1. 22 Sep, 2018 6 commits
  2. 21 Sep, 2018 1 commit
  3. 20 Sep, 2018 1 commit
  4. 14 Sep, 2018 4 commits
    • Paolo Valente's avatar
      blok, bfq: do not plug I/O if all queues are weight-raised · c8765de0
      Paolo Valente authored
      
      
      To reduce latency for interactive and soft real-time applications, bfq
      privileges the bfq_queues containing the I/O of these
      applications. These privileged queues, referred-to as weight-raised
      queues, get a much higher share of the device throughput
      w.r.t. non-privileged queues. To preserve this higher share, the I/O
      of any non-weight-raised queue must be plugged whenever a sync
      weight-raised queue, while being served, remains temporarily empty. To
      attain this goal, bfq simply plugs any I/O (from any queue), if a sync
      weight-raised queue remains empty while in service.
      
      Unfortunately, this plugging typically lowers throughput with random
      I/O, on devices with internal queueing (because it reduces the filling
      level of the internal queues of the device).
      
      This commit addresses this issue by restricting the cases where
      plugging is performed: if a sync weight-raised queue remains empty
      while in service, then I/O plugging is performed only if some of the
      active bfq_queues are *not* weight-raised (which is actually the only
      circumstance where plugging is needed to preserve the higher share of
      the throughput of weight-raised queues). This restriction proved able
      to boost throughput in really many use cases needing only maximum
      throughput.
      Signed-off-by: default avatarPaolo Valente <paolo.valente@linaro.org>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      c8765de0
    • Paolo Valente's avatar
      block, bfq: inject other-queue I/O into seeky idle queues on NCQ flash · d0edc247
      Paolo Valente authored
      
      
      The Achilles' heel of BFQ is its failing to reach a high throughput
      with sync random I/O on flash storage with internal queueing, in case
      the processes doing I/O have differentiated weights.
      
      The cause of this failure is as follows. If at least two processes do
      sync I/O, and have a different weight from each other, then BFQ plugs
      I/O dispatching every time one of these processes, while it is being
      served, remains temporarily without pending I/O requests. This
      plugging is necessary to guarantee that every process enjoys a
      bandwidth proportional to its weight; but it empties the internal
      queue(s) of the drive. And this kills throughput with random I/O. So,
      if some processes have differentiated weights and do both sync and
      random I/O, the end result is a throughput collapse.
      
      This commit tries to counter this problem by injecting the service of
      other processes, in a controlled way, while the process in service
      happens to have no I/O. This injection is performed only if the medium
      is non rotational and performs internal queueing, and the process in
      service does random I/O (service injection might be beneficial for
      sequential I/O too, we'll work on that).
      
      As an example of the benefits of this commit, on a PLEXTOR PX-256M5S
      SSD, and with five processes having differentiated weights and doing
      sync random 4KB I/O, this commit makes the throughput with bfq grow by
      400%, from 25 to 100MB/s. This higher throughput is 10MB/s lower than
      that reached with none. As some less random I/O is added to the mix,
      the throughput becomes equal to or higher than that with none.
      
      This commit is a very first attempt to recover throughput without
      losing control, and certainly has many limitations. One is, e.g., that
      the processes whose service is injected are not chosen so as to
      distribute the extra bandwidth they receive in accordance to their
      weights. Thus there might be loss of weighted fairness in some
      cases. Anyway, this loss concerns extra service, which would not have
      been received at all without this commit. Other limitations and issues
      will probably show up with usage.
      Signed-off-by: default avatarPaolo Valente <paolo.valente@linaro.org>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      d0edc247
    • Paolo Valente's avatar
      block, bfq: correctly charge and reset entity service in all cases · cbeb869a
      Paolo Valente authored
      
      
      BFQ schedules entities (which represent either per-process queues or
      groups of queues) as a function of their timestamps. In particular, as
      a function of their (virtual) finish times. The finish time of an
      entity is computed as a function of the budget assigned to the entity,
      assuming, tentatively, that the entity, once in service, will receive
      an amount of service equal to its budget. Then, when the entity is
      expired because it finishes to be served, this finish time is updated
      as a function of the actual service received by the entity. This
      allows the entity to be correctly charged with only the service
      received, and then to be correctly re-scheduled.
      
