1. 09 Jun, 2017 1 commit
    • Dan Williams's avatar
      device-dax: fix 'dax' device filesystem inode destruction crash · b9d39d17
      Dan Williams authored
      The inode destruction path for the 'dax' device filesystem incorrectly
      assumes that the inode was initialized through 'alloc_dax()'. However,
      if someone attempts to directly mount the dax filesystem with 'mount -t
      dax dax mnt' that will bypass 'alloc_dax()' and the following failure
      signatures may occur as a result:
      
       kill_dax() must be called before final iput()
       WARNING: CPU: 2 PID: 1188 at drivers/dax/super.c:243 dax_destroy_inode+0x48/0x50
       RIP: 0010:dax_destroy_inode+0x48/0x50
       Call Trace:
        destroy_inode+0x3b/0x60
        evict+0x139/0x1c0
        iput+0x1f9/0x2d0
        dentry_unlink_inode+0xc3/0x160
        __dentry_kill+0xcf/0x180
        ? dput+0x37/0x3b0
        dput+0x3a3/0x3b0
        do_one_tree+0x36/0x40
        shrink_dcache_for_umount+0x2d/0x90
        generic_shutdown_super+0x1f/0x120
        kill_anon_super+0x12/0x20
        deactivate_locked_super+0x43/0x70
        deactivate_super+0x4e/0x60
      
       general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
       RIP: 0010:kfree+0x6d/0x290
       Call Trace:
        <IRQ>
        dax_i_callback+0x22/0x60
        ? dax_destroy_inode+0x50/0x50
        rcu_process_callbacks+0x298/0x740
      
       ida_remove called for id=0 which is not allocated.
       WARNING: CPU: 0 PID: 0 at lib/idr.c:383 ida_remove+0x110/0x120
       [..]
       Call Trace:
        <IRQ>
        ida_simple_remove+0x2b/0x50
        ? dax_destroy_inode+0x50/0x50
        dax_i_callback+0x3c/0x60
        rcu_process_callbacks+0x298/0x740
      
      Add missing initialization of the 'struct dax_device' and inode so that
      the destruction path does not kfree() or ida_simple_remove()
      uninitialized data.
      
      Fixes: 7b6be844
      
       ("dax: refactor dax-fs into a generic provider of 'struct dax_device' instances")
      Reported-by: default avatarSasha Levin <alexander.levin@verizon.com>
      Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
      b9d39d17
  2. 04 Jun, 2017 9 commits
    • Linus Torvalds's avatar
      Linux 4.12-rc4 · 3c2993b8
      Linus Torvalds authored
      3c2993b8
    • Richard Narron's avatar
      fs/ufs: Set UFS default maximum bytes per file · 239e250e
      Richard Narron authored
      This fixes a problem with reading files larger than 2GB from a UFS-2
      file system:
      
          https://bugzilla.kernel.org/show_bug.cgi?id=195721
      
      The incorrect UFS s_maxsize limit became a problem as of commit
      c2a9737f
      
       ("vfs,mm: fix a dead loop in truncate_inode_pages_range()")
      which started using s_maxbytes to avoid a page index overflow in
      do_generic_file_read().
      
      That caused files to be truncated on UFS-2 file systems because the
      default maximum file size is 2GB (MAX_NON_LFS) and UFS didn't update it.
      
      Here I simply increase the default to a common value used by other file
      systems.
      Signed-off-by: default avatarRichard Narron <comet.berkeley@gmail.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Will B <will.brokenbourgh2877@gmail.com>
      Cc: Theodore Ts'o <tytso@mit.edu>
      Cc: <stable@vger.kernel.org> # v4.9 and backports of c2a9737f
      
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      239e250e
    • Linus Torvalds's avatar
      Merge tag 'nfs-for-4.12-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs · 125f42b0
      Linus Torvalds authored
      Pull NFS client bugfixes from Trond Myklebust:
       "Bugfixes include:
      
         - Fix a typo in commit e0926934 ("NFS append COMMIT after
           synchronous COPY") that breaks copy offload
      
         - Fix the connect error propagation in xs_tcp_setup_socket()
      
         - Fix a lock leak in nfs40_walk_client_list
      
         - Verify that pNFS requests lie within the offset range of the layout
           segment"
      
      * tag 'nfs-for-4.12-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
        nfs: Mark unnecessarily extern functions as static
        SUNRPC: ensure correct error is reported by xs_tcp_setup_socket()
        NFSv4.0: Fix a lock leak in nfs40_walk_client_list
        pnfs: Fix the check for requests in range of layout segment
        xprtrdma: Delete an error message for a failed memory allocation in xprt_rdma_bc_setup()
        pNFS/flexfiles: missing error code in ff_layout_alloc_lseg()
        NFS fix COMMIT after COPY
      125f42b0
    • Linus Torvalds's avatar
      Merge tag 'tty-4.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty · 3c06e6cb
      Linus Torvalds authored
      Pull tty fix from Greg KH:
       "Here is a single tty core fix for 4.12-rc4. It reverts a patch that a
        lot of people reported as causing lockdep and other warnings.
      
        Right after I reverted this in my tree, it seems like another
        "correct" fix might have shown up, but it's too late in the release
        cycle to be messing with tty core locking, so let's just revert this
        for now to go back how things always have been and try it again for
        4.13.
      
        This has not been in linux-next as I only reverted it a few hours ago"
      
      * tag 'tty-4.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
        Revert "tty: fix port buffer locking"
      3c06e6cb
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input · e00811b4
      Linus Torvalds authored
      Pull input subsystem fixes from Dmitry Torokhov:
      
       - a couple of regression fixes in synaptics and axp20x-pek drivers
      
       - try to ease transition from PS/2 to RMI for Synaptics touchpad users
         by ensuring we do not try to activate RMI mode when RMI SMBus support
         is not enabled, and nag users a bit to enable it
      
       - plus a couple of other changes that seemed worthwhile for this
         release
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
        Input: axp20x-pek - switch to acpi_dev_present and check for ACPI0011 too
        Input: axp20x-pek - only check for "INTCFD9" ACPI device on Cherry Trail
        Input: tm2-touchkey - use LEN_ON as boolean value instead of LED_FULL
        Input: synaptics - tell users to report when they should be using rmi-smbus
        Input: synaptics - warn the users when there is a better mode
        Input: synaptics - keep PS/2 around when RMI4_SMB is not enabled
        Input: synaptics - clear device info before filling in
        Input: silead - disable interrupt during suspend
      e00811b4
    • Linus Torvalds's avatar
      Merge tag 'rtc-4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux · 9f03b2c7
      Linus Torvalds authored
      Pull RTC fixlet from Alexandre Belloni:
       "A single patch, not really a fix but I don't think there is any reason
        to delay it.
      
