1. 10 Sep, 2018 6 commits
    • Vincent Guittot's avatar
      sched/fair: Fix scale_rt_capacity() for SMT · 287cdaac
      Vincent Guittot authored
      Since commit:
      
        523e979d ("sched/core: Use PELT for scale_rt_capacity()")
      
      scale_rt_capacity() returns the remaining capacity and not a scale factor
      to apply on cpu_capacity_orig. arch_scale_cpu() is directly called by
      scale_rt_capacity() so we must take the sched_domain argument.
      Reported-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
      Signed-off-by: default avatarVincent Guittot <vincent.guittot@linaro.org>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Reviewed-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Fixes: 523e979d ("sched/core: Use PELT for scale_rt_capacity()")
      Link: http://lkml.kernel.org/r/20180904093626.GA23936@linaro.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      287cdaac
    • Steve Muckle's avatar
      sched/fair: Fix vruntime_normalized() for remote non-migration wakeup · d0cdb3ce
      Steve Muckle authored
      When a task which previously ran on a given CPU is remotely queued to
      wake up on that same CPU, there is a period where the task's state is
      TASK_WAKING and its vruntime is not normalized. This is not accounted
      for in vruntime_normalized() which will cause an error in the task's
      vruntime if it is switched from the fair class during this time.
      
      For example if it is boosted to RT priority via rt_mutex_setprio(),
      rq->min_vruntime will not be subtracted from the task's vruntime but
      it will be added again when the task returns to the fair class. The
      task's vruntime will have been erroneously doubled and the effective
      priority of the task will be reduced.
      
      Note this will also lead to inflation of all vruntimes since the doubled
      vruntime value will become the rq's min_vruntime when other tasks leave
      the rq. This leads to repeated doubling of the vruntime and priority
      penalty.
      
      Fix this by recognizing a WAKING task's vruntime as normalized only if
      sched_remote_wakeup is true. This indicates a migration, in which case
      the vruntime would have been normalized in migrate_task_rq_fair().
      
      Based on a similar patch from John Dias <joaodias@google.com>.
      Suggested-by: default avatarPeter Zijlstra <peterz@infradead.org>
      Tested-by: default avatarDietmar Eggemann <dietmar.eggemann@arm.com>
      Signed-off-by: default avatarSteve Muckle <smuckle@google.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Chris Redpath <Chris.Redpath@arm.com>
      Cc: John Dias <joaodias@google.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Miguel de Dios <migueldedios@google.com>
      Cc: Morten Rasmussen <Morten.Rasmussen@arm.com>
      Cc: Patrick Bellasi <Patrick.Bellasi@arm.com>
      Cc: Paul Turner <pjt@google.com>
      Cc: Quentin Perret <quentin.perret@arm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Todd Kjos <tkjos@google.com>
      Cc: kernel-team@android.com
      Fixes: b5179ac7 ("sched/fair: Prepare to fix fairness problems on migration")
      Link: http://lkml.kernel.org/r/20180831224217.169476-1-smuckle@google.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      d0cdb3ce
    • Vincent Guittot's avatar
      sched/pelt: Fix update_blocked_averages() for RT and DL classes · 12b04875
      Vincent Guittot authored
      update_blocked_averages() is called to periodiccally decay the stalled load
      of idle CPUs and to sync all loads before running load balance.
      
      When cfs rq is idle, it trigs a load balance during pick_next_task_fair()
      in order to potentially pull tasks and to use this newly idle CPU. This
      load balance happens whereas prev task from another class has not been put
      and its utilization updated yet. This may lead to wrongly account running
      time as idle time for RT or DL classes.
      
      Test that no RT or DL task is running when updating their utilization in
      update_blocked_averages().
      
