1. 14 Dec, 2015 20 commits
  2. 13 Dec, 2015 8 commits
    • Peter Zijlstra's avatar
      sched/wait: Fix the signal handling fix · dfd01f02
      Peter Zijlstra authored
      Jan Stancek reported that I wrecked things for him by fixing things for
      Vladimir :/
      
      His report was due to an UNINTERRUPTIBLE wait getting -EINTR, which
      should not be possible, however my previous patch made this possible by
      unconditionally checking signal_pending().
      
      We cannot use current->state as was done previously, because the
      instruction after the store to that variable it can be changed.  We must
      instead pass the initial state along and use that.
      
      Fixes: 68985633
      
       ("sched/wait: Fix signal handling in bit wait helpers")
      Reported-by: default avatarJan Stancek <jstancek@redhat.com>
      Reported-by: default avatarChris Mason <clm@fb.com>
      Tested-by: default avatarJan Stancek <jstancek@redhat.com>
      Tested-by: default avatarVladimir Murzin <vladimir.murzin@arm.com>
      Tested-by: default avatarChris Mason <clm@fb.com>
      Reviewed-by: default avatarPaul Turner <pjt@google.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: tglx@linutronix.de
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: hpa@zytor.com
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      dfd01f02
    • Linus Torvalds's avatar
      Merge tag 'nfs-for-4.4-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs · fc891828
      Linus Torvalds authored
      Pull NFS client bugfix from Trond Myklebust:
       "SUNRPC: Fix a NFSv4.1 callback channel regression"
      
      * tag 'nfs-for-4.4-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
        SUNRPC: Fix callback channel
      fc891828
    • Linus Torvalds's avatar
      Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · dec9cbf9
      Linus Torvalds authored
      Pull timer fixlets from Thomas Gleixner:
       "Two trivial fixes which add missing header fileas and forward
        declarations so the code will compile even when the magic include
        chains are different"
      
      * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        irqchip/gic-v3: Add missing include for barrier.h
        irqchip/gic-v3: Add missing struct device_node declaration
      dec9cbf9
    • Linus Torvalds's avatar
      Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 43afc99d
      Linus Torvalds authored
      Pull timer fix from Thomas Gleixner:
       "A single fix to unbreak a clocksource driver which has more than 32bit
        counter width"
      
      * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        clocksource: Mmio: remove artificial 32bit limitation
      43afc99d
    • Linus Torvalds's avatar
      Merge tag 'char-misc-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc · f17ef495
      Linus Torvalds authored
      Pull fpga driver fixes from Greg KH:
       "Only two small fpga driver fixes here, both have been in linux-next
        for a while, and resolve some reported issues"
      
      * tag 'char-misc-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
        fpga manager: Fix firmware resource leak on error
        fpga manager: remove label
      f17ef495
    • Linus Torvalds's avatar
      Merge tag 'staging-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging · b24f74e3
      Linus Torvalds authored
      Pull staging driver fixes from Greg KH:
       "Here are a few staging and IIO driver fixes for 4.4-rc5.
      
        All of them resolve reported problems and have been in linux-next for
        a while.  Nothing major here, just small fixes where needed"
      
      * tag 'staging-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
        staging: lustre: echo_copy.._lsm() dereferences userland pointers directly
        iio: adc: spmi-vadc: add missing of_node_put
        iio: fix some warning messages
        iio: light: apds9960: correct ->last_busy count
        iio: lidar: return -EINVAL on invalid signal
        staging: iio: dummy: complete IIO events delivery to userspace
      b24f74e3
    • Linus Torvalds's avatar
      Merge tag 'usb-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb · c474009c
      Linus Torvalds authored
      Pull USB driver fixes from Greg KH:
       "Here are a number of small USB fixes for 4.4-rc5.  All of them have
        been in linux-next.  The majority are gadget and phy issues, with a
        few new quirks and device ids added as well"
      