        Change the mailing list address"
      
      * tag 'rtc-4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
        MAINTAINERS: update RTC mailing list
      9f03b2c7
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · 1f915b7f
      Linus Torvalds authored
      Pull SCSI fixes from James Bottomley:
       "This is nine fixes, seven of which are for the qedi driver (new as of
        4.10) the other two are a use after free in the cxgbi drivers and a
        potential NULL dereference in the rdac device handler"
      
      * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        scsi: libcxgbi: fix skb use after free
        scsi: qedi: Fix endpoint NULL panic during recovery.
        scsi: qedi: set max_fin_rt default value
        scsi: qedi: Set firmware tcp msl timer value.
        scsi: qedi: Fix endpoint NULL panic in qedi_set_path.
        scsi: qedi: Set dma_boundary to 0xfff.
        scsi: qedi: Correctly set firmware max supported BDs.
        scsi: qedi: Fix bad pte call trace when iscsiuio is stopped.
        scsi: scsi_dh_rdac: Use ctlr directly in rdac_failover_get()
      1f915b7f
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma · 55cbdaf6
      Linus Torvalds authored
      Pull rdma fixes from Doug Ledford:
       "For the most part this is just a minor -rc cycle for the rdma
        subsystem. Even given that this is all of the -rc patches since the
        merge window closed, it's still only about 25 patches:
      
         - Multiple i40iw, nes, iw_cxgb4, hfi1, qib, mlx4, mlx5 fixes
      
         - A few upper layer protocol fixes (IPoIB, iSER, SRP)
      
         - A modest number of core fixes"
      
      * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (26 commits)
        RDMA/SA: Fix kernel panic in CMA request handler flow
        RDMA/umem: Fix missing mmap_sem in get umem ODP call
        RDMA/core: not to set page dirty bit if it's already set.
        RDMA/uverbs: Declare local function static and add brackets to sizeof
        RDMA/netlink: Reduce exposure of RDMA netlink functions
        RDMA/srp: Fix NULL deref at srp_destroy_qp()
        RDMA/IPoIB: Limit the ipoib_dev_uninit_default scope
        RDMA/IPoIB: Replace netdev_priv with ipoib_priv for ipoib_get_link_ksettings
        RDMA/qedr: add null check before pointer dereference
        RDMA/mlx5: set UMR wqe fence according to HCA cap
        net/mlx5: Define interface bits for fencing UMR wqe
        RDMA/mlx4: Fix MAD tunneling when SRIOV is enabled
        RDMA/qib,hfi1: Fix MR reference count leak on write with immediate
        RDMA/hfi1: Defer setting VL15 credits to link-up interrupt
        RDMA/hfi1: change PCI bar addr assignments to Linux API functions
        RDMA/hfi1: fix array termination by appending NULL to attr array
        RDMA/iw_cxgb4: fix the calculation of ipv6 header size
        RDMA/iw_cxgb4: calculate t4_eq_status_entries properly
        RDMA/iw_cxgb4: Avoid touch after free error in ARP failure handlers
        RDMA/nes: ACK MPA Reply frame
        ...
      55cbdaf6
    • Greg Kroah-Hartman's avatar
      Revert "tty: fix port buffer locking" · fc098af1
      Greg Kroah-Hartman authored
      This reverts commit 925bb1ce
      
      .
      
      It causes lots of warnings and problems so for now, let's just revert
      it.
      
      Reported-by: <valdis.kletnieks@vt.edu>
      Reported-by: default avatarRussell King <linux@armlinux.org.uk>
      Reported-by: default avatarSergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
      Reported-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Reported-by: default avatarJiri Slaby <jslaby@suse.cz>
      Reported-by: default avatarAndrey Konovalov <andreyknvl@google.com>
      Acked-by: default avatarVegard Nossum <vegard.nossum@oracle.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      fc098af1
  3. 03 Jun, 2017 8 commits
  4. 02 Jun, 2017 22 commits
    • Linus Torvalds's avatar
      Merge tag 'acpi-4.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm · 104c08ba
      Linus Torvalds authored
      Pull ACPI fixes from Rafael Wysocki:
       "These revert one more problematic commit related to the ACPI-based
        handling of laptop lids and make some unuseful error messages coming
        from ACPICA go away.
      
        Specifics:
      
         - Revert one more commit related to the ACPI-based handling of laptop
           lids that changed the default behavior on laptops that booted with
           closed lids and introduced a regression there (Benjamin Tissoires).
      
         - Add a missing acpi_put_table() to the code implementing the
           /sys/firmware/acpi/tables interface to prevent a counter in the
           ACPICA core from overflowing (Dan Williams).
      
         - Drop error messages printed by ACPICA on acpi_get_table() reference
           counting mismatches as they need not indicate real errors at this
           point (Lv Zheng)"
      
      * tag 'acpi-4.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
        ACPICA: Tables: Fix regression introduced by a too early mechanism enabling
        Revert "ACPI / button: Change default behavior to lid_init_state=open"
        ACPI / sysfs: fix acpi_get_table() leak / acpi-sysfs denial of service
      104c08ba
    • Linus Torvalds's avatar
      Merge tag 'pm-4.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm · 89af529a
      Linus Torvalds authored
      Pull power management fixes from Rafael Wysocki:
       "These fix two bugs in error code paths in the cpufreq core and in the
        kirkwood-cpufreq driver.
      
        Specifics:
      
         - Make cpufreq_register_driver() return an error if the ->init()
           calls fail for all CPUs to prevent non-functional drivers from
           hanging around for no reason (David Arcari).
      
