1. 10 Aug, 2016 14 commits
    • Vegard Nossum's avatar
      sched/debug: Add taint on "BUG: Sleeping function called from invalid context" · f0b22e39
      Vegard Nossum authored
      Seeing this, it occurs to me that we should probably add a taint here:
      
          BUG: sleeping function called from invalid context at mm/slab.h:388
          in_atomic(): 0, irqs_disabled(): 0, pid: 32211, name: trinity-c3
          Preemption disabled at:[<ffffffff811aaa37>] console_unlock+0x2f7/0x930
      
          CPU: 3 PID: 32211 Comm: trinity-c3 Not tainted 4.7.0-rc7+ #19
                                             ^^^^^^^^^^^
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
           0000000000000000 ffff8800b8a17160 ffffffff81971441 ffff88011a3c4c80
           ffff88011a3c4c80 ffff8800b8a17198 ffffffff81158067 0000000000000de6
           ffff88011a3c4c80 ffffffff8390e07c 0000000000000184 0000000000000000
          Call Trace:
          [...]
      
          BUG: sleeping function called from invalid context at arch/x86/mm/fault.c:1309
          in_atomic(): 0, irqs_disabled(): 0, pid: 32211, name: trinity-c3
          Preemption disabled at:[<ffffffff8119db33>] down_trylock+0x13/0x80
      
          CPU: 3 PID: 32211 Comm: trinity-c3 Not tainted 4.7.0-rc7+ #19
                                             ^^^^^^^^^^^
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
           0000000000000000 ffff8800b8a17e08 ffffffff81971441 ffff88011a3c4c80
           ffff88011a3c4c80 ffff8800b8a17e40 ffffffff81158067 0000000000000000
           ffff88011a3c4c80 ffffffff83437b20 000000000000051d 0000000000000000
          Call Trace:
          [...]
      Signed-off-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Acked-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rusty Russel <rusty@rustcorp.com.au>
      Link: http://lkml.kernel.org/r/1469216762-19626-1-git-send-email-vegard.nossum@oracle.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      f0b22e39
    • Vegard Nossum's avatar
      sched/debug: Make the "Preemption disabled at ..." message more useful · d1c6d149
      Vegard Nossum authored
      This message is currently really useless since it always prints a value
      that comes from the printk() we just did, e.g.:
      
          BUG: sleeping function called from invalid context at mm/slab.h:388
          in_atomic(): 0, irqs_disabled(): 0, pid: 31996, name: trinity-c1
          Preemption disabled at:[<ffffffff8119db33>] down_trylock+0x13/0x80
      
          BUG: sleeping function called from invalid context at include/linux/freezer.h:56
          in_atomic(): 0, irqs_disabled(): 0, pid: 31996, name: trinity-c1
          Preemption disabled at:[<ffffffff811aaa37>] console_unlock+0x2f7/0x930
      
      Here, both down_trylock() and console_unlock() is somewhere in the
      printk() path.
      
      We should save the value before calling printk() and use the saved value
      instead. That immediately reveals the offending callsite:
      
          BUG: sleeping function called from invalid context at mm/slab.h:388
          in_atomic(): 0, irqs_disabled(): 0, pid: 14971, name: trinity-c2
          Preemption disabled at:[<ffffffff819bcd46>] rhashtable_walk_start+0x46/0x150
      
      Bug report:
      
        http://marc.info/?l=linux-netdev&m=146925979821849&w=2Signed-off-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rusty Russel <rusty@rustcorp.com.au>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      d1c6d149
    • Juri Lelli's avatar
      sched/deadline: Remove useless parameter from setup_new_dl_entity() · 98b0a857
      Juri Lelli authored
      setup_new_dl_entity() takes two parameters, but it only actually uses
      one of them, under a different name, to setup a new dl_entity, after:
      
        2f9f3fdc928 "sched/deadline: Remove dl_new from struct sched_dl_entity"
      
      as we currently do:
      
        setup_new_dl_entity(&p->dl, &p->dl)
      
      However, before Luca's change we were doing:
      
        setup_new_dl_entity(dl_se, pi_se)
      
      in update_dl_entity() for a dl_se->new entity: we were using pi_se's
      parameters (the potential PI donor) for setting up a new entity.
      
      This change removes the useless second parameter of setup_new_dl_entity().
      
      While we are at it we also optimize things further calling setup_new_dl_
      entity() only for already queued tasks, since (as pointed out by Xunlei)
      we already do the very same update at tasks wakeup time anyway. By doing
      so, we don't need to worry about a potential PI donor anymore, as
      rt_mutex_setprio() takes care of that already for us.
      Signed-off-by: default avatarJuri Lelli <juri.lelli@arm.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Reviewed-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Luca Abeni <luca.abeni@unitn.it>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Xunlei Pang <xpang@redhat.com>
      Link: http://lkml.kernel.org/r/1470409675-20935-1-git-send-email-juri.lelli@arm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      98b0a857
    • Luis de Bethencourt's avatar
      sched/core: Add documentation for 'cookie' argument · 9279e0d2
      Luis de Bethencourt authored
      Add documentation for the cookie argument in try_to_wake_up_local().
      
      This caused the following warning when building documentation:
      
        kernel/sched/core.c:2088: warning: No description found for parameter 'cookie'
      Signed-off-by: default avatarLuis de Bethencourt <luisbg@osg.samsung.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: akpm@linux-foundation.org
      Fixes: e7904a28 ("ilocking/lockdep, sched/core: Implement a better lock pinning scheme")
      Link: http://lkml.kernel.org/r/1468159226-17674-1-git-send-email-luisbg@osg.samsung.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      9279e0d2
    • Morten Rasmussen's avatar
      sched/fair: Optimize find_idlest_cpu() when there is no choice · eaecf41f
      Morten Rasmussen authored
      In the current find_idlest_group()/find_idlest_cpu() search we end up
      calling find_idlest_cpu() in a sched_group containing only one CPU in
      the end. Checking idle-states becomes pointless when there is no
      alternative, so bail out instead.
      Signed-off-by: default avatarMorten Rasmussen <morten.rasmussen@arm.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: dietmar.eggemann@arm.com
      Cc: linux-kernel@vger.kernel.org
      Cc: mgalbraith@suse.de
      Cc: vincent.guittot@linaro.org
      Cc: yuyang.du@intel.com
      Link: http://lkml.kernel.org/r/1466615004-3503-4-git-send-email-morten.rasmussen@arm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      eaecf41f
    • Morten Rasmussen's avatar
      sched/fair: Make the use of prev_cpu consistent in the wakeup path · 772bd008
      Morten Rasmussen authored
      In commit:
      
        ac66f547 ("sched/numa: Introduce migrate_swap()")
      
      select_task_rq() got a 'cpu' argument to enable overriding of prev_cpu
      in special cases (NUMA task swapping).
      
      However, the select_task_rq_fair() helper functions: wake_affine() and
      select_idle_sibling(), still use task_cpu(p) directly to work out
      prev_cpu, which leads to inconsistencies.
      
      This patch passes prev_cpu (potentially overridden by NUMA code) into
      the helper functions to ensure prev_cpu is indeed the same CPU
      everywhere in the wakeup path.
      
      cc: Ingo Molnar <mingo@redhat.com>
      cc: Rik van Riel <riel@redhat.com>
      Signed-off-by: default avatarMorten Rasmussen <morten.rasmussen@arm.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: dietmar.eggemann@arm.com
      Cc: linux-kernel@vger.kernel.org
      Cc: mgalbraith@suse.de
      Cc: vincent.guittot@linaro.org
      Cc: yuyang.du@intel.com
      Link: http://lkml.kernel.org/r/1466615004-3503-3-git-send-email-morten.rasmussen@arm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      772bd008
    • Morten Rasmussen's avatar
      sched/core: Fix power to capacity renaming in comment · bd425d4b
      Morten Rasmussen authored
      It is seems that this one escaped Nico's renaming of cpu_power to
      cpu_capacity a while back.
      Signed-off-by: default avatarMorten Rasmussen <morten.rasmussen@arm.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: dietmar.eggemann@arm.com
      Cc: linux-kernel@vger.kernel.org
      Cc: mgalbraith@suse.de
      Cc: vincent.guittot@linaro.org
      Cc: yuyang.du@intel.com
      Link: http://lkml.kernel.org/r/1466615004-3503-2-git-send-email-morten.rasmussen@arm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      bd425d4b
    • Peter Zijlstra's avatar
      sched/fair: Improve PELT stuff some more · 7c3edd2c
      Peter Zijlstra authored
      Vincent noted that the update_tg_load_avg() usage in commit:
      
        3d30544f ("sched/fair: Apply more PELT fixes")
      
      isn't entirely sufficient. We need to call this function every time
      cfs_rq->avg.load changes, this includes when update_cfs_rq_load_avg()
      returns true, but {attach,detach}_entity_load_avg() themselves also
      change it. This means we need to unconditionally call
      update_tg_load_avg().
      