      Yet an entity may receive service also while not being the entity in
      service (in the scheduling environment of its parent entity), for
      several reasons. If the entity remains with no backlog while receiving
      this 'unofficial' service, then it is expired. Also on such an
      expiration, the finish time of the entity should be updated to account
      for only the service actually received by the entity. Unfortunately,
      such an update is not performed for an entity expiring without being
      the entity in service.
      
      In a similar vein, the service counter of the entity in service is
      reset when the entity is expired, to be ready to be used for next
      service cycle. This reset too should be performed also in case an
      entity is expired because it remains empty after receiving service
      while not being the entity in service. But in this case the reset is
      not performed.
      
      This commit performs the above update of the finish time and reset of
      the service received, also for an entity expiring while not being the
      entity in service.
      Signed-off-by: default avatarPaolo Valente <paolo.valente@linaro.org>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      cbeb869a
    • YueHaibing's avatar
      blk-iolatency: remove set but not used variables 'changed' and 'blkiolat' · f8c0d7b1
      YueHaibing authored
      
      
      Fixes gcc '-Wunused-but-set-variable' warning:
      
      block/blk-iolatency.c: In function 'scale_change':
      block/blk-iolatency.c:301:7: warning:
       variable 'changed' set but not used [-Wunused-but-set-variable]
      
      block/blk-iolatency.c: In function 'iolatency_set_limit':
      block/blk-iolatency.c:765:24: warning:
       variable 'blkiolat' set but not used [-Wunused-but-set-variable]
      Signed-off-by: default avatarYueHaibing <yuehaibing@huawei.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      f8c0d7b1
  5. 11 Sep, 2018 1 commit
  6. 07 Sep, 2018 1 commit
  7. 06 Sep, 2018 8 commits
    • Ming Lei's avatar
      block: remove bio_rewind_iter() · 7759eb23
      Ming Lei authored
      It is pointed that bio_rewind_iter() is one very bad API[1]:
      
      1) bio size may not be restored after rewinding
      
      2) it causes some bogus change, such as 5151842b (block: reset
      bi_iter.bi_done after splitting bio)
      
      3) rewinding really makes things complicated wrt. bio splitting
      
      4) unnecessary updating of .bi_done in fast path
      
      [1] https://marc.info/?t=153549924200005&r=1&w=2
      
      
      
      So this patch takes Kent's suggestion to restore one bio into its original
      state via saving bio iterator(struct bvec_iter) in bio_integrity_prep(),
      given now bio_rewind_iter() is only used by bio integrity code.
      
      Cc: Dmitry Monakhov <dmonakhov@openvz.org>
      Cc: Hannes Reinecke <hare@suse.com>
      Suggested-by: default avatarKent Overstreet <kent.overstreet@gmail.com>
      Acked-by: default avatarKent Overstreet <kent.overstreet@gmail.com>
      Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      7759eb23
    • Kees Cook's avatar
      drbd: Convert from ahash to shash · 3d0e6375
      Kees Cook authored
      In preparing to remove all stack VLA usage from the kernel[1], this
      removes the discouraged use of AHASH_REQUEST_ON_STACK in favor of
      the smaller SHASH_DESC_ON_STACK by converting from ahash-wrapped-shash
      to direct shash. By removing a layer of indirection this both improves
      performance and reduces stack usage. The stack allocation will be made
      a fixed size in a later patch to the crypto subsystem.
      
      The bulk of the lines in this change are simple s/ahash/shash/, but the
      main logic differences are in drbd_csum_ee() and drbd_csum_bio(), which
      externalizes the page walking with k(un)map_atomic() instead of using
      scattergather.
      
      [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
      
      Acked-by: default avatarLars Ellenberg <lars.ellenberg@linbit.com>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      3d0e6375
    • Linus Torvalds's avatar
      Merge tag 'for-linus-20180906' of git://git.kernel.dk/linux-block · ca16eb34
      Linus Torvalds authored
      Pull block fixes from Jens Axboe:
       "Small collection of fixes that should go into this release. This
        contains:
      
         - Small series that fixes a race between blkcg teardown and writeback
           (Dennis Zhou)
      
         - Fix disallowing invalid block size settings from the nbd ioctl (me)
      
         - BFQ fix for a use-after-free on last release of a bfqg (Konstantin
           Khlebnikov)
      
         - Fix for the "don't warn for flush" fix (Mikulas)"
      