         - Make kirkwood-cpufreq check the return value of
           clk_prepare_enable() (which may fail) as appropriate (Arvind
           Yadav)"
      
      * tag 'pm-4.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
        cpufreq: kirkwood-cpufreq:- Handle return value of clk_prepare_enable()
        cpufreq: cpufreq_register_driver() should return -ENODEV if init fails
      89af529a
    • Linus Torvalds's avatar
      Merge tag 'random_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random · 5a4829b5
      Linus Torvalds authored
      Pull /dev/random bug fix from Ted Ts'o:
       "Fix a race on architectures with prioritized interrupts (such as m68k)
        which can causes crashes in drivers/char/random.c:get_reg()"
      
      * tag 'random_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
        fix race in drivers/char/random.c:get_reg()
      5a4829b5
    • Linus Torvalds's avatar
      Merge branch 'akpm' (patches from Andrew) · f2197649
      Linus Torvalds authored
      Merge misc fixes from Andrew Morton:
       "15 fixes"
      
      * emailed patches from Andrew Morton <akpm@linux-foundation.org>:
        scripts/gdb: make lx-dmesg command work (reliably)
        mm: consider memblock reservations for deferred memory initialization sizing
        mm/hugetlb: report -EHWPOISON not -EFAULT when FOLL_HWPOISON is specified
        mlock: fix mlock count can not decrease in race condition
        mm/migrate: fix refcount handling when !hugepage_migration_supported()
        dax: fix race between colliding PMD & PTE entries
        mm: avoid spurious 'bad pmd' warning messages
        mm/page_alloc.c: make sure OOM victim can try allocations with no watermarks once
        pcmcia: remove left-over %Z format
        slub/memcg: cure the brainless abuse of sysfs attributes
        initramfs: fix disabling of initramfs (and its compression)
        mm: clarify why we want kmalloc before falling backto vmallock
        frv: declare jiffies to be located in the .data section
        include/linux/gfp.h: fix ___GFP_NOLOCKDEP value
        ksm: prevent crash after write_protect_page fails
      f2197649
    • André Draszik's avatar
      scripts/gdb: make lx-dmesg command work (reliably) · d6c97087
      André Draszik authored
      lx-dmesg needs access to the log_buf symbol from printk.c.
      Unfortunately, the symbol log_buf also exists in BPF's verifier.c and
      hence gdb can pick one or the other.  If it happens to pick BPF's
      log_buf, lx-dmesg doesn't work:
      
        (gdb) lx-dmesg
        Python Exception <class 'gdb.MemoryError'> Cannot access memory at address 0x0:
        Error occurred in Python command: Cannot access memory at address 0x0
        (gdb) p log_buf
        $15 = 0x0
      
      Luckily, GDB has a way to deal with this, see
        https://sourceware.org/gdb/onlinedocs/gdb/Symbols.html
      
        (gdb) info variables ^log_buf$
        All variables matching regular expression "^log_buf$":
      
        File <linux.git>/kernel/bpf/verifier.c:
        static char *log_buf;
      
        File <linux.git>/kernel/printk/printk.c:
        static char *log_buf;
        (gdb) p 'verifier.c'::log_buf
        $1 = 0x0
        (gdb) p 'printk.c'::log_buf
        $2 = 0x811a6aa0 <__log_buf> ""
        (gdb) p &log_buf
        $3 = (char **) 0x8120fe40 <log_buf>
        (gdb) p &'verifier.c'::log_buf
        $4 = (char **) 0x8120fe40 <log_buf>
        (gdb) p &'printk.c'::log_buf
        $5 = (char **) 0x8048b7d0 <log_buf>
      
      By being explicit about the location of the symbol, we can make lx-dmesg
      work again.  While at it, do the same for the other symbols we need from
      printk.c
      
      Link: http://lkml.kernel.org/r/20170526112222.3414-1-git@andred.net
      
      Signed-off-by: default avatarAndré Draszik <git@andred.net>
      Tested-by: default avatarKieran Bingham <kieran@bingham.xyz>
      Acked-by: default avatarJan Kiszka <jan.kiszka@siemens.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d6c97087
    • Michal Hocko's avatar
      mm: consider memblock reservations for deferred memory initialization sizing · 864b9a39
      Michal Hocko authored
      We have seen an early OOM killer invocation on ppc64 systems with
      crashkernel=4096M:
      
      	kthreadd invoked oom-killer: gfp_mask=0x16040c0(GFP_KERNEL|__GFP_COMP|__GFP_NOTRACK), nodemask=7, order=0, oom_score_adj=0
      	kthreadd cpuset=/ mems_allowed=7
      	CPU: 0 PID: 2 Comm: kthreadd Not tainted 4.4.68-1.gd7fe927-default #1
      	Call Trace:
      	  dump_stack+0xb0/0xf0 (unreliable)
      	  dump_header+0xb0/0x258
      	  out_of_memory+0x5f0/0x640
      	  __alloc_pages_nodemask+0xa8c/0xc80
      	  kmem_getpages+0x84/0x1a0
      	  fallback_alloc+0x2a4/0x320
      	  kmem_cache_alloc_node+0xc0/0x2e0
      	  copy_process.isra.25+0x260/0x1b30
      	  _do_fork+0x94/0x470
      	  kernel_thread+0x48/0x60
      	  kthreadd+0x264/0x330
      	  ret_from_kernel_thread+0x5c/0xa4
      
      	Mem-Info:
      	active_anon:0 inactive_anon:0 isolated_anon:0
      	 active_file:0 inactive_file:0 isolated_file:0
      	 unevictable:0 dirty:0 writeback:0 unstable:0
      	 slab_reclaimable:5 slab_unreclaimable:73
      	 mapped:0 shmem:0 pagetables:0 bounce:0
      	 free:0 free_pcp:0 free_cma:0
      	Node 7 DMA free:0kB min:0kB low:0kB high:0kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:52428800kB managed:110016kB mlocked:0kB dirty:0kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:320kB slab_unreclaimable:4672kB kernel_stack:1152kB pagetables:0kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes
      	lowmem_reserve[]: 0 0 0 0
      	Node 7 DMA: 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB 0*8192kB 0*16384kB = 0kB
      	0 total pagecache pages
      	0 pages in swap cache
      	Swap cache stats: add 0, delete 0, find 0/0
      	Free swap  = 0kB
      	Total swap = 0kB
      	819200 pages RAM
      	0 pages HighMem/MovableOnly
      	817481 pages reserved
      	0 pages cma reserved
      	0 pages hwpoisoned
      
      the reason is that the managed memory is too low (only 110MB) while the
      rest of the the 50GB is still waiting for the deferred intialization to
      be done.  update_defer_init estimates the initial memoty to initialize
      to 2GB at least but it doesn't consider any memory allocated in that
      range.  In this particular case we've had
      
      	Reserving 4096MB of memory at 128MB for crashkernel (System RAM: 51200MB)
      
      so the low 2GB is mostly depleted.
      
      Fix this by considering memblock allocations in the initial static
      initialization estimation.  Move the max_initialise to
      reset_deferred_meminit and implement a simple memblock_reserved_memory
      helper which iterates all reserved blocks and sums the size of all that
      start below the given address.  The cumulative size is than added on top
      of the initial estimation.  This is still not ideal because
      reset_deferred_meminit doesn't consider holes and so reservation might
      be above the initial estimation whihch we ignore but let's make the
      logic simpler until we really need to handle more complicated cases.
      