      We still update RT and DL utilization instead of simply skipping them to
      make sure that all metrics are synced when used during load balance.
      Signed-off-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: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Fixes: 371bf427 ("sched/rt: Add rt_rq utilization tracking")
      Fixes: 3727e0e1 ("sched/dl: Add dl_rq utilization tracking")
      Link: http://lkml.kernel.org/r/1535728975-22799-1-git-send-email-vincent.guittot@linaro.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      12b04875
    • Srikar Dronamraju's avatar
      sched/topology: Set correct NUMA topology type · e5e96faf
      Srikar Dronamraju authored
      With the following commit:
      
        051f3ca0 ("sched/topology: Introduce NUMA identity node sched domain")
      
      the scheduler introduced a new NUMA level. However this leads to the NUMA topology
      on 2 node systems to not be marked as NUMA_DIRECT anymore.
      
      After this commit, it gets reported as NUMA_BACKPLANE, because
      sched_domains_numa_level is now 2 on 2 node systems.
      
      Fix this by allowing setting systems that have up to 2 NUMA levels as
      NUMA_DIRECT.
      
      While here remove code that assumes that level can be 0.
      Signed-off-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Andre Wild <wild@linux.vnet.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rik van Riel <riel@surriel.com>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
      Fixes: 051f3ca0 "Introduce NUMA identity node sched domain"
      Link: http://lkml.kernel.org/r/1533920419-17410-1-git-send-email-srikar@linux.vnet.ibm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      e5e96faf
    • Jiada Wang's avatar
      sched/debug: Fix potential deadlock when writing to sched_features · e73e8197
      Jiada Wang authored
      The following lockdep report can be triggered by writing to /sys/kernel/debug/sched_features:
      