      Also, add more comments.
      Reported-by: default avatarVincent Guittot <vincent.guittot@linaro.org>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      7c3edd2c
    • Leo Yan's avatar
      sched/core: Fix one typo · a1fd4656
      Leo Yan authored
      Fix one minor typo in the comment: s/targer/target/.
      Signed-off-by: default avatarLeo Yan <leo.yan@linaro.org>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Link: http://lkml.kernel.org/r/1470378758-15066-1-git-send-email-leo.yan@linaro.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      a1fd4656
    • Leo Yan's avatar
      sched/fair: Remove 'cpu_busy' parameter from update_next_balance() · 31851a98
      Leo Yan authored
      The update_next_balance() function is only used by idle balancing, so its
      'cpu_busy' parameter is always 0.
      
      Open code it instead of passing it around.
      Signed-off-by: default avatarLeo Yan <leo.yan@linaro.org>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Link: http://lkml.kernel.org/r/1470378689-14892-1-git-send-email-leo.yan@linaro.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      31851a98
    • Wanpeng Li's avatar
      sched/deadline: Fix lock pinning warning during CPU hotplug · c0c8c9fa
      Wanpeng Li authored
      The following warning can be triggered by hot-unplugging the CPU
      on which an active SCHED_DEADLINE task is running on:
      
        WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:3531 lock_release+0x690/0x6a0
        releasing a pinned lock
        Call Trace:
         dump_stack+0x99/0xd0
         __warn+0xd1/0xf0
         ? dl_task_timer+0x1a1/0x2b0
         warn_slowpath_fmt+0x4f/0x60
         ? sched_clock+0x13/0x20
         lock_release+0x690/0x6a0
         ? enqueue_pushable_dl_task+0x9b/0xa0
         ? enqueue_task_dl+0x1ca/0x480
         _raw_spin_unlock+0x1f/0x40
         dl_task_timer+0x1a1/0x2b0
         ? push_dl_task.part.31+0x190/0x190
        WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:3649 lock_unpin_lock+0x181/0x1a0
        unpinning an unpinned lock
        Call Trace:
         dump_stack+0x99/0xd0
         __warn+0xd1/0xf0
         warn_slowpath_fmt+0x4f/0x60
         lock_unpin_lock+0x181/0x1a0
         dl_task_timer+0x127/0x2b0
         ? push_dl_task.part.31+0x190/0x190
      
      As per the comment before this code, its safe to drop the RQ lock
      here, and since we (potentially) change rq, unpin and repin to avoid
      the splat.
      Signed-off-by: default avatarWanpeng Li <wanpeng.li@hotmail.com>
      [ Rewrote changelog. ]
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Juri Lelli <juri.lelli@arm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Luca Abeni <luca.abeni@unitn.it>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/1470274940-17976-1-git-send-email-wanpeng.li@hotmail.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      c0c8c9fa
    • Giovanni Gherdovich's avatar
      sched/cputime: Mitigate performance regression in times()/clock_gettime() · 6075620b
      Giovanni Gherdovich authored
      Commit:
      
        6e998916 ("sched/cputime: Fix clock_nanosleep()/clock_gettime() inconsistency")
      
      fixed a problem whereby clock_nanosleep() followed by clock_gettime() could
      allow a task to wake early. It addressed the problem by calling the scheduling
      classes update_curr() when the cputimer starts.
      
      Said change induced a considerable performance regression on the syscalls
      times() and clock_gettimes(CLOCK_PROCESS_CPUTIME_ID). There are some
      debuggers and applications that monitor their own performance that
      accidentally depend on the performance of these specific calls.
      
      This patch mitigates the performace loss by prefetching data in the CPU
      cache, as stalls due to cache misses appear to be where most time is spent
      in our benchmarks.
      
      Here are the performance gain of this patch over v4.7-rc7 on a Sandy Bridge
      box with 32 logical cores and 2 NUMA nodes. The test is repeated with a
      variable number of threads, from 2 to 4*num_cpus; the results are in
      seconds and correspond to the average of 10 runs; the percentage gain is
      computed with (before-after)/before so a positive value is an improvement
      (it's faster). The improvement varies between a few percents for 5-20
      threads and more than 10% for 2 or >20 threads.
      
      pound_clock_gettime:
      
          threads       4.7-rc7     patched 4.7-rc7
          [num]         [secs]      [secs (percent)]
            2           3.48        3.06 ( 11.83%)
            5           3.33        3.25 (  2.40%)
            8           3.37        3.26 (  3.30%)
           12           3.32        3.37 ( -1.60%)
           21           4.01        3.90 (  2.74%)
           30           3.63        3.36 (  7.41%)
           48           3.71        3.11 ( 16.27%)
           79           3.75        3.16 ( 15.74%)
          110           3.81        3.25 ( 14.80%)
          128           3.88        3.31 ( 14.76%)
      
      pound_times:
      
          threads       4.7-rc7     patched 4.7-rc7
          [num]         [secs]      [secs (percent)]
            2           3.65        3.25 ( 11.03%)
            5           3.45        3.17 (  7.92%)
            8           3.52        3.22 (  8.69%)
           12           3.29        3.36 ( -2.04%)
           21           4.07        3.92 (  3.78%)
           30           3.87        3.40 ( 12.17%)
           48           3.79        3.16 ( 16.61%)
           79           3.88        3.28 ( 15.42%)
          110           3.90        3.38 ( 13.35%)
          128           4.00        3.38 ( 15.45%)
      
      pound_clock_gettime and pound_clock_gettime are two benchmarks included in
      the MMTests framework. They launch a given number of threads which
      repeatedly call times() or clock_gettimes(). The results above can be
      reproduced with cloning MMTests from github.com and running the "poundtime"
      workload:
      
        $ git clone https://github.com/gormanm/mmtests.git
        $ cd mmtests
        $ cp configs/config-global-dhp__workload_poundtime config
        $ ./run-mmtests.sh --run-monitor $(uname -r)
      
      The above will run "poundtime" measuring the kernel currently running on
      the machine; Once a new kernel is installed and the machine rebooted,
      running again
      
        $ cd mmtests
        $ ./run-mmtests.sh --run-monitor $(uname -r)
      
      will produce results to compare with. A comparison table will be output
      with:
      
        $ cd mmtests/work/log
        $ ../../compare-kernels.sh
      
      the table will contain a lot of entries; grepping for "Amean" (as in
      "arithmetic mean") will give the tables presented above. The source code
      for the two benchmarks is reported at the end of this changelog for
      clairity.
      
      The cache misses addressed by this patch were found using a combination of
      `perf top`, `perf record` and `perf annotate`. The incriminated lines were
      found to be
      
          struct sched_entity *curr = cfs_rq->curr;
      
      and
      
          delta_exec = now - curr->exec_start;
      
      in the function update_curr() from kernel/sched/fair.c. This patch
      prefetches the data from memory just before update_curr is called in the
      interested execution path.
      