      Fixes: 3a80a7fa ("mm: meminit: initialise a subset of struct pages if CONFIG_DEFERRED_STRUCT_PAGE_INIT is set")
      Link: http://lkml.kernel.org/r/20170531104010.GI27783@dhcp22.suse.cz
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Acked-by: default avatarMel Gorman <mgorman@suse.de>
      Tested-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: <stable@vger.kernel.org>	[4.2+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      864b9a39
    • James Morse's avatar
      mm/hugetlb: report -EHWPOISON not -EFAULT when FOLL_HWPOISON is specified · 9a291a7c
      James Morse authored
      KVM uses get_user_pages() to resolve its stage2 faults.  KVM sets the
      FOLL_HWPOISON flag causing faultin_page() to return -EHWPOISON when it
      finds a VM_FAULT_HWPOISON.  KVM handles these hwpoison pages as a
      special case.  (check_user_page_hwpoison())
      
      When huge pages are involved, this doesn't work so well.
      get_user_pages() calls follow_hugetlb_page(), which stops early if it
      receives VM_FAULT_HWPOISON from hugetlb_fault(), eventually returning
      -EFAULT to the caller.  The step to map this to -EHWPOISON based on the
      FOLL_ flags is missing.  The hwpoison special case is skipped, and
      -EFAULT is returned to user-space, causing Qemu or kvmtool to exit.
      
      Instead, move this VM_FAULT_ to errno mapping code into a header file
      and use it from faultin_page() and follow_hugetlb_page().
      
      With this, KVM works as expected.
      
      This isn't a problem for arm64 today as we haven't enabled
      MEMORY_FAILURE, but I can't see any reason this doesn't happen on x86
      too, so I think this should be a fix.  This doesn't apply earlier than
      stable's v4.11.1 due to all sorts of cleanup.
      
      [james.morse@arm.com: add vm_fault_to_errno() call to faultin_page()]
      suggested.
        Link: http://lkml.kernel.org/r/20170525171035.16359-1-james.morse@arm.com
      [akpm@linux-foundation.org: coding-style fixes]
      Link: http://lkml.kernel.org/r/20170524160900.28786-1-james.morse@arm.com
      
      Signed-off-by: default avatarJames Morse <james.morse@arm.com>
      Acked-by: default avatarPunit Agrawal <punit.agrawal@arm.com>
      Acked-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: <stable@vger.kernel.org>	[4.11.1+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9a291a7c
    • Yisheng Xie's avatar
      mlock: fix mlock count can not decrease in race condition · 70feee0e
      Yisheng Xie authored
      Kefeng reported that when running the follow test, the mlock count in
      meminfo will increase permanently:
      
       [1] testcase
       linux:~ # cat test_mlockal
       grep Mlocked /proc/meminfo
        for j in `seq 0 10`
        do
       	for i in `seq 4 15`
       	do
       		./p_mlockall >> log &
       	done
       	sleep 0.2
       done
       # wait some time to let mlock counter decrease and 5s may not enough
       sleep 5
       grep Mlocked /proc/meminfo
      
       linux:~ # cat p_mlockall.c
       #include <sys/mman.h>
       #include <stdlib.h>
       #include <stdio.h>
      
       #define SPACE_LEN	4096
      
       int main(int argc, char ** argv)
       {
      	 	int ret;
      	 	void *adr = malloc(SPACE_LEN);
      	 	if (!adr)
      	 		return -1;
      
      	 	ret = mlockall(MCL_CURRENT | MCL_FUTURE);
      	 	printf("mlcokall ret = %d\n", ret);
      
      	 	ret = munlockall();
      	 	printf("munlcokall ret = %d\n", ret);
      
      	 	free(adr);
      	 	return 0;
      	 }
      
      In __munlock_pagevec() we should decrement NR_MLOCK for each page where
      we clear the PageMlocked flag.  Commit 1ebb7cc6 ("mm: munlock: batch
      NR_MLOCK zone state updates") has introduced a bug where we don't
      decrement NR_MLOCK for pages where we clear the flag, but fail to
      isolate them from the lru list (e.g.  when the pages are on some other
      cpu's percpu pagevec).  Since PageMlocked stays cleared, the NR_MLOCK
      accounting gets permanently disrupted by this.
      
      Fix it by counting the number of page whose PageMlock flag is cleared.
      
      Fixes: 1ebb7cc6 (" mm: munlock: batch NR_MLOCK zone state updates")
      Link: http://lkml.kernel.org/r/1495678405-54569-1-git-send-email-xieyisheng1@huawei.com
      
      Signed-off-by: default avatarYisheng Xie <xieyisheng1@huawei.com>
      Reported-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
      Tested-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Joern Engel <joern@logfs.org>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Michel Lespinasse <walken@google.com>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: Xishi Qiu <qiuxishi@huawei.com>
      Cc: zhongjiang <zhongjiang@huawei.com>
      Cc: Hanjun Guo <guohanjun@huawei.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>
      70feee0e
    • Punit Agrawal's avatar
      mm/migrate: fix refcount handling when !hugepage_migration_supported() · 30809f55
      Punit Agrawal authored
      On failing to migrate a page, soft_offline_huge_page() performs the
      necessary update to the hugepage ref-count.
      
      But when !hugepage_migration_supported() , unmap_and_move_hugepage()
      also decrements the page ref-count for the hugepage.  The combined
      behaviour leaves the ref-count in an inconsistent state.
      
      This leads to soft lockups when running the overcommitted hugepage test
      from mce-tests suite.
      
        Soft offlining pfn 0x83ed600 at process virtual address 0x400000000000
        soft offline: 0x83ed600: migration failed 1, type 1fffc00000008008 (uptodate|head)
        INFO: rcu_preempt detected stalls on CPUs/tasks:
         Tasks blocked on level-0 rcu_node (CPUs 0-7): P2715
          (detected by 7, t=5254 jiffies, g=963, c=962, q=321)
          thugetlb_overco R  running task        0  2715   2685 0x00000008
          Call trace:
            dump_backtrace+0x0/0x268
            show_stack+0x24/0x30
            sched_show_task+0x134/0x180
            rcu_print_detail_task_stall_rnp+0x54/0x7c
            rcu_check_callbacks+0xa74/0xb08
            update_process_times+0x34/0x60
            tick_sched_handle.isra.7+0x38/0x70
            tick_sched_timer+0x4c/0x98
            __hrtimer_run_queues+0xc0/0x300
            hrtimer_interrupt+0xac/0x228
            arch_timer_handler_phys+0x3c/0x50
            handle_percpu_devid_irq+0x8c/0x290
            generic_handle_irq+0x34/0x50
            __handle_domain_irq+0x68/0xc0
            gic_handle_irq+0x5c/0xb0
      
      Address this by changing the putback_active_hugepage() in
      soft_offline_huge_page() to putback_movable_pages().
      