      * tag 'for-linus-20180906' of git://git.kernel.dk/linux-block:
        block: bfq: swap puts in bfqg_and_blkg_put
        block: don't warn when doing fsync on read-only devices
        nbd: don't allow invalid blocksize settings
        blkcg: use tryget logic when associating a blkg with a bio
        blkcg: delay blkg destruction until after writeback has finished
        Revert "blk-throttle: fix race between blkcg_bio_issue_check() and cgroup_rmdir()"
      ca16eb34
    • Konstantin Khlebnikov's avatar
      block: bfq: swap puts in bfqg_and_blkg_put · d5274b3c
      Konstantin Khlebnikov authored
      Fix trivial use-after-free. This could be last reference to bfqg.
      
      Fixes: 8f9bebc3
      
       ("block, bfq: access and cache blkg data only when safe")
      Acked-by: default avatarPaolo Valente <paolo.valente@linaro.org>
      Signed-off-by: default avatarKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      d5274b3c
    • Linus Torvalds's avatar
      Merge tag 'apparmor-pr-2018-09-06' of... · db44bf4b
      Linus Torvalds authored
      Merge tag 'apparmor-pr-2018-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor
      
      Pull apparmor fix from John Johansen:
       "A fix for an issue syzbot discovered last week:
      
         - Fix for bad debug check when converting secids to secctx"
      
      * tag 'apparmor-pr-2018-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
        apparmor: fix bad debug check in apparmor_secid_to_secctx()
      db44bf4b
    • Linus Torvalds's avatar
      Merge tag 'trace-v4.19-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace · be65e259
      Linus Torvalds authored
      Pull tracing fixes from Steven Rostedt:
       "This fixes two annoying bugs:
      
         - The first one is a side effect caused by using SRCU for rcuidle
           tracepoints. It seems that the perf was depending on the rcuidle
           tracepoints to make RCU watch when it wasn't.
      
           The real fix will be to have perf use SRCU instead of depending on
           RCU watching, but that can't be done until SRCU is safe to use in
           NMI context (Paul's working on that).
      
         - The second bug fix is for a bug that's been periodically making my
           tests fail randomly for some time. I haven't had time to track it
           down, but finally have. It has to do with stressing NMIs (via perf)
           while enabling or disabling ftrace function handling with lockdep
           enabled.
      
           If an interrupt happens and just as it returns, it sets lockdep
           back to "interrupts enabled" but before it returns an NMI is
           triggered, and if this happens while printk_nmi_enter has a
           breakpoint attached to it (because ftrace is converting it to or
           from nop to call fentry), the breakpoint trap also calls into
           lockdep, and since returning from the NMI to a interrupt handler,
           interrupts were disabled when the NMI went off, lockdep keeps its
           state as interrupts disabled when it returns back from the
           interrupt handler where interrupts are enabled.
      
           This causes lockdep_assert_irqs_enabled() to trigger a false
           positive"
      
      * tag 'trace-v4.19-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
        printk/tracing: Do not trace printk_nmi_enter()
        tracing: Add back in rcu_irq_enter/exit_irqson() for rcuidle tracepoints
      be65e259
    • Linus Torvalds's avatar
      Merge tag 'for-4.19-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux · 5404525b
      Linus Torvalds authored
      Pull btrfs fixes from David Sterba:
      
       - fix for improper fsync after hardlink
      
       - fix for a corruption during file deduplication
      
       - use after free fixes
      
       - RCU warning fix
      
       - fix for buffered write to nodatacow file
      
      * tag 'for-4.19-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
        btrfs: Fix suspicious RCU usage warning in btrfs_debug_in_rcu
        btrfs: use after free in btrfs_quota_enable
        btrfs: btrfs_shrink_device should call commit transaction at the end
        btrfs: fix qgroup_free wrong num_bytes in btrfs_subvolume_reserve_metadata
        Btrfs: fix data corruption when deduplicating between different files
        Btrfs: sync log after logging new name
        Btrfs: fix unexpected failure of nocow buffered writes after snapshotting when low on space
      5404525b
    • Steven Rostedt (VMware)'s avatar
      printk/tracing: Do not trace printk_nmi_enter() · d1c392c9
      Steven Rostedt (VMware) authored
      I hit the following splat in my tests:
      