      A comparison of the total number of cycles before and after the patch
      follows; the data is obtained using `perf stat -r 10 -ddd <program>`
      running over the same sequence of number of threads used above (a positive
      gain is an improvement):
      
        threads   cycles before                 cycles after                gain
      
          2      19,699,563,964  +-1.19%      17,358,917,517  +-1.85%      11.88%
          5      47,401,089,566  +-2.96%      45,103,730,829  +-0.97%       4.85%
          8      80,923,501,004  +-3.01%      71,419,385,977  +-0.77%      11.74%
         12     112,326,485,473  +-0.47%     110,371,524,403  +-0.47%       1.74%
         21     193,455,574,299  +-0.72%     180,120,667,904  +-0.36%       6.89%
         30     315,073,519,013  +-1.64%     271,222,225,950  +-1.29%      13.92%
         48     321,969,515,332  +-1.48%     273,353,977,321  +-1.16%      15.10%
         79     337,866,003,422  +-0.97%     289,462,481,538  +-1.05%      14.33%
        110     338,712,691,920  +-0.78%     290,574,233,170  +-0.77%      14.21%
        128     348,384,794,006  +-0.50%     292,691,648,206  +-0.66%      15.99%
      
      A comparison of cache miss vs total cache loads ratios, before and after
      the patch (again from the `perf stat -r 10 -ddd <program>` tables):
      
        threads   L1 misses/total*100     L1 misses/total*100            gain
      		         before                   after
            2           7.43  +-4.90%           7.36  +-4.70%           0.94%
            5          13.09  +-4.74%          13.52  +-3.73%          -3.28%
            8          13.79  +-5.61%          12.90  +-3.27%           6.45%
           12          11.57  +-2.44%           8.71  +-1.40%          24.72%
           21          12.39  +-3.92%           9.97  +-1.84%          19.53%
           30          13.91  +-2.53%          11.73  +-2.28%          15.67%
           48          13.71  +-1.59%          12.32  +-1.97%          10.14%
           79          14.44  +-0.66%          13.40  +-1.06%           7.20%
          110          15.86  +-0.50%          14.46  +-0.59%           8.83%
          128          16.51  +-0.32%          15.06  +-0.78%           8.78%
      
      As a final note, the following shows the evolution of performance figures
      in the "poundtime" benchmark and pinpoints commit 6e998916
      ("sched/cputime: Fix clock_nanosleep()/clock_gettime() inconsistency") as a
      major source of degradation, mostly unaddressed to this day (figures
      expressed in seconds).
      
      pound_clock_gettime:
      
        threads   parent of         6e998916        4.7-rc7
      	    6e998916            itself
          2        2.23          3.68 ( -64.56%)        3.48 (-55.48%)
          5        2.83          3.78 ( -33.42%)        3.33 (-17.43%)
          8        2.84          4.31 ( -52.12%)        3.37 (-18.76%)
          12       3.09          3.61 ( -16.74%)        3.32 ( -7.17%)
          21       3.14          4.63 ( -47.36%)        4.01 (-27.71%)
          30       3.28          5.75 ( -75.37%)        3.63 (-10.80%)
          48       3.02          6.05 (-100.56%)        3.71 (-22.99%)
          79       2.88          6.30 (-118.90%)        3.75 (-30.26%)
          110      2.95          6.46 (-119.00%)        3.81 (-29.24%)
          128      3.05          6.42 (-110.08%)        3.88 (-27.04%)
      
      pound_times:
      
        threads   parent of         6e998916        4.7-rc7
      	    6e998916            itself
          2        2.27          3.73 ( -64.71%)        3.65 (-61.14%)
          5        2.78          3.77 ( -35.56%)        3.45 (-23.98%)
          8        2.79          4.41 ( -57.71%)        3.52 (-26.05%)
          12       3.02          3.56 ( -17.94%)        3.29 ( -9.08%)
          21       3.10          4.61 ( -48.74%)        4.07 (-31.34%)
          30       3.33          5.75 ( -72.53%)        3.87 (-16.01%)
          48       2.96          6.06 (-105.04%)        3.79 (-28.10%)
          79       2.88          6.24 (-116.83%)        3.88 (-34.81%)
          110      2.98          6.37 (-114.08%)        3.90 (-31.12%)
          128      3.10          6.35 (-104.61%)        4.00 (-28.87%)
      
      The source code of the two benchmarks follows. To compile the two:
      
        NR_THREADS=42
        for FILE in pound_times pound_clock_gettime; do
            gcc -lrt -O2 -lpthread -DNUM_THREADS=$NR_THREADS $FILE.c -o $FILE
        done
      
      ==== BEGIN pound_times.c ====
      
      struct tms start;
      
      void *pound (void *threadid)
      {
        struct tms end;
        int oldutime = 0;
        int utime;
        int i;
        for (i = 0; i < 5000000 / NUM_THREADS; i++) {
                times(&end);
                utime = ((int)end.tms_utime - (int)start.tms_utime);
                if (oldutime > utime) {
                  printf("utime decreased, was %d, now %d!\n", oldutime, utime);
                }
                oldutime = utime;
        }
        pthread_exit(NULL);
      }
      
      int main()
      {
        pthread_t th[NUM_THREADS];
        long i;
        times(&start);
        for (i = 0; i < NUM_THREADS; i++) {
          pthread_create (&th[i], NULL, pound, (void *)i);
        }
        pthread_exit(NULL);
        return 0;
      }
      ==== END pound_times.c ====
      
      ==== BEGIN pound_clock_gettime.c ====
      
      void *pound (void *threadid)
      {
      	struct timespec ts;
      	int rc, i;
      	unsigned long prev = 0, this = 0;
      
      	for (i = 0; i < 5000000 / NUM_THREADS; i++) {
      		rc = clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts);
      		if (rc < 0)
      			perror("clock_gettime");
      		this = (ts.tv_sec * 1000000000) + ts.tv_nsec;
      		if (0 && this < prev)
      			printf("%lu ns timewarp at iteration %d\n", prev - this, i);
      		prev = this;
      	}
      	pthread_exit(NULL);
      }
      
      int main()
      {
      	pthread_t th[NUM_THREADS];
      	long rc, i;
      	pid_t pgid;
      
      	for (i = 0; i < NUM_THREADS; i++) {
      		rc = pthread_create(&th[i], NULL, pound, (void *)i);
      		if (rc < 0)
      			perror("pthread_create");
      	}
      
      	pthread_exit(NULL);
      	return 0;
      }
      ==== END pound_clock_gettime.c ====
      Suggested-by: default avatarMike Galbraith <mgalbraith@suse.de>
      Signed-off-by: default avatarGiovanni Gherdovich <ggherdovich@suse.cz>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stanislaw Gruszka <sgruszka@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/1470385316-15027-2-git-send-email-ggherdovich@suse.czSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      6075620b
    • Xunlei Pang's avatar
      sched/fair: Fix typo in sync_throttle() · b8922125
      Xunlei Pang authored
      We should update cfs_rq->throttled_clock_task, not
      pcfs_rq->throttle_clock_task.
      
      The effects of this bug was probably occasionally erratic
      group scheduling, particularly in cgroups-intense workloads.
      Signed-off-by: default avatarXunlei Pang <xlpang@redhat.com>
      [ Added changelog. ]
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Acked-by: default avatarKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Fixes: 55e16d30 ("sched/fair: Rework throttle_count sync")
      Link: http://lkml.kernel.org/r/1468050862-18864-1-git-send-email-xlpang@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      b8922125
    • Tommaso Cucinotta's avatar
      sched/deadline: Fix wrap-around in DL heap · a23eadfa
      Tommaso Cucinotta authored
      Current code in cpudeadline.c has a bug in re-heapifying when adding a
      new element at the end of the heap, because a deadline value of 0 is
      temporarily set in the new elem, then cpudl_change_key() is called
      with the actual elem deadline as param.
      
      However, the function compares the new deadline to set with the one
      previously in the elem, which is 0.  So, if current absolute deadlines
      grew so much to have negative values as s64, the comparison in
      cpudl_change_key() makes the wrong decision.  Instead, as from
      dl_time_before(), the kernel should handle correctly abs deadlines
      wrap-arounds.
      