      * tag 'usb-4.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (32 commits)
        USB: add quirk for devices with broken LPM
        xhci: fix usb2 resume timing and races.
        usb: musb: fail with error when no DMA controller set
        usb: gadget: uvc: fix permissions of configfs attributes
        usb: musb: core: Fix pm runtime for deferred probe
        usb: phy: msm: fix a possible NULL dereference
        USB: host: ohci-at91: fix a crash in ohci_hcd_at91_overcurrent_irq
        usb: Quiet down false peer failure messages
        usb: xhci: fix config fail of FS hub behind a HS hub with MTT
        xhci: Fix memory leak in xhci_pme_acpi_rtd3_enable()
        usb: Use the USB_SS_MULT() macro to decode burst multiplier for log message
        USB: whci-hcd: add check for dma mapping error
        usb: core : hub: Fix BOS 'NULL pointer' kernel panic
        USB: quirks: Apply ALWAYS_POLL to all ELAN devices
        usb-storage: Fix scsi-sd failure "Invalid field in cdb" for USB adapter JMicron
        USB: quirks: Fix another ELAN touchscreen
        usb: dwc3: gadget: don't prestart interrupt endpoints
        USB: serial: Another Infineon flash loader USB ID
        USB: cdc_acm: Ignore Infineon Flash Loader utility
        USB: cp210x: Remove CP2110 ID from compatibility list
        ...
      c474009c
    • Linus Torvalds's avatar
      Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc · 097b285d
      Linus Torvalds authored
      Pull ARM SoC fixes from Arnd Bergmann:
       "Here are a bunch of small bug fixes for various ARM platforms, nothing
        really sticks out this week, most of either fixes bugs in code that
        was just added in 4.4, or that has been broken for many years without
        anyone noticing.
      
        at91/sama5d2:
         - fix sama5de hardware setup of sd/mmc interface
         - proper selection of pinctrl drivers.  PIO4 is necessary for sama5d2
      
        berlin:
         - fix incorrect clock input for SDIO
      
        exynos:
         - Fix potential NULL pointer dereference in Exynos PMU driver.
      
        imx:
         - Fix vf610 SAI clock configuration bug which is discovered by the
           newly added master mode support in SAI audio driver.
         - Fix buggy L2 cache latency values in vf610 device trees, which may
           cause system hang when cpu runs at a higher frequency.
      
        ixp4xx:
         - fix prototypes for readl/writel functions
      
        ls2080a:
         - use little-endian register access for GPIO and SDHCI
      
        omap:
         - Fix clock source for ARM TWD and global timers on am437x
         - Always select REGULATOR_FIXED_VOLTAGE for omap2+ instead of when
           MACH_OMAP3_PANDORA is selected
         - Fix SPI DMA handles for dm816x as only some were mapped
         - Fix up mbox cells for dm816x to make mailbox usable
      
        pxa:
         - use PWM lookup table for all ezx machines
      
        s3c24xx:
         - Remove incorrect __init annotation from s3c24xx cpufreq driver
           structures.
      
        versatile:
         - fix PCI IRQ mapping on Versatile PB"
      
      * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
        ls2080a/dts: Add little endian property for GPIO IP block
        dt-bindings: define little-endian property for QorIQ GPIO
        ARM64: dts: ls2080a: fix eSDHC endianness
        ARM: dts: vf610: use reset values for L2 cache latencies
        ARM: pxa: use PWM lookup table for all machines
        ARM: dts: berlin: add 2nd clock for BG2Q sdhci0 and sdhci1
        ARM: dts: berlin: correct BG2Q's sdhci2 2nd clock
        ARM: dts: am4372: fix clock source for arm twd and global timers
        ARM: at91: fix pinctrl driver selection
        ARM: at91/dt: add always-on to 1.8V regulator
        ARM: dts: vf610: fix clock definition for SAI2
        ARM: imx: clk-vf610: fix SAI clock tree
        ARM: ixp4xx: fix read{b,w,l} return types
        irqchip/versatile-fpga: Fix PCI IRQ mapping on Versatile PB
        ARM: OMAP2+: enable REGULATOR_FIXED_VOLTAGE
        ARM: dts: add dm816x missing spi DT dma handles
        ARM: dts: add dm816x missing #mbox-cells
        cpufreq: s3c24xx: Do not mark s3c2410_plls_add as __init
        ARM: EXYNOS: Fix potential NULL pointer access in exynos_sys_powerdown_conf
      097b285d
  3. 12 Dec, 2015 12 commits
    • Linus Torvalds's avatar
      Merge tag 'powerpc-4.4-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux · 79dbddaf
      Linus Torvalds authored
      Pull powerpc fixes from Michael Ellerman:
       - opal-irqchip: Fix double endian conversion from Alistair Popple
       - cxl: Set endianess of kernel contexts from Frederic Barrat
       - sbc8641: drop bogus PHY IRQ entries from DTS file from Paul Gortmaker
       - Revert "powerpc/eeh: Don't unfreeze PHB PE after reset" from Andrew
         Donnellan
      
      * tag 'powerpc-4.4-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
        Revert "powerpc/eeh: Don't unfreeze PHB PE after reset"
        powerpc/sbc8641: drop bogus PHY IRQ entries from DTS file
        cxl: Set endianess of kernel contexts
        powerpc/opal-irqchip: Fix double endian conversion
      79dbddaf
    • Linus Torvalds's avatar
      Merge branch 'akpm' (patches from Andrew) · 800f1ac4
      Linus Torvalds authored
      Merge misc fixes from Andrew Morton:
       "17 fixes"
      
      * emailed patches from Andrew Morton <akpm@linux-foundation.org>:
        MIPS: fix DMA contiguous allocation
        sh64: fix __NR_fgetxattr
        ocfs2: fix SGID not inherited issue
        mm/oom_kill.c: avoid attempting to kill init sharing same memory
        drivers/base/memory.c: prohibit offlining of memory blocks with missing sections
        tmpfs: fix shmem_evict_inode() warnings on i_blocks
        mm/hugetlb.c: fix resv map memory leak for placeholder entries
        mm: hugetlb: call huge_pte_alloc() only if ptep is null
        kernel: remove stop_machine() Kconfig dependency
        mm: kmemleak: mark kmemleak_init prototype as __init
        mm: fix kerneldoc on mem_cgroup_replace_page
        osd fs: __r4w_get_page rely on PageUptodate for uptodate
        MAINTAINERS: make Vladimir co-maintainer of the memory controller
        mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress
        mm: fix swapped Movable and Reclaimable in /proc/pagetypeinfo
        memcg: fix memory.high target
        mm: hugetlb: fix hugepage memory leak caused by wrong reserve count
      800f1ac4
    • Linus Torvalds's avatar
      Merge branch 'parisc-4.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux · a971526e
      Linus Torvalds authored
      Pull parisc fixes from Helge Deller:
       "Fix the boot crash on Mako machines with Huge Pages, prevent a panic
        with SATA controllers (and others) by correctly calculating the IOMMU
        space, hook up the mlock2 syscall and drop unneeded code in the parisc
        pci code"
      
      * 'parisc-4.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
        parisc: Disable huge pages on Mako machines
        parisc: Wire up mlock2 syscall
        parisc: Remove unused pcibios_init_bus()
        parisc iommu: fix panic due to trying to allocate too large region
      a971526e
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.dk/linux-block · 78075631
      Linus Torvalds authored
      Pull block layer fixes from Jens Axboe:
       "A set of fixes for the current series.  This contains:
      
         - A bunch of fixes for lightnvm, should be the last round for this
           series.  From Matias and Wenwei.
      
         - A writeback detach inode fix from Ilya, also marked for stable.
      
         - A block (though it says SCSI) fix for an OOPS in SCSI runtime power
           management.
      
