810] Restarting tasks ...
      [  427.681995] hub 1-0:1.0: state 7 ports 6 chg 0004 evt 0000
      [  427.682019] usb usb3: usb resume
      [  427.682030] ohci_hcd 0000:00:12.0: wakeup root hub
      [  427.682191] hub 1-0:1.0: port 2, status 0501, change 0000, 480 Mb/s
      [  427.682205] usb 1-2: usb wakeup-resume
      [  427.682226] usb 1-2: finish reset-resume
      [  427.682886] done.
      [  427.734658] ehci_hcd 0000:00:12.2: port 2 high speed
      [  427.734663] ehci_hcd 0000:00:12.2: GetStatus port 2 status 001005 POWER sig=se0 PE CONNECT
      [  427.746682] hub 3-0:1.0: hub_reset_resume
      [  427.746693] hub 3-0:1.0: trying to enable port power on non-switchable hub
      [  427.786715] usb 1-2: reset high speed USB device using ehci_hcd and address 2
      [  427.839653] ehci_hcd 0000:00:12.2: port 2 high speed
      [  427.839666] ehci_hcd 0000:00:12.2: GetStatus port 2 status 001005 POWER sig=se0 PE CONNECT
      [  427.847717] ohci_hcd 0000:00:12.0: GetStatus roothub.portstatus [1] = 0x00010100 CSC PPS
      [  427.915497] hub 1-2:1.0: remove_intf_ep_devs: if: ffff88022f9e8800 ->ep_devs_created: 1
      [  427.915774] hub 1-2:1.0: remove_intf_ep_devs: bNumEndpoints: 1
      [  427.915934] hub 1-2:1.0: if: ffff88022f9e8800: endpoint devs removed.
      [  427.916158] hub 1-2:1.0: create_intf_ep_devs: if: ffff88022f9e8800 ->ep_devs_created: 0, ->unregistering: 0
      [  427.916434] hub 1-2:1.0: create_intf_ep_devs: bNumEndpoints: 1
      [  427.916609]  ep_81: create, parent hub
      [  427.916632] ------------[ cut here ]------------
      [  427.916644] WARNING: at fs/sysfs/dir.c:477 sysfs_add_one+0x82/0x96()
      [  427.916649] Hardware name: System Product Name
      [  427.916653] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:12.2/usb1/1-2/1-2:1.0/ep_81'
      [  427.916658] Modules linked in: binfmt_misc kvm_amd kvm powernow_k8 cpufreq_ondemand cpufreq_powersave cpufreq_userspace freq_table cpufreq_conservative ipv6 vfat fat
      +8250_pnp 8250 pcspkr ohci_hcd serial_core k10temp edac_core
      [  427.916694] Pid: 278, comm: khubd Not tainted 2.6.33-rc2-00187-g08d869aa-dirty #13
      [  427.916699] Call Trace:
      
      The problem is caused by a mismatch between the USB core's view of the
      device state and the USB device and xHCI host's view of the device state.
      
      After the device reset and re-configuration, the device and the xHCI host
      think they are using alternate setting 0 of all interfaces.  However, the
      USB core keeps track of the old state, which may include non-zero
      alternate settings.  It uses intf->cur_altsetting to keep the endpoint
      sysfs files for the old state across the reset.
      
      The bandwidth allocation functions need to know what the xHCI host thinks
      the current alternate settings are, so original patch set
      intf->cur_altsetting to the alternate setting 0.  This caused duplicate
      endpoint files to be created.
      
      The solution is to not set intf->cur_altsetting before calling
      usb_set_interface() in usb_reset_and_verify_device().  Instead, we add a
      new flag to struct usb_interface to tell usb_hcd_alloc_bandwidth() to use
      alternate setting 0 as the currently installed alternate setting.
      Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
      Tested-by: NBorislav Petkov <petkovbb@googlemail.com>
      Cc: Alan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      04a723ea
  18. 19 1月, 2010 2 次提交
  19. 18 1月, 2010 2 次提交
  20. 17 1月, 2010 10 次提交