      This patch fixes the problem with a minimally invasive change that
      forces cpudl_change_key() to heapify up in this case.
      Signed-off-by: default avatarTommaso Cucinotta <tommaso.cucinotta@sssup.it>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Reviewed-by: default avatarLuca Abeni <luca.abeni@unitn.it>
      Cc: Juri Lelli <juri.lelli@arm.com>
      Cc: Juri Lelli <juri.lelli@gmail.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/1468921493-10054-2-git-send-email-tommaso.cucinotta@sssup.itSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      a23eadfa
  2. 09 Aug, 2016 14 commits
    • Linus Torvalds's avatar
      Revert "printk: create pr_<level> functions" · a0cba217
      Linus Torvalds authored
      This reverts commit 874f9c7d.
      
      Geert Uytterhoeven reports:
       "This change seems to have an (unintendent?) side-effect.
      
        Before, pr_*() calls without a trailing newline characters would be
        printed with a newline character appended, both on the console and in
        the output of the dmesg command.
      
        After this commit, no new line character is appended, and the output
        of the next pr_*() call of the same type may be appended, like in:
      
          - Truncating RAM at 0x0000000040000000-0x00000000c0000000 to -0x0000000070000000
          - Ignoring RAM at 0x0000000200000000-0x0000000240000000 (!CONFIG_HIGHMEM)
          + Truncating RAM at 0x0000000040000000-0x00000000c0000000 to -0x0000000070000000Ignoring RAM at 0x0000000200000000-0x0000000240000000 (!CONFIG_HIGHMEM)"
      
      Joe Perches says:
       "No, that is not intentional.
      
        The newline handling code inside vprintk_emit is a bit involved and
        for now I suggest a revert until this has all the same behavior as
        earlier"
      Reported-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Requested-by: default avatarJoe Perches <joe@perches.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a0cba217
    • Linus Torvalds's avatar
      Merge tag 'trace-v4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace · 84bd8d33
      Linus Torvalds authored
      Pull tracing fix from Steven Rostedt:
       "Fix tick_stop tracepoint symbols for user export.
      
        Luiz Capitulino noticed that the tick_stop tracepoint wasn't being
        parsed properly by the tracing user space tools.
      
        This was due to the TRACE_DEFINE_ENUM() being set to a define, when it
        should have been set to the enum itself.  The define was of the MASK
        that used the BIT to shift.  The BIT was the enum and by adding that,
        everything gets converted nicely.  The MASK is still kept just in case
        it gets converted to an enum in the future"
      
      * tag 'trace-v4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
        tracing: Fix tick_stop tracepoint symbols for user export
      84bd8d33
    • Linus Torvalds's avatar
      Merge tag 'gcc-plugin-infrastructure-v4.8-rc2' of... · b79f34d6
      Linus Torvalds authored
      Merge tag 'gcc-plugin-infrastructure-v4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
      
      Pull gcc plugin improvements from Kees Cook:
       "Several fixes/improvements for the gcc plugin infrastructure:
      
         - fix a problem with gcc plugins interfering with cc-option tests.
      
         - abort more gracefully when gcc plugin headers or compiler support
           is missing.
      
         - improve the gcc plugin rule generation to be more dynamic, pass
           arguments, and build from subdirectories"
      
      * tag 'gcc-plugin-infrastructure-v4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
        gcc-plugins: Add support for plugin subdirectories
        gcc-plugins: Automate make rule generation
        gcc-plugins: Add support for passing plugin arguments
        gcc-plugins: abort builds cleanly when not supported
        kbuild: no gcc-plugins during cc-option tests
      b79f34d6
    • Linus Torvalds's avatar
      Merge tag 'platform-drivers-x86-v4.8-3' of... · e1d009ea
      Linus Torvalds authored
      Merge tag 'platform-drivers-x86-v4.8-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86
      
      Pull x86 platform driver update from Darren Hart:
       "dell-wmi: ignore battery remove/insert event"
      
      * tag 'platform-drivers-x86-v4.8-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
        dell-wmi: Ignore WMI event 0xe00e
      e1d009ea
    • Linus Torvalds's avatar
      Merge tag 'drm-fixes-for-4.8-rc2' of git://people.freedesktop.org/~airlied/linux · cb0d93aa
      Linus Torvalds authored
      Pull drm fixes from Dave Airlie:
       "This contains a bunch of amdgpu fixes, and some i915 regression fixes.
      
        It also contains some fixes for an older regression with some EDID
        changes and some 6bpc panels.
      
        Then there are the lockdep, cirrus and rcar-du regression fixes from
        this window"
      
      * tag 'drm-fixes-for-4.8-rc2' of git://people.freedesktop.org/~airlied/linux:
        drm/cirrus: Fix NULL pointer dereference when registering the fbdev
        drm/edid: Set 8 bpc color depth for displays with "DFP 1.x compliant TMDS".
        drm/i915/dp: Revert "drm/i915/dp: fall back to 18 bpp when sink capability is unknown"
        drm/edid: Add 6 bpc quirk for display AEO model 0.
        drm: Paper over locking inversion after registration rework
        drm: rcar-du: Link HDMI encoder with bridge
        drm/ttm: Wait for a BO to become idle before unbinding it from GTT
        drm/i915/fbdev: Check for the framebuffer before use
        drm/amdgpu: update golden setting of polaris10
        drm/amdgpu: update golden setting of stoney
        drm/amdgpu: update golden setting of polaris11
        drm/amdgpu: update golden setting of carrizo
        drm/amdgpu: update golden setting of iceland
        drm/amd/amdgpu: change pptable output format from ASCII to binary
        drm/amdgpu/ci: add mullins to default case for smc ucode
        drm/amdgpu/gmc7: add missing mullins case
        drm/i915: Never fully mask the the EI up rps interrupt on SNB/IVB
        drm/i915: Wait up to 3ms for the pcu to ack the cdclk change request on SKL
      cb0d93aa
    • Brian King's avatar
      ipr: Fix sync scsi scan · a3d1ddd9
      Brian King authored
      Commit b195d5e2 ("ipr: Wait to do async scan until scsi host is
      initialized") fixed async scan for ipr, but broke sync scan for ipr.
      
      This fixes sync scan back up.
      Signed-off-by: default avatarBrian King <brking@linux.vnet.ibm.com>
      Reported-and-tested-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a3d1ddd9
    • Vladimir Davydov's avatar
      mm: memcontrol: only mark charged pages with PageKmemcg · c4159a75
      Vladimir Davydov authored
      To distinguish non-slab pages charged to kmemcg we mark them PageKmemcg,
      which sets page->_mapcount to -512.  Currently, we set/clear PageKmemcg
      in __alloc_pages_nodemask()/free_pages_prepare() for any page allocated
      with __GFP_ACCOUNT, including those that aren't actually charged to any
      cgroup, i.e. allocated from the root cgroup context.  To avoid overhead
      in case cgroups are not used, we only do that if memcg_kmem_enabled() is
      true.  The latter is set iff there are kmem-enabled memory cgroups
      (online or offline).  The root cgroup is not considered kmem-enabled.
      
      As a result, if a page is allocated with __GFP_ACCOUNT for the root
      cgroup when there are kmem-enabled memory cgroups and is freed after all
      kmem-enabled memory cgroups were removed, e.g.
      
        # no memory cgroups has been created yet, create one
        mkdir /sys/fs/cgroup/memory/test
        # run something allocating pages with __GFP_ACCOUNT, e.g.
        # a program using pipe
        dmesg | tail
        # remove the memory cgroup
        rmdir /sys/fs/cgroup/memory/test
      
      we'll get bad page state bug complaining about page->_mapcount != -1:
      
        BUG: Bad page state in process swapper/0  pfn:1fd945c
        page:ffffea007f651700 count:0 mapcount:-511 mapping:          (null) index:0x0
        flags: 0x1000000000000000()
      
      To avoid that, let's mark with PageKmemcg only those pages that are
      actually charged to and hence pin a non-root memory cgroup.
      