         - Module init error path fixes for null_blk from Minfei"
      
      * 'for-linus' of git://git.kernel.dk/linux-block:
        null_blk: Fix error path in module initialization
        lightnvm: do not compile in debugging by default
        lightnvm: prevent gennvm module unload on use
        lightnvm: fix media mgr registration
        lightnvm: replace req queue with nvmdev for lld
        lightnvm: comments on constants
        lightnvm: check mm before use
        lightnvm: refactor spin_unlock in gennvm_get_blk
        lightnvm: put blks when luns configure failed
        lightnvm: use flags in rrpc_get_blk
        block: detach bdev inode from its wb in __blkdev_put()
        SCSI: Fix NULL pointer dereference in runtime PM
      78075631
    • Linus Torvalds's avatar
      Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux · 6539756e
      Linus Torvalds authored
      Pull arm64 fixes from Catalin Marinas:
      
       - Update the linker script to use L1_CACHE_BYTES instead of hard-coded
         64.  We recently changed L1_CACHE_BYTES to 128
      
       - Improve race condition reporting on set_pte_at() and change the BUG
         to WARN_ONCE.  With hardware update of the accessed/dirty state, we
         need to ensure that set_pte_at() does not inadvertently override
         hardware updated state.  The patch also makes the checks ignore
         !pte_valid() new entries
      
      * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
        arm64: Improve error reporting on set_pte_at() checks
        arm64: update linker script to increased L1_CACHE_BYTES value
      6539756e
    • Qais Yousef's avatar
      MIPS: fix DMA contiguous allocation · 9530d0fe
      Qais Yousef authored
      Recent changes to how GFP_ATOMIC is defined seems to have broken the
      condition to use mips_alloc_from_contiguous() in
      mips_dma_alloc_coherent().
      
      I couldn't bottom out the exact change but I think it's this commit
      d0164adc
      
       ("mm, page_alloc: distinguish between being unable to
      sleep, unwilling to sleep and avoiding waking kswapd").
      
      GFP_ATOMIC has multiple bits set and the check for !(gfp & GFP_ATOMIC)
      isn't enough.
      
      The reason behind this condition is to check whether we can potentially
      do a sleeping memory allocation.  Use gfpflags_allow_blocking() instead
      which should be more robust.
      Signed-off-by: default avatarQais Yousef <qais.yousef@imgtec.com>
      Acked-by: default avatarMel Gorman <mgorman@techsingularity.net>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9530d0fe
    • Dmitry V. Levin's avatar
      sh64: fix __NR_fgetxattr · 2d33fa10
      Dmitry V. Levin authored
      
      
      According to arch/sh/kernel/syscalls_64.S and common sense, __NR_fgetxattr
      has to be defined to 259, but it doesn't.  Instead, it's defined to 269,
      which is of course used by another syscall, __NR_sched_setaffinity in this
      case.
      
      This bug was found by strace test suite.
      Signed-off-by: default avatarDmitry V. Levin <ldv@altlinux.org>
      Acked-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      2d33fa10
    • Junxiao Bi's avatar
      ocfs2: fix SGID not inherited issue · 854ee2e9
      Junxiao Bi authored
      Commit 8f1eb487 ("ocfs2: fix umask ignored issue") introduced an
      issue, SGID of sub dir was not inherited from its parents dir.  It is
      because SGID is set into "inode->i_mode" in ocfs2_get_init_inode(), but
      is overwritten by "mode" which don't have SGID set later.
      
      Fixes: 8f1eb487
      
       ("ocfs2: fix umask ignored issue")
      Signed-off-by: default avatarJunxiao Bi <junxiao.bi@oracle.com>
      Cc: Mark Fasheh <mfasheh@suse.de>
      Cc: Joel Becker <jlbec@evilplan.org>
      Acked-by: default avatarSrinivas Eeda <srinivas.eeda@oracle.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      854ee2e9
    • Chen Jie's avatar
      mm/oom_kill.c: avoid attempting to kill init sharing same memory · a2b829d9
      Chen Jie authored
      
      
      It's possible that an oom killed victim shares an ->mm with the init
      process and thus oom_kill_process() would end up trying to kill init as
      well.
      