      This only triggers on systems that enable memory failure handling
      (ARCH_SUPPORTS_MEMORY_FAILURE) but not hugepage migration
      (!ARCH_ENABLE_HUGEPAGE_MIGRATION).
      
      I imagine this wasn't triggered as there aren't many systems running
      this configuration.
      
      [akpm@linux-foundation.org: remove dead comment, per Naoya]
      Link: http://lkml.kernel.org/r/20170525135146.32011-1-punit.agrawal@arm.com
      
      Reported-by: default avatarManoj Iyer <manoj.iyer@canonical.com>
      Tested-by: default avatarManoj Iyer <manoj.iyer@canonical.com>
      Suggested-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Signed-off-by: default avatarPunit Agrawal <punit.agrawal@arm.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Wanpeng Li <wanpeng.li@hotmail.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: <stable@vger.kernel.org>	[3.14+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      30809f55
    • Ross Zwisler's avatar
      dax: fix race between colliding PMD & PTE entries · e2093926
      Ross Zwisler authored
      We currently have two related PMD vs PTE races in the DAX code.  These
      can both be easily triggered by having two threads reading and writing
      simultaneously to the same private mapping, with the key being that
      private mapping reads can be handled with PMDs but private mapping
      writes are always handled with PTEs so that we can COW.
      
      Here is the first race:
      
        CPU 0					CPU 1
      
        (private mapping write)
        __handle_mm_fault()
          create_huge_pmd() - FALLBACK
          handle_pte_fault()
            passes check for pmd_devmap()
      
      					(private mapping read)
      					__handle_mm_fault()
      					  create_huge_pmd()
      					    dax_iomap_pmd_fault() inserts PMD
      
            dax_iomap_pte_fault() does a PTE fault, but we already have a DAX PMD
            			  installed in our page tables at this spot.
      
      Here's the second race:
      
        CPU 0					CPU 1
      
        (private mapping read)
        __handle_mm_fault()
          passes check for pmd_none()
          create_huge_pmd()
            dax_iomap_pmd_fault() inserts PMD
      
        (private mapping write)
        __handle_mm_fault()
          create_huge_pmd() - FALLBACK
      					(private mapping read)
      					__handle_mm_fault()
      					  passes check for pmd_none()
      					  create_huge_pmd()
      
          handle_pte_fault()
            dax_iomap_pte_fault() inserts PTE
      					    dax_iomap_pmd_fault() inserts PMD,
      					       but we already have a PTE at
      					       this spot.
      
      The core of the issue is that while there is isolation between faults to
      the same range in the DAX fault handlers via our DAX entry locking,
      there is no isolation between faults in the code in mm/memory.c.  This
      means for instance that this code in __handle_mm_fault() can run:
      
      	if (pmd_none(*vmf.pmd) && transparent_hugepage_enabled(vma)) {
      		ret = create_huge_pmd(&vmf);
      
      But by the time we actually get to run the fault handler called by
      create_huge_pmd(), the PMD is no longer pmd_none() because a racing PTE
      fault has installed a normal PMD here as a parent.  This is the cause of
      the 2nd race.  The first race is similar - there is the following check
      in handle_pte_fault():
      
      	} else {
      		/* See comment in pte_alloc_one_map() */
      		if (pmd_devmap(*vmf->pmd) || pmd_trans_unstable(vmf->pmd))
      			return 0;
      
      So if a pmd_devmap() PMD (a DAX PMD) has been installed at vmf->pmd, we
      will bail and retry the fault.  This is correct, but there is nothing
      preventing the PMD from being installed after this check but before we
      actually get to the DAX PTE fault handlers.
      
      In my testing these races result in the following types of errors:
      
        BUG: Bad rss-counter state mm:ffff8800a817d280 idx:1 val:1
        BUG: non-zero nr_ptes on freeing mm: 15
      
      Fix this issue by having the DAX fault handlers verify that it is safe
      to continue their fault after they have taken an entry lock to block
      other racing faults.
      
      [ross.zwisler@linux.intel.com: improve fix for colliding PMD & PTE entries]
        Link: http://lkml.kernel.org/r/20170526195932.32178-1-ross.zwisler@linux.intel.com
      Link: http://lkml.kernel.org/r/20170522215749.23516-2-ross.zwisler@linux.intel.com
      
      Signed-off-by: default avatarRoss Zwisler <ross.zwisler@linux.intel.com>
      Reported-by: default avatarPawel Lebioda <pawel.lebioda@intel.com>
      Reviewed-by: default avatarJan Kara <jack@suse.cz>
      Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Matthew Wilcox <mawilcox@microsoft.com>
      Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Pawel Lebioda <pawel.lebioda@intel.com>
      Cc: Dave Jiang <dave.jiang@intel.com>
      Cc: Xiong Zhou <xzhou@redhat.com>
      Cc: Eryu Guan <eguan@redhat.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>
      e2093926
    • Ross Zwisler's avatar
      mm: avoid spurious 'bad pmd' warning messages · d0f0931d
      Ross Zwisler authored
      When the pmd_devmap() checks were added by 5c7fb56e ("mm, dax:
      dax-pmd vs thp-pmd vs hugetlbfs-pmd") to add better support for DAX huge
      pages, they were all added to the end of if() statements after existing
      pmd_trans_huge() checks.  So, things like:
      
        -       if (pmd_trans_huge(*pmd))
        +       if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))
      
      When further checks were added after pmd_trans_unstable() checks by
      commit 7267ec00 ("mm: postpone page table allocation until we have
      page to map") they were also added at the end of the conditional:
      
        +       if (pmd_trans_unstable(fe->pmd) || pmd_devmap(*fe->pmd))
      
      This ordering is fine for pmd_trans_huge(), but doesn't work for
      pmd_trans_unstable().  This is because DAX huge pages trip the bad_pmd()
      check inside of pmd_none_or_trans_huge_or_clear_bad() (called by
      pmd_trans_unstable()), which prints out a warning and returns 1.  So, we
      do end up doing the right thing, but only after spamming dmesg with
      suspicious looking messages:
      
        mm/pgtable-generic.c:39: bad pmd ffff8808daa49b88(84000001006000a5)
      
      Reorder these checks in a helper so that pmd_devmap() is checked first,
      avoiding the error messages, and add a comment explaining why the
      ordering is important.
      