      Fixes: 4949148a ("mm: charge/uncharge kmemcg from generic page allocator paths")
      Reported-and-tested-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: default avatarVladimir Davydov <vdavydov@virtuozzo.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c4159a75
    • Steven Rostedt (Red Hat)'s avatar
      tracing: Fix tick_stop tracepoint symbols for user export · c87edb36
      Steven Rostedt (Red Hat) authored
      The symbols used in the tick_stop tracepoint were not being converted
      properly into integers in the trace_stop format file. Instead we had this:
      
      print fmt: "success=%d dependency=%s", REC->success,
          __print_symbolic(REC->dependency, { 0, "NONE" },
           { (1 << TICK_DEP_BIT_POSIX_TIMER), "POSIX_TIMER" },
           { (1 << TICK_DEP_BIT_PERF_EVENTS), "PERF_EVENTS" },
           { (1 << TICK_DEP_BIT_SCHED), "SCHED" },
           { (1 << TICK_DEP_BIT_CLOCK_UNSTABLE), "CLOCK_UNSTABLE" })
      
      User space tools have no idea how to parse "TICK_DEP_BIT_SCHED" or the other
      symbols used to do the bit shifting. The reason is that the conversion was
      done with using the TICK_DEP_MASK_* symbols which are just macros that
      convert to the BIT shift itself (with the exception of NONE, which was
      converted properly, because it doesn't use bits, and is defined as zero).
      
      The TICK_DEP_BIT_* needs to be denoted by TRACE_DEFINE_ENUM() in order to
      have this properly converted for user space tools to parse this event.
      
      Cc: stable@vger.kernel.org
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Fixes: e6e6cc22 ("nohz: Use enum code for tick stop failure tracing message")
      Reported-by: default avatarLuiz Capitulino <lcapitulino@redhat.com>
      Tested-by: default avatarLuiz Capitulino <lcapitulino@redhat.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      c87edb36
    • Boris Brezillon's avatar
      drm/cirrus: Fix NULL pointer dereference when registering the fbdev · 36e9d08b
      Boris Brezillon authored
      cirrus_modeset_init() is initializing/registering the emulated fbdev
      and, since commit c61b93fe ("drm/atomic: Fix remaining places where
      !funcs->best_encoder is valid"), DRM internals can access/test some of
      the fields in mode_config->funcs as part of the fbdev registration
      process.
      Make sure dev->mode_config.funcs is properly set to avoid dereferencing
      a NULL pointer.
      Reported-by: default avatarMike Marshall <hubcap@omnibond.com>
      Reported-by: default avatarEric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
      Fixes: c61b93fe ("drm/atomic: Fix remaining places where !funcs->best_encoder is valid")
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      36e9d08b
    • Emese Revfy's avatar
      gcc-plugins: Add support for plugin subdirectories · caefd8c9
      Emese Revfy authored
      This adds support for building more complex gcc plugins that live in a
      subdirectory instead of just in a single source file.
      Reported-by: default avatarPaX Team <pageexec@freemail.hu>
      Signed-off-by: default avatarEmese Revfy <re.emese@gmail.com>
      [kees: clarified commit message]
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      caefd8c9
    • Emese Revfy's avatar
      gcc-plugins: Automate make rule generation · 7040c83b
      Emese Revfy authored
      There's no reason to repeat the same names in the Makefile when the .so
      files have already been listed. The .o list can be generated from them.
      Reported-by: default avatarPaX Team <pageexec@freemail.hu>
      Signed-off-by: default avatarEmese Revfy <re.emese@gmail.com>
      [kees: clarified commit message]
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      7040c83b
    • Emese Revfy's avatar
      gcc-plugins: Add support for passing plugin arguments · 65d59ec8
      Emese Revfy authored
      The latent_entropy plugin needs to pass arguments, so this adds the
      support.
      Signed-off-by: default avatarEmese Revfy <re.emese@gmail.com>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      65d59ec8
    • Kees Cook's avatar
      gcc-plugins: abort builds cleanly when not supported · ed58c0e9
      Kees Cook authored
      When the compiler doesn't support gcc plugins (either due to missing
      headers or too old a version), report the problem and abort the build
      instead of emitting a warning and letting the build founder with arcane
      compiler errors.
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      ed58c0e9
    • Emese Revfy's avatar
      kbuild: no gcc-plugins during cc-option tests · d26e9414
      Emese Revfy authored
      The gcc-plugins arguments should not be included when performing
      cc-option tests.
      
      Steps to reproduce:
      1) make mrproper
      2) make defconfig
      3) enable GCC_PLUGINS, GCC_PLUGIN_CYC_COMPLEXITY
      4) enable FUNCTION_TRACER (it will select other options as well)
      5) make && make modules
      
      Build errors:
      MODPOST 18 modules
      ERROR: "__fentry__" [net/netfilter/xt_nat.ko] undefined!
      ERROR: "__fentry__" [net/netfilter/xt_mark.ko] undefined!
      ERROR: "__fentry__" [net/netfilter/xt_addrtype.ko] undefined!
      ERROR: "__fentry__" [net/netfilter/xt_LOG.ko] undefined!
      ERROR: "__fentry__" [net/netfilter/nf_nat_sip.ko] undefined!
      ERROR: "__fentry__" [net/netfilter/nf_nat_irc.ko] undefined!
      ERROR: "__fentry__" [net/netfilter/nf_nat_ftp.ko] undefined!
      ERROR: "__fentry__" [net/netfilter/nf_nat.ko] undefined!
      Reported-by: default avatarLaura Abbott <labbott@redhat.com>
      Signed-off-by: default avatarEmese Revfy <re.emese@gmail.com>
      [kees: renamed variable, clarified commit message]
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      d26e9414
  3. 08 Aug, 2016 12 commits
    • Mario Kleiner's avatar
      drm/edid: Set 8 bpc color depth for displays with "DFP 1.x compliant TMDS". · 210a021d
      Mario Kleiner authored
      According to E-EDID spec 1.3, table 3.9, a digital video sink with the
      "DFP 1.x compliant TMDS" bit set is "signal compatible with VESA DFP 1.x
      TMDS CRGB, 1 pixel / clock, up to 8 bits / color MSB aligned".
      
      For such displays, the DFP spec 1.0, section 3.10 "EDID support" says:
      
      "If the DFP monitor only supports EDID 1.X (1.1, 1.2, etc.)
       without extensions, the host will make the following assumptions:
      
       1. 24-bit MSB-aligned RGB TFT
       2. DE polarity is active high
       3. H and V syncs are active high
       4. Established CRT timings will be used
       5. Dithering will not be enabled on the host"
      
      So if we don't know the bit depth of the display from additional
      colorimetry info we should assume 8 bpc / 24 bpp by default.
      
      This patch adds info->bpc = 8 assignement for that case.
      Signed-off-by: default avatarMario Kleiner <mario.kleiner.de@gmail.com>
      Cc: Jani Nikula <jani.nikula@intel.com>
      Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
      Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      210a021d
    • Mario Kleiner's avatar
      drm/i915/dp: Revert "drm/i915/dp: fall back to 18 bpp when sink capability is unknown" · 196f954e
      Mario Kleiner authored
      This reverts commit 013dd9e0
      ("drm/i915/dp: fall back to 18 bpp when sink capability is unknown")
      
      This commit introduced a regression into stable kernels,
      as it reduces output color depth to 6 bpc for any video
      sink connected to a Displayport connector if that sink
      doesn't report a specific color depth via EDID, or if
      our EDID parser doesn't actually recognize the proper
      bpc from EDID.
      
      Affected are active DisplayPort->VGA converters and
      active DisplayPort->DVI converters. Both should be
      able to handle 8 bpc, but are degraded to 6 bpc with
      this patch.
      
      The reverted commit was meant to fix
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=105331
      
      A followup patch implements a fix for that specific bug,
      which is caused by a faulty EDID of the affected DP panel
      by adding a new EDID quirk for that panel.
      
      DP 18 bpp fallback handling and other improvements to
      DP sink bpc detection will be handled for future
      kernels in a separate series of patches.
      