      This has been shown in practice:
      
      	Out of memory: Kill process 9134 (init) score 3 or sacrifice child
      	Killed process 9134 (init) total-vm:1868kB, anon-rss:84kB, file-rss:572kB
      	Kill process 1 (init) sharing same memory
      	...
      	Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009
      
      And this will result in a kernel panic.
      
      If a process is forked by init and selected for oom kill while still
      sharing init_mm, then it's likely this system is in a recoverable state.
      However, it's better not to try to kill init and allow the machine to
      panic due to unkillable processes.
      
      [rientjes@google.com: rewrote changelog]
      [akpm@linux-foundation.org: fix inverted test, per Ben]
      Signed-off-by: default avatarChen Jie <chenjie6@huawei.com>
      Signed-off-by: default avatarDavid Rientjes <rientjes@google.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Acked-by: default avatarHillf Danton <hillf.zj@alibaba-inc.com>
      Cc: Ben Hutchings <ben@decadent.org.uk>
      Cc: Li Zefan <lizefan@huawei.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a2b829d9
    • Seth Jennings's avatar
      drivers/base/memory.c: prohibit offlining of memory blocks with missing sections · 26bbe7ef
      Seth Jennings authored
      Commit bdee237c ("x86: mm: Use 2GB memory block size on large-memory
      x86-64 systems") and 982792c7 ("x86, mm: probe memory block size for
      generic x86 64bit") introduced large block sizes for x86.  This made it
      possible to have multiple sections per memory block where previously,
      there was a only every one section per block.
      
      Since blocks consist of contiguous ranges of section, there can be holes
      in the blocks where sections are not present.  If one attempts to
      offline such a block, a crash occurs since the code is not designed to
      deal with this.
      
      This patch is a quick fix to gaurd against the crash by not allowing
      blocks with non-present sections to be offlined.
      
      Addresses https://bugzilla.kernel.org/show_bug.cgi?id=107781
      
      Signed-off-by: default avatarSeth Jennings <sjennings@variantweb.net>
      Reported-by: default avatarAndrew Banman <abanman@sgi.com>
      Cc: Daniel J Blueman <daniel@numascale.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: Greg KH <greg@kroah.com>
      Cc: Russ Anderson <rja@sgi.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      26bbe7ef
    • Hugh Dickins's avatar
      tmpfs: fix shmem_evict_inode() warnings on i_blocks · 267a4c76
      Hugh Dickins authored
      Dmitry Vyukov provides a little program, autogenerated by syzkaller,
      which races a fault on a mapping of a sparse memfd object, against
      truncation of that object below the fault address: run repeatedly for a
      few minutes, it reliably generates shmem_evict_inode()'s
      WARN_ON(inode->i_blocks).
      
      (But there's nothing specific to memfd here, nor to the fstat which it
      happened to use to generate the fault: though that looked suspicious,
      since a shmem_recalc_inode() had been added there recently.  The same
      problem can be reproduced with open+unlink in place of memfd_create, and
      with fstatfs in place of fstat.)
      
      v3.7 commit 0f3c42f5
      
       ("tmpfs: change final i_blocks BUG to WARNING")
      explains one cause of such a warning (a race with shmem_writepage to
      swap), and possible solutions; but we never took it further, and this
      syzkaller incident turns out to have a different cause.
      
      shmem_getpage_gfp()'s error recovery, when a freshly allocated page is
      then found to be beyond eof, looks plausible - decrementing the alloced
      count that was just before incremented - but in fact can go wrong, if a
      racing thread (the truncator, for example) gets its shmem_recalc_inode()
      in just after our delete_from_page_cache().  delete_from_page_cache()
      decrements nrpages, that shmem_recalc_inode() will balance the books by
      decrementing alloced itself, then our decrement of alloced take it one
      too low: leading to the WARNING when the object is finally evicted.
      