      Fixes: commit 7267ec00 ("mm: postpone page table allocation until we have page to map")
      Link: http://lkml.kernel.org/r/20170522215749.23516-1-ross.zwisler@linux.intel.com
      
      Signed-off-by: default avatarRoss Zwisler <ross.zwisler@linux.intel.com>
      Reviewed-by: default avatarJan Kara <jack@suse.cz>
      Cc: Pawel Lebioda <pawel.lebioda@intel.com>
      Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Matthew Wilcox <mawilcox@microsoft.com>
      Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: Dave Jiang <dave.jiang@intel.com>
      Cc: Xiong Zhou <xzhou@redhat.com>
      Cc: Eryu Guan <eguan@redhat.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>
      d0f0931d
    • Tetsuo Handa's avatar
      mm/page_alloc.c: make sure OOM victim can try allocations with no watermarks once · c288983d
      Tetsuo Handa authored
      Roman Gushchin has reported that the OOM killer can trivially selects
      next OOM victim when a thread doing memory allocation from page fault
      path was selected as first OOM victim.
      
          allocate invoked oom-killer: gfp_mask=0x14280ca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO), nodemask=(null),  order=0, oom_score_adj=0
          allocate cpuset=/ mems_allowed=0
          CPU: 1 PID: 492 Comm: allocate Not tainted 4.12.0-rc1-mm1+ #181
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
          Call Trace:
           oom_kill_process+0x219/0x3e0
           out_of_memory+0x11d/0x480
           __alloc_pages_slowpath+0xc84/0xd40
           __alloc_pages_nodemask+0x245/0x260
           alloc_pages_vma+0xa2/0x270
           __handle_mm_fault+0xca9/0x10c0
           handle_mm_fault+0xf3/0x210
           __do_page_fault+0x240/0x4e0
           trace_do_page_fault+0x37/0xe0
           do_async_page_fault+0x19/0x70
           async_page_fault+0x28/0x30
          ...
          Out of memory: Kill process 492 (allocate) score 899 or sacrifice child
          Killed process 492 (allocate) total-vm:2052368kB, anon-rss:1894576kB, file-rss:4kB, shmem-rss:0kB
          allocate: page allocation failure: order:0, mode:0x14280ca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO), nodemask=(null)
          allocate cpuset=/ mems_allowed=0
          CPU: 1 PID: 492 Comm: allocate Not tainted 4.12.0-rc1-mm1+ #181
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
          Call Trace:
           __alloc_pages_slowpath+0xd32/0xd40
           __alloc_pages_nodemask+0x245/0x260
           alloc_pages_vma+0xa2/0x270
           __handle_mm_fault+0xca9/0x10c0
           handle_mm_fault+0xf3/0x210
           __do_page_fault+0x240/0x4e0
           trace_do_page_fault+0x37/0xe0
           do_async_page_fault+0x19/0x70
           async_page_fault+0x28/0x30
          ...
          oom_reaper: reaped process 492 (allocate), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB
          ...
          allocate invoked oom-killer: gfp_mask=0x0(), nodemask=(null),  order=0, oom_score_adj=0
          allocate cpuset=/ mems_allowed=0
          CPU: 1 PID: 492 Comm: allocate Not tainted 4.12.0-rc1-mm1+ #181
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
          Call Trace:
           oom_kill_process+0x219/0x3e0
           out_of_memory+0x11d/0x480
           pagefault_out_of_memory+0x68/0x80
           mm_fault_error+0x8f/0x190
           ? handle_mm_fault+0xf3/0x210
           __do_page_fault+0x4b2/0x4e0
           trace_do_page_fault+0x37/0xe0
           do_async_page_fault+0x19/0x70
           async_page_fault+0x28/0x30
          ...
          Out of memory: Kill process 233 (firewalld) score 10 or sacrifice child
          Killed process 233 (firewalld) total-vm:246076kB, anon-rss:20956kB, file-rss:0kB, shmem-rss:0kB
      
      There is a race window that the OOM reaper completes reclaiming the
      first victim's memory while nothing but mutex_trylock() prevents the
      first victim from calling out_of_memory() from pagefault_out_of_memory()
      after memory allocation for page fault path failed due to being selected
      as an OOM victim.
      
      This is a side effect of commit 9a67f648 ("mm: consolidate
      GFP_NOFAIL checks in the allocator slowpath") because that commit
      silently changed the behavior from
      
          /* Avoid allocations with no watermarks from looping endlessly */
      
      to
      
          /*
           * Give up allocations without trying memory reserves if selected
           * as an OOM victim
           */
      
      in __alloc_pages_slowpath() by moving the location to check TIF_MEMDIE
      flag.  I have noticed this change but I didn't post a patch because I
      thought it is an acceptable change other than noise by warn_alloc()
      because !__GFP_NOFAIL allocations are allowed to fail.  But we
      overlooked that failing memory allocation from page fault path makes
      difference due to the race window explained above.
      
      While it might be possible to add a check to pagefault_out_of_memory()
      that prevents the first victim from calling out_of_memory() or remove
      out_of_memory() from pagefault_out_of_memory(), changing
      pagefault_out_of_memory() does not suppress noise by warn_alloc() when
      allocating thread was selected as an OOM victim.  There is little point
      with printing similar backtraces and memory information from both
      out_of_memory() and warn_alloc().
      
      Instead, if we guarantee that current thread can try allocations with no
      watermarks once when current thread looping inside
      __alloc_pages_slowpath() was selected as an OOM victim, we can follow "who
      can use memory reserves" rules and suppress noise by warn_alloc() and
      prevent memory allocations from page fault path from calling
      pagefault_out_of_memory().
      
      If we take the comment literally, this patch would do
      
        -    if (test_thread_flag(TIF_MEMDIE))
        -        goto nopage;
        +    if (alloc_flags == ALLOC_NO_WATERMARKS || (gfp_mask & __GFP_NOMEMALLOC))
        +        goto nopage;
      
      because gfp_pfmemalloc_allowed() returns false if __GFP_NOMEMALLOC is
      given.  But if I recall correctly (I couldn't find the message), the
      condition is meant to apply to only OOM victims despite the comment.
      Therefore, this patch preserves TIF_MEMDIE check.
      