      ------------[ cut here ]------------
      IRQs not enabled as expected
      WARNING: CPU: 3 PID: 0 at kernel/time/tick-sched.c:982 tick_nohz_idle_enter+0x44/0x8c
      Modules linked in: ip6t_REJECT nf_reject_ipv6 ip6table_filter ip6_tables ipv6
      CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.19.0-rc2-test+ #2
      Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014
      EIP: tick_nohz_idle_enter+0x44/0x8c
      Code: ec 05 00 00 00 75 26 83 b8 c0 05 00 00 00 75 1d 80 3d d0 36 3e c1 00
      75 14 68 94 63 12 c1 c6 05 d0 36 3e c1 01 e8 04 ee f8 ff <0f> 0b 58 fa bb a0
      e5 66 c1 e8 25 0f 04 00 64 03 1d 28 31 52 c1 8b
      EAX: 0000001c EBX: f26e7f8c ECX: 00000006 EDX: 00000007
      ESI: f26dd1c0 EDI: 00000000 EBP: f26e7f40 ESP: f26e7f38
      DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010296
      CR0: 80050033 CR2: 0813c6b0 CR3: 2f342000 CR4: 001406f0
      Call Trace:
       do_idle+0x33/0x202
       cpu_startup_entry+0x61/0x63
       start_secondary+0x18e/0x1ed
       startup_32_smp+0x164/0x168
      irq event stamp: 18773830
      hardirqs last  enabled at (18773829): [<c040150c>] trace_hardirqs_on_thunk+0xc/0x10
      hardirqs last disabled at (18773830): [<c040151c>] trace_hardirqs_off_thunk+0xc/0x10
      softirqs last  enabled at (18773824): [<c0ddaa6f>] __do_softirq+0x25f/0x2bf
      softirqs last disabled at (18773767): [<c0416bbe>] call_on_stack+0x45/0x4b
      ---[ end trace b7c64aa79e17954a ]---
      
      After a bit of debugging, I found what was happening. This would trigger
      when performing "perf" with a high NMI interrupt rate, while enabling and
      disabling function tracer. Ftrace uses breakpoints to convert the nops at
      the start of functions to calls to the function trampolines. The breakpoint
      traps disable interrupts and this makes calls into lockdep via the
      trace_hardirqs_off_thunk in the entry.S code. What happens is the following:
      
        do_idle {
      
          [interrupts enabled]
      
          <interrupt> [interrupts disabled]
      	TRACE_IRQS_OFF [lockdep says irqs off]
      	[...]
      	TRACE_IRQS_IRET
      	    test if pt_regs say return to interrupts enabled [yes]
      	    TRACE_IRQS_ON [lockdep says irqs are on]
      
      	    <nmi>
      		nmi_enter() {
      		    printk_nmi_enter() [traced by ftrace]
      		    [ hit ftrace breakpoint ]
      		    <breakpoint exception>
      			TRACE_IRQS_OFF [lockdep says irqs off]
      			[...]
      			TRACE_IRQS_IRET [return from breakpoint]
      			   test if pt_regs say interrupts enabled [no]
      			   [iret back to interrupt]
      	   [iret back to code]
      
          tick_nohz_idle_enter() {
      
      	lockdep_assert_irqs_enabled() [lockdep say no!]
      
      Although interrupts are indeed enabled, lockdep thinks it is not, and since
      we now do asserts via lockdep, it gives a false warning. The issue here is
      that printk_nmi_enter() is called before lockdep_off(), which disables
      lockdep (for this reason) in NMIs. By simply not allowing ftrace to see
      printk_nmi_enter() (via notrace annotation) we keep lockdep from getting
      confused.
      
      Cc: stable@vger.kernel.org
      Fixes: 42a0bb3f
      
       ("printk/nmi: generic solution for safe printk in NMI")
      Acked-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
      Acked-by: default avatarPetr Mladek <pmladek@suse.com>
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      d1c392c9
  8. 05 Sep, 2018 7 commits
    • Mikulas Patocka's avatar
      block: don't warn when doing fsync on read-only devices · 8b2ded1c
      Mikulas Patocka authored
      It is possible to call fsync on a read-only handle (for example, fsck.ext2
      does it when doing read-only check), and this call results in kernel
      warning.
      