      Once the new page has been exposed in the page cache,
      shmem_getpage_gfp() must leave it to shmem_recalc_inode() itself to get
      the accounting right in all cases (and not fall through from "trunc:" to
      "decused:").  Adjust that error recovery block; and the reinitialization
      of info and sbinfo can be removed too.
      
      While we're here, fix shmem_writepage() to avoid the original issue: it
      will be safe against a racing shmem_recalc_inode(), if it merely
      increments swapped before the shmem_delete_from_page_cache() which
      decrements nrpages (but it must then do its own shmem_recalc_inode()
      before that, while still in balance, instead of after).  (Aside: why do
      we shmem_recalc_inode() here in the swap path? Because its raison d'etre
      is to cope with clean sparse shmem pages being reclaimed behind our
      back: so here when swapping is a good place to look for that case.) But
      I've not now managed to reproduce this bug, even without the patch.
      
      I don't see why I didn't do that earlier: perhaps inhibited by the
      preference to eliminate shmem_recalc_inode() altogether.  Driven by this
      incident, I do now have a patch to do so at last; but still want to sit
      on it for a bit, there's a couple of questions yet to be resolved.
      Signed-off-by: default avatarHugh Dickins <hughd@google.com>
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      267a4c76
    • Mike Kravetz's avatar
      mm/hugetlb.c: fix resv map memory leak for placeholder entries · dbe409e4
      Mike Kravetz authored
      Dmitry Vyukov reported the following memory leak
      
      unreferenced object 0xffff88002eaafd88 (size 32):
        comm "a.out", pid 5063, jiffies 4295774645 (age 15.810s)
        hex dump (first 32 bytes):
          28 e9 4e 63 00 88 ff ff 28 e9 4e 63 00 88 ff ff  (.Nc....(.Nc....
          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
        backtrace:
           kmalloc include/linux/slab.h:458
           region_chg+0x2d4/0x6b0 mm/hugetlb.c:398
           __vma_reservation_common+0x2c3/0x390 mm/hugetlb.c:1791
           vma_needs_reservation mm/hugetlb.c:1813
           alloc_huge_page+0x19e/0xc70 mm/hugetlb.c:1845
           hugetlb_no_page mm/hugetlb.c:3543
           hugetlb_fault+0x7a1/0x1250 mm/hugetlb.c:3717
           follow_hugetlb_page+0x339/0xc70 mm/hugetlb.c:3880
           __get_user_pages+0x542/0xf30 mm/gup.c:497
           populate_vma_page_range+0xde/0x110 mm/gup.c:919
           __mm_populate+0x1c7/0x310 mm/gup.c:969
           do_mlock+0x291/0x360 mm/mlock.c:637
           SYSC_mlock2 mm/mlock.c:658
           SyS_mlock2+0x4b/0x70 mm/mlock.c:648
      
      Dmitry identified a potential memory leak in the routine region_chg,
      where a region descriptor is not free'ed on an error path.
      
      However, the root cause for the above memory leak resides in region_del.
      In this specific case, a "placeholder" entry is created in region_chg.
      The associated page allocation fails, and the placeholder entry is left
      in the reserve map.  This is "by design" as the entry should be deleted
      when the map is released.  The bug is in the region_del routine which is
      used to delete entries within a specific range (and when the map is
      released).  region_del did not handle the case where a placeholder entry
      exactly matched the start of the range range to be deleted.  In this
      case, the entry would not be deleted and leaked.  The fix is to take
      these special placeholder entries into account in region_del.
      
      The region_chg error path leak is also fixed.
      
      Fixes: feba16e2
      
       ("mm/hugetlb: add region_del() to delete a specific range of entries")
      Signed-off-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Acked-by: default avatarHillf Danton <hillf.zj@alibaba-inc.com>
      Cc: <stable@vger.kernel.org>	[4.3+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      dbe409e4