      Fixes: 9a67f648 ("mm: consolidate GFP_NOFAIL checks in the allocator slowpath")
      Link: http://lkml.kernel.org/r/201705192112.IAF69238.OQOHSJLFOFFMtV@I-love.SAKURA.ne.jp
      
      Signed-off-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Reported-by: default avatarRoman Gushchin <guro@fb.com>
      Tested-by: default avatarRoman Gushchin <guro@fb.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
      Cc: <stable@vger.kernel.org>	[4.11]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c288983d
    • Nicolas Iooss's avatar
      pcmcia: remove left-over %Z format · ff5a2016
      Nicolas Iooss authored
      Commit 5b5e0928 ("lib/vsprintf.c: remove %Z support") removed some
      usages of format %Z but forgot "%.2Zx".  This makes clang 4.0 reports a
      -Wformat-extra-args warning because it does not know about %Z.
      
      Replace %Z with %z.
      
      Link: http://lkml.kernel.org/r/20170520090946.22562-1-nicolas.iooss_linux@m4x.org
      
      Signed-off-by: default avatarNicolas Iooss <nicolas.iooss_linux@m4x.org>
      Cc: Harald Welte <laforge@gnumonks.org>
      Cc: Alexey Dobriyan <adobriyan@gmail.com>
      Cc: <stable@vger.kernel.org>	[4.11+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ff5a2016
    • Thomas Gleixner's avatar
      slub/memcg: cure the brainless abuse of sysfs attributes · 478fe303
      Thomas Gleixner authored
      memcg_propagate_slab_attrs() abuses the sysfs attribute file functions
      to propagate settings from the root kmem_cache to a newly created
      kmem_cache.  It does that with:
      
           attr->show(root, buf);
           attr->store(new, buf, strlen(bug);
      
      Aside of being a lazy and absurd hackery this is broken because it does
      not check the return value of the show() function.
      
      Some of the show() functions return 0 w/o touching the buffer.  That
      means in such a case the store function is called with the stale content
      of the previous show().  That causes nonsense like invoking
      kmem_cache_shrink() on a newly created kmem_cache.  In the worst case it
      would cause handing in an uninitialized buffer.
      
      This should be rewritten proper by adding a propagate() callback to
      those slub_attributes which must be propagated and avoid that insane
      conversion to and from ASCII, but that's too large for a hot fix.
      
      Check at least the return value of the show() function, so calling
      store() with stale content is prevented.
      
      Steven said:
       "It can cause a deadlock with get_online_cpus() that has been uncovered
        by recent cpu hotplug and lockdep changes that Thomas and Peter have
        been doing.
      
           Possible unsafe locking scenario:
      
                 CPU0                    CPU1
                 ----                    ----
            lock(cpu_hotplug.lock);
                                         lock(slab_mutex);
                                         lock(cpu_hotplug.lock);
            lock(slab_mutex);
      
           *** DEADLOCK ***"
      
      Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1705201244540.2255@nanos
      
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Reported-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Acked-by: default avatarDavid Rientjes <rientjes@google.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      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>
      478fe303
    • Florian Fainelli's avatar
      initramfs: fix disabling of initramfs (and its compression) · 57ddfdaa
      Florian Fainelli authored
      Commit db2aa7fd ("initramfs: allow again choice of the embedded
      initram compression algorithm") introduced the possibility to select the
      initramfs compression algorithm from Kconfig and while this is a nice
      feature it broke the use case described below.
      
      Here is what my build system does:
      
       - kernel is initially configured not to have an initramfs included
      
       - build the user space root file system
      
       - re-configure the kernel to have an initramfs included
         (CONFIG_INITRAMFS_SOURCE="/path/to/romfs") and set relevant
         CONFIG_INITRAMFS options, in my case, no compression option
         (CONFIG_INITRAMFS_COMPRESSION_NONE)
      
       - kernel is re-built with these options -> kernel+initramfs image is
         copied
      
       - kernel is re-built again without these options -> kernel image is
         copied
      
      Building a kernel without an initramfs means setting this option:
      
        CONFIG_INITRAMFS_SOURCE="" (and this one only)
      
      whereas building a kernel with an initramfs means setting these options:
      
        CONFIG_INITRAMFS_SOURCE="/home/fainelli/work/uclinux-rootfs/romfs /home/fainelli/work/uclinux-rootfs/misc/initramfs.dev"
        CONFIG_INITRAMFS_ROOT_UID=1000
        CONFIG_INITRAMFS_ROOT_GID=1000
        CONFIG_INITRAMFS_COMPRESSION_NONE=y
        CONFIG_INITRAMFS_COMPRESSION=""
      
      Commit db2aa7fd ("initramfs: allow again choice of the embedded
      initram compression algorithm") is problematic because
      CONFIG_INITRAMFS_COMPRESSION which is used to determine the
      initramfs_data.cpio extension/compression is a string, and due to how
      Kconfig works it will evaluate in order, how to assign it.
      
      Setting CONFIG_INITRAMFS_COMPRESSION_NONE with CONFIG_INITRAMFS_SOURCE=""
      cannot possibly work (because of the depends on INITRAMFS_SOURCE!=""
      imposed on CONFIG_INITRAMFS_COMPRESSION ) yet we still get
      CONFIG_INITRAMFS_COMPRESSION assigned to ".gz" because CONFIG_RD_GZIP=y
      is set in my kernel, even when there is no initramfs being built.
      
      So we basically end-up generating two initramfs_data.cpio* files, one
      without extension, and one with .gz.  This causes usr/Makefile to track
      usr/initramfs_data.cpio.gz, and not usr/initramfs_data.cpio anymore,
      that is also largely problematic after 9e3596b0 ("kbuild:
      initramfs cleanup, set target from Kconfig") because we used to track
      all possible initramfs_data files in the $(targets) variable before that
      commit.
      
      The end result is that the kernel with an initramfs clearly does not
      contain what we expect it to, it has a stale initramfs_data.cpio file
      built into it, and we keep re-generating an initramfs_data.cpio.gz file
      which is not the one that we want to include in the kernel image proper.
      
      The fix consists in hiding CONFIG_INITRAMFS_COMPRESSION when
      CONFIG_INITRAMFS_SOURCE="".  This puts us back in a state to the
      pre-4.10 behavior where we can properly disable and re-enable initramfs
      within the same kernel .config file, and be in control of what
      CONFIG_INITRAMFS_COMPRESSION is set to.
      