      The patch b089cfd9
      
       ("block: don't warn for flush on read-only device")
      attempted to disable the warning, but it is buggy and it doesn't
      (op_is_flush tests flags, but bio_op strips off the flags).
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Fixes: 721c7fc7
      
       ("block: fail op_is_write() requests to read-only partitions")
      Cc: stable@vger.kernel.org	# 4.18
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      8b2ded1c
    • Linus Torvalds's avatar
      Merge tag 'gpio-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio · b36fdc68
      Linus Torvalds authored
      Pull GPIO fixes from Linus Walleij:
       "Some GPIO fixes. The ACPI stuff is probably the most annoying for
        users that get fixed this time.
      
         - Atomic contexts, cansleep* calls and such fastpath/slopwpath
           things.
      
         - Defer ACPI event handler registration to late_initcall() so IRQs do
           not fire in our face before other drivers have a chance to register
           handlers.
      
         - Race condition if a consumer requests a GPIO after
           gpiochip_add_data_with_key() but before of_gpiochip_add()
      
         - Probe errorpath in the dwapb driver"
      
      * tag 'gpio-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
        gpio: Fix crash due to registration race
        gpio: dwapb: Fix error handling in dwapb_gpio_probe()
        gpiolib-acpi: Register GpioInt ACPI event handlers from a late_initcall
        gpiolib: acpi: Switch to cansleep version of GPIO library call
        gpio: adp5588: Fix sleep-in-atomic-context bug
      b36fdc68
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · f4697d9a
      Linus Torvalds authored
      Pull SCSI fixes from James Bottomley:
       "A set of very minor fixes and a couple of reverts to fix a major
        problem (the attempt to change the busy count causes a hang when
        attempting to change the drive cache type)"
      
      * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        scsi: aacraid: fix a signedness bug
        Revert "scsi: core: avoid host-wide host_busy counter for scsi_mq"
        Revert "scsi: core: fix scsi_host_queue_ready"
        scsi: libata: Add missing newline at end of file
        scsi: target: iscsi: cxgbit: use pr_debug() instead of pr_info()
        scsi: hpsa: limit transfer length to 1MB, not 512kB
        scsi: lpfc: Correct MDS diag and nvmet configuration
        scsi: lpfc: Default fdmi_on to on
        scsi: csiostor: fix incorrect port capabilities
        scsi: csiostor: add a check for NULL pointer after kmalloc()
        scsi: documentation: add scsi_mod.use_blk_mq to scsi-parameters
        scsi: core: Update SCSI_MQ_DEFAULT help text to match default
      f4697d9a
    • Linus Torvalds's avatar
      Merge tag 'nds32-for-linus-4.19-tag1' of... · d0c1db1d
      Linus Torvalds authored
      Merge tag 'nds32-for-linus-4.19-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux
      
      Pull nds32 updates from Greentime Hu:
       "Contained in here are the bug fixes, building error fixes and ftrace
        support for nds32"
      
      * tag 'nds32-for-linus-4.19-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux:
        nds32: linker script: GCOV kernel may refers data in __exit
        nds32: fix build error because of wrong semicolon
        nds32: Fix a kernel panic issue because of wrong frame pointer access.
        nds32: Only print one page of stack when die to prevent printing too much information.
        nds32: Add macro definition for offset of lp register on stack
        nds32: Remove the deprecated ABI implementation
        nds32/stack: Get real return address by using ftrace_graph_ret_addr
        nds32/ftrace: Support dynamic function graph tracer
        nds32/ftrace: Support dynamic function tracer
        nds32/ftrace: Add RECORD_MCOUNT support
        nds32/ftrace: Support static function graph tracer
        nds32/ftrace: Support static function tracer
        nds32: Extract the checking and getting pointer to a macro
        nds32: Clean up the coding style
        nds32: Fix get_user/put_user macro expand pointer problem
        nds32: Fix empty call trace
        nds32: add NULL entry to the end of_device_id array
        nds32: fix logic for module
      d0c1db1d
    • Steven Rostedt (VMware)'s avatar
      tracing: Add back in rcu_irq_enter/exit_irqson() for rcuidle tracepoints · 865e63b0
      Steven Rostedt (VMware) authored
      Borislav reported the following splat:
      
       =============================
       WARNING: suspicious RCU usage
       4.19.0-rc1+ #1 Not tainted
       -----------------------------
       ./include/linux/rcupdate.h:631 rcu_read_lock() used illegally while idle!
       other info that might help us debug this:
      