        ======================================================
        WARNING: possible circular locking dependency detected
        4.18.0-rc6-00152-gcd3f77d7-dirty #18 Not tainted
        ------------------------------------------------------
        sh/3358 is trying to acquire lock:
        000000004ad3989d (cpu_hotplug_lock.rw_sem){++++}, at: static_key_enable+0x14/0x30
        but task is already holding lock:
        00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428
        which lock already depends on the new lock.
        the existing dependency chain (in reverse order) is:
        -> #3 (&sb->s_type->i_mutex_key#3){+.+.}:
               lock_acquire+0xb8/0x148
               down_write+0xac/0x140
               start_creating+0x5c/0x168
               debugfs_create_dir+0x18/0x220
               opp_debug_register+0x8c/0x120
               _add_opp_dev+0x104/0x1f8
               dev_pm_opp_get_opp_table+0x174/0x340
               _of_add_opp_table_v2+0x110/0x760
               dev_pm_opp_of_add_table+0x5c/0x240
               dev_pm_opp_of_cpumask_add_table+0x5c/0x100
               cpufreq_init+0x160/0x430
               cpufreq_online+0x1cc/0xe30
               cpufreq_add_dev+0x78/0x198
               subsys_interface_register+0x168/0x270
               cpufreq_register_driver+0x1c8/0x278
               dt_cpufreq_probe+0xdc/0x1b8
               platform_drv_probe+0xb4/0x168
               driver_probe_device+0x318/0x4b0
               __device_attach_driver+0xfc/0x1f0
               bus_for_each_drv+0xf8/0x180
               __device_attach+0x164/0x200
               device_initial_probe+0x10/0x18
               bus_probe_device+0x110/0x178
               device_add+0x6d8/0x908
               platform_device_add+0x138/0x3d8
               platform_device_register_full+0x1cc/0x1f8
               cpufreq_dt_platdev_init+0x174/0x1bc
               do_one_initcall+0xb8/0x310
               kernel_init_freeable+0x4b8/0x56c
               kernel_init+0x10/0x138
               ret_from_fork+0x10/0x18
        -> #2 (opp_table_lock){+.+.}:
               lock_acquire+0xb8/0x148
               __mutex_lock+0x104/0xf50
               mutex_lock_nested+0x1c/0x28
               _of_add_opp_table_v2+0xb4/0x760
               dev_pm_opp_of_add_table+0x5c/0x240
               dev_pm_opp_of_cpumask_add_table+0x5c/0x100
               cpufreq_init+0x160/0x430
               cpufreq_online+0x1cc/0xe30
               cpufreq_add_dev+0x78/0x198
               subsys_interface_register+0x168/0x270
               cpufreq_register_driver+0x1c8/0x278
               dt_cpufreq_probe+0xdc/0x1b8
               platform_drv_probe+0xb4/0x168
               driver_probe_device+0x318/0x4b0
               __device_attach_driver+0xfc/0x1f0
               bus_for_each_drv+0xf8/0x180
               __device_attach+0x164/0x200
               device_initial_probe+0x10/0x18
               bus_probe_device+0x110/0x178
               device_add+0x6d8/0x908
               platform_device_add+0x138/0x3d8
               platform_device_register_full+0x1cc/0x1f8
               cpufreq_dt_platdev_init+0x174/0x1bc
               do_one_initcall+0xb8/0x310
               kernel_init_freeable+0x4b8/0x56c
               kernel_init+0x10/0x138
               ret_from_fork+0x10/0x18
        -> #1 (subsys mutex#6){+.+.}:
               lock_acquire+0xb8/0x148
               __mutex_lock+0x104/0xf50
               mutex_lock_nested+0x1c/0x28
               subsys_interface_register+0xd8/0x270
               cpufreq_register_driver+0x1c8/0x278
               dt_cpufreq_probe+0xdc/0x1b8
               platform_drv_probe+0xb4/0x168
               driver_probe_device+0x318/0x4b0
               __device_attach_driver+0xfc/0x1f0
               bus_for_each_drv+0xf8/0x180
               __device_attach+0x164/0x200
               device_initial_probe+0x10/0x18
               bus_probe_device+0x110/0x178
               device_add+0x6d8/0x908
               platform_device_add+0x138/0x3d8
               platform_device_register_full+0x1cc/0x1f8
               cpufreq_dt_platdev_init+0x174/0x1bc
               do_one_initcall+0xb8/0x310
               kernel_init_freeable+0x4b8/0x56c
               kernel_init+0x10/0x138
               ret_from_fork+0x10/0x18
        -> #0 (cpu_hotplug_lock.rw_sem){++++}:
               __lock_acquire+0x203c/0x21d0
               lock_acquire+0xb8/0x148
               cpus_read_lock+0x58/0x1c8
               static_key_enable+0x14/0x30
               sched_feat_write+0x314/0x428
               full_proxy_write+0xa0/0x138
               __vfs_write+0xd8/0x388
               vfs_write+0xdc/0x318
               ksys_write+0xb4/0x138
               sys_write+0xc/0x18
               __sys_trace_return+0x0/0x4
        other info that might help us debug this:
        Chain exists of:
          cpu_hotplug_lock.rw_sem --> opp_table_lock --> &sb->s_type->i_mutex_key#3
         Possible unsafe locking scenario:
               CPU0                    CPU1
               ----                    ----
          lock(&sb->s_type->i_mutex_key#3);
                                       lock(opp_table_lock);
                                       lock(&sb->s_type->i_mutex_key#3);
          lock(cpu_hotplug_lock.rw_sem);
         *** DEADLOCK ***
        2 locks held by sh/3358:
         #0: 00000000a8c4b363 (sb_writers#10){.+.+}, at: vfs_write+0x238/0x318
         #1: 00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428
        stack backtrace:
        CPU: 5 PID: 3358 Comm: sh Not tainted 4.18.0-rc6-00152-gcd3f77d7-dirty #18
        Hardware name: Renesas H3ULCB Kingfisher board based on r8a7795 ES2.0+ (DT)
        Call trace:
         dump_backtrace+0x0/0x288
         show_stack+0x14/0x20
         dump_stack+0x13c/0x1ac
         print_circular_bug.isra.10+0x270/0x438
         check_prev_add.constprop.16+0x4dc/0xb98
         __lock_acquire+0x203c/0x21d0
         lock_acquire+0xb8/0x148
         cpus_read_lock+0x58/0x1c8
         static_key_enable+0x14/0x30
         sched_feat_write+0x314/0x428
         full_proxy_write+0xa0/0x138
         __vfs_write+0xd8/0x388
         vfs_write+0xdc/0x318
         ksys_write+0xb4/0x138
         sys_write+0xc/0x18
         __sys_trace_return+0x0/0x4
      
      This is because when loading the cpufreq_dt module we first acquire
      cpu_hotplug_lock.rw_sem lock, then in cpufreq_init(), we are taking
      the &sb->s_type->i_mutex_key lock.
      