      Please backport to stable.
      Signed-off-by: default avatarMario Kleiner <mario.kleiner.de@gmail.com>
      Acked-by: default avatarJani Nikula <jani.nikula@intel.com>
      Cc: stable@vger.kernel.org
      Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
      Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      196f954e
    • Mario Kleiner's avatar
      drm/edid: Add 6 bpc quirk for display AEO model 0. · e10aec65
      Mario Kleiner authored
      Bugzilla https://bugzilla.kernel.org/show_bug.cgi?id=105331
      reports that the "AEO model 0" display is driven with 8 bpc
      without dithering by default, which looks bad because that
      panel is apparently a 6 bpc DP panel with faulty EDID.
      
      A fix for this was made by commit 013dd9e0
      ("drm/i915/dp: fall back to 18 bpp when sink capability is unknown").
      
      That commit triggers new regressions in precision for DP->DVI and
      DP->VGA displays. A patch is out to revert that commit, but it will
      revert video output for the AEO model 0 panel to 8 bpc without
      dithering.
      
      The EDID 1.3 of that panel, as decoded from the xrandr output
      attached to that bugzilla bug report, is somewhat faulty, and beyond
      other problems also sets the "DFP 1.x compliant TMDS" bit, which
      according to DFP spec means to drive the panel with 8 bpc and
      no dithering in absence of other colorimetry information.
      
      Try to make the original bug reporter happy despite the
      faulty EDID by adding a quirk to mark that panel as 6 bpc,
      so 6 bpc output with dithering creates a nice picture.
      
      Tested by injecting the edid from the fdo bug into a DP connector
      via drm_kms_helper.edid_firmware and verifying the 6 bpc + dithering
      is selected.
      
      This patch should be backported to stable.
      Signed-off-by: default avatarMario Kleiner <mario.kleiner.de@gmail.com>
      Cc: stable@vger.kernel.org
      Cc: Jani Nikula <jani.nikula@intel.com>
      Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
      Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      e10aec65
    • Linus Torvalds's avatar
      Merge tag 'lkdtm-v4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux · 81abf252
      Linus Torvalds authored
      Pull lkdtm update from Kees Cook:
       "Fix rebuild problem with LKDTM's rodata test"
      
      [ This, and the usercopy branch, both came in before the merge window
        closed, but ended up in my 'need to look more' queue and thus got
        merged only after rc1 was out ]
      
      * tag 'lkdtm-v4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
        lkdtm: Fix targets for objcopy usage
        lkdtm: fix false positive warning from -Wmaybe-uninitialized
      81abf252
    • Linus Torvalds's avatar
      Merge tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux · 1eccfa09
      Linus Torvalds authored
      Pull usercopy protection from Kees Cook:
       "Tbhis implements HARDENED_USERCOPY verification of copy_to_user and
        copy_from_user bounds checking for most architectures on SLAB and
        SLUB"
      
      * tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
        mm: SLUB hardened usercopy support
        mm: SLAB hardened usercopy support
        s390/uaccess: Enable hardened usercopy
        sparc/uaccess: Enable hardened usercopy
        powerpc/uaccess: Enable hardened usercopy
        ia64/uaccess: Enable hardened usercopy
        arm64/uaccess: Enable hardened usercopy
        ARM: uaccess: Enable hardened usercopy
        x86/uaccess: Enable hardened usercopy
        mm: Hardened usercopy
        mm: Implement stack frame object validation
        mm: Add is_migrate_cma_page
      1eccfa09
    • Linus Torvalds's avatar
      unsafe_[get|put]_user: change interface to use a error target label · 1bd4403d
      Linus Torvalds authored
      When I initially added the unsafe_[get|put]_user() helpers in commit
      5b24a7a2 ("Add 'unsafe' user access functions for batched
      accesses"), I made the mistake of modeling the interface on our
      traditional __[get|put]_user() functions, which return zero on success,
      or -EFAULT on failure.
      
      That interface is fairly easy to use, but it's actually fairly nasty for
      good code generation, since it essentially forces the caller to check
      the error value for each access.
      
      In particular, since the error handling is already internally
      implemented with an exception handler, and we already use "asm goto" for
      various other things, we could fairly easily make the error cases just
      jump directly to an error label instead, and avoid the need for explicit
      checking after each operation.
      
      So switch the interface to pass in an error label, rather than checking
      the error value in the caller.  Best do it now before we start growing
      more users (the signal handling code in particular would be a good place
      to use the new interface).
      
      So rather than
      
      	if (unsafe_get_user(x, ptr))
      		... handle error ..
      
      the interface is now
      
      	unsafe_get_user(x, ptr, label);
      
      where an error during the user mode fetch will now just cause a jump to
      'label' in the caller.
      
      Right now the actual _implementation_ of this all still ends up being a
      "if (err) goto label", and does not take advantage of any exception
      label tricks, but for "unsafe_put_user()" in particular it should be
      fairly straightforward to convert to using the exception table model.
      
      Note that "unsafe_get_user()" is much harder to convert to a clever
      exception table model, because current versions of gcc do not allow the
      use of "asm goto" (for the exception) with output values (for the actual
      value to be fetched).  But that is hopefully not a limitation in the
      long term.
      
      [ Also note that it might be a good idea to switch unsafe_get_user() to
        actually _return_ the value it fetches from user space, but this
        commit only changes the error handling semantics ]
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1bd4403d
    • Andreas Ziegler's avatar
      printk: Remove unnecessary #ifdef CONFIG_PRINTK · 574673c2
      Andreas Ziegler authored
      In commit 874f9c7d ("printk: create pr_<level> functions"), new
      pr_level defines were added to printk.c.
      
      These new defines are guarded by an #ifdef CONFIG_PRINTK - however,
      there is already a surrounding #ifdef CONFIG_PRINTK starting a lot
      earlier in line 249 which means the newly introduced #ifdef is
      unnecessary.
      
      Let's remove it to avoid confusion.
      Signed-off-by: default avatarAndreas Ziegler <andreas.ziegler@fau.de>
      Cc: Joe Perches <joe@perches.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      574673c2
    • Pali Rohár's avatar
      dell-wmi: Ignore WMI event 0xe00e · 65a97a67
      Pali Rohár authored
      WMI event 0xe00e is received when battery was removed or inserted.
      Signed-off-by: default avatarPali Rohár <pali.rohar@gmail.com>
      Signed-off-by: default avatarDarren Hart <dvhart@linux.intel.com>
      65a97a67
    • Ville Syrjälä's avatar
      x86/hweight: Don't clobber %rdi · 65ea11ec
      Ville Syrjälä authored
      The caller expects %rdi to remain intact, push+pop it make that happen.
      
      Fixes the following kind of explosions on my core2duo machine when
      trying to reboot or shut down:
      