       RCU used illegally from idle CPU!
       rcu_scheduler_active = 2, debug_locks = 1
       RCU used illegally from extended quiescent state!
       1 lock held by swapper/0/0:
        #0: 000000004557ee0e (rcu_read_lock){....}, at: perf_event_output_forward+0x0/0x130
      
       stack backtrace:
       CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.0-rc1+ #1
       Hardware name: LENOVO 2320CTO/2320CTO, BIOS G2ET86WW (2.06 ) 11/13/2012
       Call Trace:
        dump_stack+0x85/0xcb
        perf_event_output_forward+0xf6/0x130
        __perf_event_overflow+0x52/0xe0
        perf_swevent_overflow+0x91/0xb0
        perf_tp_event+0x11a/0x350
        ? find_held_lock+0x2d/0x90
        ? __lock_acquire+0x2ce/0x1350
        ? __lock_acquire+0x2ce/0x1350
        ? retint_kernel+0x2d/0x2d
        ? find_held_lock+0x2d/0x90
        ? tick_nohz_get_sleep_length+0x83/0xb0
        ? perf_trace_cpu+0xbb/0xd0
        ? perf_trace_buf_alloc+0x5a/0xa0
        perf_trace_cpu+0xbb/0xd0
        cpuidle_enter_state+0x185/0x340
        do_idle+0x1eb/0x260
        cpu_startup_entry+0x5f/0x70
        start_kernel+0x49b/0x4a6
        secondary_startup_64+0xa4/0xb0
      
      This is due to the tracepoints moving to SRCU usage which does not require
      RCU to be "watching". But perf uses these tracepoints with RCU and expects
      it to be. Hence, we still need to add in the rcu_irq_enter/exit_irqson()
      calls for "rcuidle" tracepoints. This is a temporary fix until we have SRCU
      working in NMI context, and then perf can be converted to use that instead
      of normal RCU.
      
      Link: http://lkml.kernel.org/r/20180904162611.6a120068@gandalf.local.home
      
      
      
      Cc: x86-ml <x86@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Reported-by: default avatarBorislav Petkov <bp@alien8.de>
      Tested-by: default avatarBorislav Petkov <bp@alien8.de>
      Reviewed-by: default avatar"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
      Fixes: e6753f23
      
       ("tracepoint: Make rcuidle tracepoint callers use SRCU")
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      865e63b0
    • Greentime Hu's avatar
      nds32: linker script: GCOV kernel may refers data in __exit · 3350139c
      Greentime Hu authored
      This patch is used to fix nds32 allmodconfig/allyesconfig build error
      because GCOV kernel embeds counters in the kernel for each line
      and a part of that embed in __exit text. So we need to keep the
      EXIT_TEXT and EXIT_DATA  if CONFIG_GCOV_KERNEL=y.
      
      Link: https://lkml.org/lkml/2018/9/1/125
      
      Signed-off-by: default avatarGreentime Hu <greentime@andestech.com>
      Reviewed-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      3350139c
    • Linus Torvalds's avatar
      Merge branch 'akpm' (patches from Andrew) · 0e9b1039
      Linus Torvalds authored
      Merge misc fixes from Andrew Morton:
       "17 fixes"
      
      * emailed patches from Andrew Morton <akpm@linux-foundation.org>:
        nilfs2: convert to SPDX license tags
        drivers/dax/device.c: convert variable to vm_fault_t type
        lib/Kconfig.debug: fix three typos in help text
        checkpatch: add __ro_after_init to known $Attribute
        mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal
        uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name
        memory_hotplug: fix kernel_panic on offline page processing
        checkpatch: add optional static const to blank line declarations test
        ipc/shm: properly return EIDRM in shm_lock()
        mm/hugetlb: filter out hugetlb pages if HUGEPAGE migration is not supported.
        mm/util.c: improve kvfree() kerneldoc
        tools/vm/page-types.c: fix "defined but not used" warning
        tools/vm/slabinfo.c: fix sign-compare warning
        kmemleak: always register debugfs file
        mm: respect arch_dup_mmap() return value
        mm, oom: fix missing tlb_finish_mmu() in __oom_reap_task_mm().
        mm: memcontrol: print proper OOM header when no eligible victim left
      0e9b1039
  9. 04 Sep, 2018 11 commits