      But when writing to /sys/kernel/debug/sched_features, the
      cpu_hotplug_lock.rw_sem lock depends on the &sb->s_type->i_mutex_key lock.
      
      To fix this bug, reverse the lock acquisition order when writing to
      sched_features, this way cpu_hotplug_lock.rw_sem no longer depends on
      &sb->s_type->i_mutex_key.
      Tested-by: default avatarDietmar Eggemann <dietmar.eggemann@arm.com>
      Signed-off-by: default avatarJiada Wang <jiada_wang@mentor.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Eugeniu Rosca <erosca@de.adit-jv.com>
      Cc: George G. Davis <george_davis@mentor.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/20180731121222.26195-1-jiada_wang@mentor.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      e73e8197
    • Linus Torvalds's avatar
      Linux 4.19-rc3 · 11da3a7f
      Linus Torvalds authored
      11da3a7f
  2. 09 Sep, 2018 7 commits
  3. 08 Sep, 2018 6 commits
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm · f8f65382
      Linus Torvalds authored
      Pull KVM fixes from Radim Krčmář:
       "ARM:
         - Fix a VFP corruption in 32-bit guest
         - Add missing cache invalidation for CoW pages
         - Two small cleanups
      
        s390:
         - Fallout from the hugetlbfs support: pfmf interpretion and locking
         - VSIE: fix keywrapping for nested guests
      
        PPC:
         - Fix a bug where pages might not get marked dirty, causing guest
           memory corruption on migration
         - Fix a bug causing reads from guest memory to use the wrong guest
           real address for very large HPT guests (>256G of memory), leading
           to failures in instruction emulation.
      
        x86:
         - Fix out of bound access from malicious pv ipi hypercalls
           (introduced in rc1)
         - Fix delivery of pending interrupts when entering a nested guest,
           preventing arbitrarily late injection
         - Sanitize kvm_stat output after destroying a guest
         - Fix infinite loop when emulating a nested guest page fault and
           improve the surrounding emulation code
         - Two minor cleanups"
      
      * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (28 commits)
        KVM: LAPIC: Fix pv ipis out-of-bounds access
        KVM: nVMX: Fix loss of pending IRQ/NMI before entering L2
        arm64: KVM: Remove pgd_lock
        KVM: Remove obsolete kvm_unmap_hva notifier backend
        arm64: KVM: Only force FPEXC32_EL2.EN if trapping FPSIMD
        KVM: arm/arm64: Clean dcache to PoC when changing PTE due to CoW
        KVM: s390: Properly lock mm context allow_gmap_hpage_1m setting
        KVM: s390: vsie: copy wrapping keys to right place
        KVM: s390: Fix pfmf and conditional skey emulation
        tools/kvm_stat: re-animate display of dead guests
        tools/kvm_stat: indicate dead guests as such
        tools/kvm_stat: handle guest removals more gracefully
        tools/kvm_stat: don't reset stats when setting PID filter for debugfs
        tools/kvm_stat: fix updates for dead guests
        tools/kvm_stat: fix handling of invalid paths in debugfs provider
        tools/kvm_stat: fix python3 issues
        KVM: x86: Unexport x86_emulate_instruction()
        KVM: x86: Rename emulate_instruction() to kvm_emulate_instruction()
        KVM: x86: Do not re-{try,execute} after failed emulation in L2
        KVM: x86: Default to not allowing emulation retry in kvm_mmu_page_fault
        ...
      f8f65382
    • Linus Torvalds's avatar
      Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc · 0f3aa48a
      Linus Torvalds authored
      Pull ARM SoC fixes from Olof Johansson:
       "A few more fixes who have trickled in:
      