        general protection fault: 0000 [#1] PREEMPT SMP
        Modules linked in: i915 i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm netconsole configfs binfmt_misc iTCO_wdt psmouse pcspkr snd_hda_codec_idt e100 coretemp hwmon snd_hda_codec_generic i2c_i801 mii i2c_smbus lpc_ich mfd_core snd_hda_intel uhci_hcd snd_hda_codec snd_hwdep snd_hda_core ehci_pci 8250 ehci_hcd snd_pcm 8250_base usbcore evdev serial_core usb_common parport_pc parport snd_timer snd soundcore
        CPU: 0 PID: 3070 Comm: reboot Not tainted 4.8.0-rc1-perf-dirty #69
        Hardware name:                  /D946GZIS, BIOS TS94610J.86A.0087.2007.1107.1049 11/07/2007
        task: ffff88012a0b4080 task.stack: ffff880123850000
        RIP: 0010:[<ffffffff81003c92>]  [<ffffffff81003c92>] x86_perf_event_update+0x52/0xc0
        RSP: 0018:ffff880123853b60  EFLAGS: 00010087
        RAX: 0000000000000001 RBX: ffff88012fc0a3c0 RCX: 000000000000001e
        RDX: 0000000000000000 RSI: 0000000040000000 RDI: ffff88012b014800
        RBP: ffff880123853b88 R08: ffffffffffffffff R09: 0000000000000000
        R10: ffffea0004a012c0 R11: ffffea0004acedc0 R12: ffffffff80000001
        R13: ffff88012b0149c0 R14: ffff88012b014800 R15: 0000000000000018
        FS:  00007f8b155cd700(0000) GS:ffff88012fc00000(0000) knlGS:0000000000000000
        CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
        CR2: 00007f8b155f5000 CR3: 000000012a2d7000 CR4: 00000000000006f0
        Stack:
         ffff88012fc0a3c0 ffff88012b014800 0000000000000004 0000000000000001
         ffff88012fc1b750 ffff880123853bb0 ffffffff81003d59 ffff88012b014800
         ffff88012fc0a3c0 ffff88012b014800 ffff880123853bd8 ffffffff81003e13
        Call Trace:
         [<ffffffff81003d59>] x86_pmu_stop+0x59/0xd0
         [<ffffffff81003e13>] x86_pmu_del+0x43/0x140
         [<ffffffff8111705d>] event_sched_out.isra.105+0xbd/0x260
         [<ffffffff8111738d>] __perf_remove_from_context+0x2d/0xb0
         [<ffffffff8111745d>] __perf_event_exit_context+0x4d/0x70
         [<ffffffff810c8826>] generic_exec_single+0xb6/0x140
         [<ffffffff81117410>] ? __perf_remove_from_context+0xb0/0xb0
         [<ffffffff81117410>] ? __perf_remove_from_context+0xb0/0xb0
         [<ffffffff810c898f>] smp_call_function_single+0xdf/0x140
         [<ffffffff81113d27>] perf_event_exit_cpu_context+0x87/0xc0
         [<ffffffff81113d73>] perf_reboot+0x13/0x40
         [<ffffffff8107578a>] notifier_call_chain+0x4a/0x70
         [<ffffffff81075ad7>] __blocking_notifier_call_chain+0x47/0x60
         [<ffffffff81075b06>] blocking_notifier_call_chain+0x16/0x20
         [<ffffffff81076a1d>] kernel_restart_prepare+0x1d/0x40
         [<ffffffff81076ae2>] kernel_restart+0x12/0x60
         [<ffffffff81076d56>] SYSC_reboot+0xf6/0x1b0
         [<ffffffff811a823c>] ? mntput_no_expire+0x2c/0x1b0
         [<ffffffff811a83e4>] ? mntput+0x24/0x40
         [<ffffffff811894fc>] ? __fput+0x16c/0x1e0
         [<ffffffff811895ae>] ? ____fput+0xe/0x10
         [<ffffffff81072fc3>] ? task_work_run+0x83/0xa0
         [<ffffffff81001623>] ? exit_to_usermode_loop+0x53/0xc0
         [<ffffffff8100105a>] ? trace_hardirqs_on_thunk+0x1a/0x1c
         [<ffffffff81076e6e>] SyS_reboot+0xe/0x10
         [<ffffffff814c4ba5>] entry_SYSCALL_64_fastpath+0x18/0xa3
        Code: 7c 4c 8d af c0 01 00 00 49 89 fe eb 10 48 09 c2 4c 89 e0 49 0f b1 55 00 4c 39 e0 74 35 4d 8b a6 c0 01 00 00 41 8b 8e 60 01 00 00 <0f> 33 8b 35 6e 02 8c 00 48 c1 e2 20 85 f6 7e d2 48 89 d3 89 cf
        RIP  [<ffffffff81003c92>] x86_perf_event_update+0x52/0xc0
         RSP <ffff880123853b60>
        ---[ end trace 7ec95181faf211be ]---
        note: reboot[3070] exited with preempt_count 2
      
      Cc: Borislav Petkov <bp@suse.de>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@kernel.org>
      Fixes: f5967101 ("x86/hweight: Get rid of the special calling convention")
      Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      65ea11ec
    • Dave Airlie's avatar
      Merge branch 'drm-next-4.8' of git://people.freedesktop.org/~agd5f/linux into drm-next · 4872850a
      Dave Airlie authored
      A few fixes for amdgpu and ttm for 4.8
      - fix a ttm regression caused by the new pipelining code
      - fixes for mullins on amdgpu
      - updated golden settings for amdgpu
      
      * 'drm-next-4.8' of git://people.freedesktop.org/~agd5f/linux:
        drm/ttm: Wait for a BO to become idle before unbinding it from GTT
        drm/amdgpu: update golden setting of polaris10
        drm/amdgpu: update golden setting of stoney
        drm/amdgpu: update golden setting of polaris11
        drm/amdgpu: update golden setting of carrizo
        drm/amdgpu: update golden setting of iceland
        drm/amd/amdgpu: change pptable output format from ASCII to binary
        drm/amdgpu/ci: add mullins to default case for smc ucode
        drm/amdgpu/gmc7: add missing mullins case
      4872850a
    • Dave Airlie's avatar
      Merge tag 'drm-intel-next-fixes-2016-08-05' of... · e8285cec
      Dave Airlie authored
      Merge tag 'drm-intel-next-fixes-2016-08-05' of git://anongit.freedesktop.org/drm-intel into drm-next
      
      3 intel fixes.
      
      * tag 'drm-intel-next-fixes-2016-08-05' of git://anongit.freedesktop.org/drm-intel:
        drm/i915/fbdev: Check for the framebuffer before use
        drm/i915: Never fully mask the the EI up rps interrupt on SNB/IVB
        drm/i915: Wait up to 3ms for the pcu to ack the cdclk change request on SKL
      e8285cec
    • Daniel Vetter's avatar
      drm: Paper over locking inversion after registration rework · 5c6c201c
      Daniel Vetter authored
      drm_connector_register_all requires a few too many locks because our
      connector_list locking is busted. Add another FIXME+hack to work
      around this. This should address the below lockdep splat:
      
      ======================================================
      [ INFO: possible circular locking dependency detected ]
      4.7.0-rc5+ #524 Tainted: G           O
      -------------------------------------------------------
      kworker/u8:0/6 is trying to acquire lock:
       (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
      
      but task is already holding lock:
       ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810ac195>] __blocking_notifier_call_chain+0x35/0x70
      
      which lock already depends on the new lock.
      
      the existing dependency chain (in reverse order) is:
      
      -> #1 ((fb_notifier_list).rwsem){++++.+}:
             [<ffffffff810df611>] lock_acquire+0xb1/0x200
             [<ffffffff819a55b4>] down_write+0x44/0x80
             [<ffffffff810abf91>] blocking_notifier_chain_register+0x21/0xb0
             [<ffffffff814c7448>] fb_register_client+0x18/0x20
             [<ffffffff814c6c86>] backlight_device_register+0x136/0x260
             [<ffffffffa0127eb2>] intel_backlight_device_register+0xa2/0x160 [i915]
             [<ffffffffa00f46be>] intel_connector_register+0xe/0x10 [i915]
             [<ffffffffa0112bfb>] intel_dp_connector_register+0x1b/0x80 [i915]
             [<ffffffff8159dfea>] drm_connector_register+0x4a/0x80
             [<ffffffff8159fe44>] drm_connector_register_all+0x64/0xf0
             [<ffffffff815a2a64>] drm_modeset_register_all+0x174/0x1c0
             [<ffffffff81599b72>] drm_dev_register+0xc2/0xd0
             [<ffffffffa00621d7>] i915_driver_load+0x1547/0x2200 [i915]
             [<ffffffffa006d80f>] i915_pci_probe+0x4f/0x70 [i915]
             [<ffffffff814a2135>] local_pci_probe+0x45/0xa0
             [<ffffffff814a349b>] pci_device_probe+0xdb/0x130
             [<ffffffff815c07e3>] driver_probe_device+0x223/0x440
             [<ffffffff815c0ad5>] __driver_attach+0xd5/0x100
             [<ffffffff815be386>] bus_for_each_dev+0x66/0xa0
             [<ffffffff815c002e>] driver_attach+0x1e/0x20
             [<ffffffff815bf9be>] bus_add_driver+0x1ee/0x280
             [<ffffffff815c1810>] driver_register+0x60/0xe0
             [<ffffffff814a1a10>] __pci_register_driver+0x60/0x70
             [<ffffffffa01a905b>] i915_init+0x5b/0x62 [i915]
             [<ffffffff8100042d>] do_one_initcall+0x3d/0x150
             [<ffffffff811a935b>] do_init_module+0x5f/0x1d9
             [<ffffffff81124416>] load_module+0x20e6/0x27e0
             [<ffffffff81124d63>] SYSC_finit_module+0xc3/0xf0
             [<ffffffff81124dae>] SyS_finit_module+0xe/0x10
             [<ffffffff819a83a9>] entry_SYSCALL_64_fastpath+0x1c/0xac
      
      -> #0 (&dev->mode_config.mutex){+.+.+.}:
             [<ffffffff810df0ac>] __lock_acquire+0x10fc/0x1260
             [<ffffffff810df611>] lock_acquire+0xb1/0x200
             [<ffffffff819a3097>] mutex_lock_nested+0x67/0x3c0
             [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
             [<ffffffff8158f79b>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2b/0x80
             [<ffffffff8158f81d>] drm_fb_helper_set_par+0x2d/0x50
             [<ffffffffa0105f7a>] intel_fbdev_set_par+0x1a/0x60 [i915]
             [<ffffffff814c13c6>] fbcon_init+0x586/0x610
             [<ffffffff8154d16a>] visual_init+0xca/0x130
             [<ffffffff8154e611>] do_bind_con_driver+0x1c1/0x3a0
             [<ffffffff8154eaf6>] do_take_over_console+0x116/0x180
             [<ffffffff814bd3a7>] do_fbcon_takeover+0x57/0xb0
             [<ffffffff814c1e48>] fbcon_event_notify+0x658/0x750
             [<ffffffff810abcae>] notifier_call_chain+0x3e/0xb0
             [<ffffffff810ac1ad>] __blocking_notifier_call_chain+0x4d/0x70
             [<ffffffff810ac1e6>] blocking_notifier_call_chain+0x16/0x20
             [<ffffffff814c748b>] fb_notifier_call_chain+0x1b/0x20
             [<ffffffff814c86b1>] register_framebuffer+0x251/0x330
             [<ffffffff8158fa9f>] drm_fb_helper_initial_config+0x25f/0x3f0
             [<ffffffffa0106b48>] intel_fbdev_initial_config+0x18/0x30 [i915]
             [<ffffffff810adfd8>] async_run_entry_fn+0x48/0x150
             [<ffffffff810a3947>] process_one_work+0x1e7/0x750
             [<ffffffff810a3efb>] worker_thread+0x4b/0x4f0
             [<ffffffff810aad4f>] kthread+0xef/0x110
             [<ffffffff819a85ef>] ret_from_fork+0x1f/0x40
      
      other info that might help us debug this:
      
       Possible unsafe locking scenario:
      
             CPU0                    CPU1
             ----                    ----
        lock((fb_notifier_list).rwsem);
                                     lock(&dev->mode_config.mutex);
                                     lock((fb_notifier_list).rwsem);
        lock(&dev->mode_config.mutex);
      
       *** DEADLOCK ***
      
      6 locks held by kworker/u8:0/6:
       #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff810a38c9>] process_one_work+0x169/0x750
       #1:  ((&entry->work)){+.+.+.}, at: [<ffffffff810a38c9>] process_one_work+0x169/0x750
       #2:  (registration_lock){+.+.+.}, at: [<ffffffff814c8487>] register_framebuffer+0x27/0x330
       #3:  (console_lock){+.+.+.}, at: [<ffffffff814c86ce>] register_framebuffer+0x26e/0x330
       #4:  (&fb_info->lock){+.+.+.}, at: [<ffffffff814c78dd>] lock_fb_info+0x1d/0x40
       #5:  ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810ac195>] __blocking_notifier_call_chain+0x35/0x70
      
      stack backtrace:
      CPU: 2 PID: 6 Comm: kworker/u8:0 Tainted: G           O    4.7.0-rc5+ #524
      Hardware name: Intel Corp. Broxton P/NOTEBOOK, BIOS APLKRVPA.X64.0138.B33.1606250842 06/25/2016
      Workqueue: events_unbound async_run_entry_fn
       0000000000000000 ffff8800758577f0 ffffffff814507a5 ffffffff828b9900
       ffffffff828b9900 ffff880075857830 ffffffff810dc6fa ffff880075857880
       ffff88007584d688 0000000000000005 0000000000000006 ffff88007584d6b0
      Call Trace:
       [<ffffffff814507a5>] dump_stack+0x67/0x92
       [<ffffffff810dc6fa>] print_circular_bug+0x1aa/0x200
       [<ffffffff810df0ac>] __lock_acquire+0x10fc/0x1260
       [<ffffffff810df611>] lock_acquire+0xb1/0x200
       [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
       [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
       [<ffffffff819a3097>] mutex_lock_nested+0x67/0x3c0
       [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
       [<ffffffff810fa85f>] ? rcu_read_lock_sched_held+0x7f/0x90
       [<ffffffff81208218>] ? kmem_cache_alloc_trace+0x248/0x2b0
       [<ffffffff815afdc5>] ? drm_modeset_lock_all+0x25/0x120
       [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
       [<ffffffff8158f79b>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2b/0x80
       [<ffffffff8158f81d>] drm_fb_helper_set_par+0x2d/0x50
       [<ffffffffa0105f7a>] intel_fbdev_set_par+0x1a/0x60 [i915]
       [<ffffffff814c13c6>] fbcon_init+0x586/0x610
       [<ffffffff8154d16a>] visual_init+0xca/0x130
       [<ffffffff8154e611>] do_bind_con_driver+0x1c1/0x3a0
       [<ffffffff8154eaf6>] do_take_over_console+0x116/0x180
       [<ffffffff814bd3a7>] do_fbcon_takeover+0x57/0xb0
       [<ffffffff814c1e48>] fbcon_event_notify+0x658/0x750
       [<ffffffff810abcae>] notifier_call_chain+0x3e/0xb0
       [<ffffffff810ac1ad>] __blocking_notifier_call_chain+0x4d/0x70
       [<ffffffff810ac1e6>] blocking_notifier_call_chain+0x16/0x20
       [<ffffffff814c748b>] fb_notifier_call_chain+0x1b/0x20
       [<ffffffff814c86b1>] register_framebuffer+0x251/0x330
       [<ffffffff815b7e8d>] ? vga_switcheroo_client_fb_set+0x5d/0x70
       [<ffffffff8158fa9f>] drm_fb_helper_initial_config+0x25f/0x3f0
       [<ffffffffa0106b48>] intel_fbdev_initial_config+0x18/0x30 [i915]
       [<ffffffff810adfd8>] async_run_entry_fn+0x48/0x150
       [<ffffffff810a3947>] process_one_work+0x1e7/0x750
       [<ffffffff810a38c9>] ? process_one_work+0x169/0x750
       [<ffffffff810a3efb>] worker_thread+0x4b/0x4f0
       [<ffffffff810a3eb0>] ? process_one_work+0x750/0x750
       [<ffffffff810aad4f>] kthread+0xef/0x110
       [<ffffffff819a85ef>] ret_from_fork+0x1f/0x40
       [<ffffffff810aac60>] ? kthread_stop+0x2e0/0x2e0
      
      v2: Rebase onto the right branch (hand-editing patches ftw) and add more
      reporters.
      Reported-by: default avatarImre Deak <imre.deak@intel.com>
      Cc: Imre Deak <imre.deak@intel.com>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Acked-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
      Reported-by: default avatarJiri Kosina <jikos@kernel.org>
      Cc: Jiri Kosina <jikos@kernel.org>
      Signed-off-by: default avatarDaniel Vetter <daniel.vetter@intel.com>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      5c6c201c