         - MMC bus width fixup for some Allwinner platforms
      
         - Fix for NULL deref in ti-aemif when no platform data is passed in
      
         - Fix div by 0 in SCMI code
      
         - Add a missing module alias in a new RPi driver"
      
      * tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
        memory: ti-aemif: fix a potential NULL-pointer dereference
        firmware: arm_scmi: fix divide by zero when sustained_perf_level is zero
        hwmon: rpi: add module alias to raspberrypi-hwmon
        arm64: allwinner: dts: h6: fix Pine H64 MMC bus width
      0f3aa48a
    • Olof Johansson's avatar
      Merge tag 'sunxi-fixes-for-4.19' of... · a132bb90
      Olof Johansson authored
      Merge tag 'sunxi-fixes-for-4.19' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into fixes
      
      Allwinner fixes for 4.19
      
      Just one fix for H6 mmc on the Pine H64: the mmc bus width was missing
      from the device tree. This was added in 4.19-rc1.
      
      * tag 'sunxi-fixes-for-4.19' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
        arm64: allwinner: dts: h6: fix Pine H64 MMC bus width
      Signed-off-by: default avatarOlof Johansson <olof@lixom.net>
      a132bb90
    • Nadav Amit's avatar
      x86/mm: Use WRITE_ONCE() when setting PTEs · 9bc4f28a
      Nadav Amit authored
      When page-table entries are set, the compiler might optimize their
      assignment by using multiple instructions to set the PTE. This might
      turn into a security hazard if the user somehow manages to use the
      interim PTE. L1TF does not make our lives easier, making even an interim
      non-present PTE a security hazard.
      
      Using WRITE_ONCE() to set PTEs and friends should prevent this potential
      security hazard.
      
      I skimmed the differences in the binary with and without this patch. The
      differences are (obviously) greater when CONFIG_PARAVIRT=n as more
      code optimizations are possible. For better and worse, the impact on the
      binary with this patch is pretty small. Skimming the code did not cause
      anything to jump out as a security hazard, but it seems that at least
      move_soft_dirty_pte() caused set_pte_at() to use multiple writes.
      Signed-off-by: default avatarNadav Amit <namit@vmware.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Sean Christopherson <sean.j.christopherson@intel.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: stable@vger.kernel.org
      Link: https://lkml.kernel.org/r/20180902181451.80520-1-namit@vmware.com
      9bc4f28a
    • Thomas Gleixner's avatar
      x86/apic/vector: Make error return value negative · 47b7360c
      Thomas Gleixner authored
      activate_managed() returns EINVAL instead of -EINVAL in case of
      error. While this is unlikely to happen, the positive return value would
      cause further malfunction at the call site.
      
      Fixes: 2db1f959 ("x86/vector: Handle managed interrupts proper")
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Cc: stable@vger.kernel.org
      47b7360c
    • Linus Torvalds's avatar
      Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux · d7b686eb
      Linus Torvalds authored
      Pull i2c fixes from Wolfram Sang:
      
       - bugfixes for uniphier, i801, and xiic drivers
      
       - ID removal (never produced) for imx
      
       - one MAINTAINER addition
      
      * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
        i2c: xiic: Record xilinx i2c with Zynq fragment
        i2c: xiic: Make the start and the byte count write atomic
        i2c: i801: fix DNV's SMBCTRL register offset
        i2c: imx-lpi2c: Remove mx8dv compatible entry
        dt-bindings: imx-lpi2c: Remove mx8dv compatible entry
        i2c: uniphier-f: issue STOP only for last message or I2C_M_STOP
        i2c: uniphier: issue STOP only for last message or I2C_M_STOP
      d7b686eb
  4. 07 Sep, 2018 21 commits