      Fixes: db2aa7fd ("initramfs: allow again choice of the embedded initram compression algorithm")
      Fixes: 9e3596b0 ("kbuild: initramfs cleanup, set target from Kconfig")
      Link: http://lkml.kernel.org/r/20170521033337.6197-1-f.fainelli@gmail.com
      
      Signed-off-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
      Acked-by: default avatarNicholas Piggin <npiggin@gmail.com>
      Cc: P J P <ppandit@redhat.com>
      Cc: Paul Bolle <pebolle@tiscali.nl>
      Cc: Michal Marek <mmarek@suse.cz>
      Cc: Daniel Thompson <daniel.thompson@linaro.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      57ddfdaa
    • Michal Hocko's avatar
      mm: clarify why we want kmalloc before falling backto vmallock · 4f4f2ba9
      Michal Hocko authored
      While converting drm_[cm]alloc* helpers to kvmalloc* variants Chris
      Wilson has wondered why we want to try kmalloc before vmalloc fallback
      even for larger allocations requests.  Let's clarify that one larger
      physically contiguous block is less likely to fragment memory than many
      scattered pages which can prevent more large blocks from being created.
      
      [akpm@linux-foundation.org: coding-style fixes]
      Link: http://lkml.kernel.org/r/20170517080932.21423-1-mhocko@kernel.org
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Suggested-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
      Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
      Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      4f4f2ba9
    • Matthias Kaehlcke's avatar
      frv: declare jiffies to be located in the .data section · 60b0a8c3
      Matthias Kaehlcke authored
      Commit 7c30f352 ("jiffies.h: declare jiffies and jiffies_64 with
      ____cacheline_aligned_in_smp") removed a section specification from the
      jiffies declaration that caused conflicts on some platforms.
      
      Unfortunately this change broke the build for frv:
      
        kernel/built-in.o: In function `__do_softirq': (.text+0x6460): relocation truncated to fit: R_FRV_GPREL12 against symbol
            `jiffies' defined in *ABS* section in .tmp_vmlinux1
        kernel/built-in.o: In function `__do_softirq': (.text+0x6574): relocation truncated to fit: R_FRV_GPREL12 against symbol
            `jiffies' defined in *ABS* section in .tmp_vmlinux1
        kernel/built-in.o: In function `pwq_activate_delayed_work': workqueue.c:(.text+0x15b9c): relocation truncated to fit: R_FRV_GPREL12 against
            symbol `jiffies' defined in *ABS* section in .tmp_vmlinux1
        ...
      
      Add __jiffy_arch_data to the declaration of jiffies and use it on frv to
      include the section specification.  For all other platforms
      __jiffy_arch_data (currently) has no effect.
      
      Fixes: 7c30f352 ("jiffies.h: declare jiffies and jiffies_64 with ____cacheline_aligned_in_smp")
      Link: http://lkml.kernel.org/r/20170516221333.177280-1-mka@chromium.org
      
      Signed-off-by: default avatarMatthias Kaehlcke <mka@chromium.org>
      Reported-by: default avatarGuenter Roeck <linux@roeck-us.net>
      Tested-by: default avatarGuenter Roeck <linux@roeck-us.net>
      Reviewed-by: default avatarDavid Howells <dhowells@redhat.com>
      Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      60b0a8c3
    • Michal Hocko's avatar
      include/linux/gfp.h: fix ___GFP_NOLOCKDEP value · 1bde33e0
      Michal Hocko authored
      Igor Stoppa has noticed that __GFP_NOLOCKDEP can use a lower bit.  At
      the time commit 7e784422 ("lockdep: allow to disable reclaim lockup
      detection") was written we still had __GFP_OTHER_NODE but I have removed
      it in commit 41b6167e ("mm: get rid of __GFP_OTHER_NODE") and forgot
      to lower the bit value.
      
      The current value is outside of __GFP_BITS_SHIFT so it cannot be used
      actually.
      
      Fixes: 7e784422
      
       ("lockdep: allow to disable reclaim lockup detection")
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reported-by: default avatarIgor Stoppa <igor.stoppa@nokia.com>
      Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1bde33e0
    • Andrea Arcangeli's avatar
      ksm: prevent crash after write_protect_page fails · a7306c34
      Andrea Arcangeli authored
      "err" needs to be left set to -EFAULT if split_huge_page succeeds.
      Otherwise if "err" gets clobbered with zero and write_protect_page
      fails, try_to_merge_one_page() will succeed instead of returning -EFAULT
      and then try_to_merge_with_ksm_page() will continue thinking kpage is a
      PageKsm when in fact it's still an anonymous page.  Eventually it'll
      crash in page_add_anon_rmap.
      
      This has been reproduced on Fedora25 kernel but I can reproduce with
      upstream too.
      
      The bug was introduced in commit f765f540 ("ksm: prepare to new THP
      semantics") introduced in v4.5.
      
          page:fffff67546ce1cc0 count:4 mapcount:2 mapping:ffffa094551e36e1 index:0x7f0f46673
          flags: 0x2ffffc0004007c(referenced|uptodate|dirty|lru|active|swapbacked)
          page dumped because: VM_BUG_ON_PAGE(!PageLocked(page))
          page->mem_cgroup:ffffa09674bf0000
          ------------[ cut here ]------------
          kernel BUG at mm/rmap.c:1222!
          CPU: 1 PID: 76 Comm: ksmd Not tainted 4.9.3-200.fc25.x86_64 #1
          RIP: do_page_add_anon_rmap+0x1c4/0x240
          Call Trace:
            page_add_anon_rmap+0x18/0x20
            try_to_merge_with_ksm_page+0x50b/0x780
            ksm_scan_thread+0x1211/0x1410
            ? prepare_to_wait_event+0x100/0x100
            ? try_to_merge_with_ksm_page+0x780/0x780
            kthread+0xd9/0xf0
            ? kthread_park+0x60/0x60
            ret_from_fork+0x25/0x30
      
      Fixes: f765f540 ("ksm: prepare to new THP semantics")
      Link: http://lkml.kernel.org/r/20170513131040.21732-1-aarcange@redhat.com
      
      Signed-off-by: default avatarAndrea Arcangeli <aarcange@redhat.com>
      Reported-by: default avatarFederico Simoncelli <fsimonce@redhat.com>
      Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Hugh Dickins <hughd@google.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>
      a7306c34
    • Rafael J. Wysocki's avatar
      Merge branches 'acpi-button', 'acpica' and 'acpi-sysfs' · 60319130
      Rafael J. Wysocki authored
      * acpi-button:
        Revert "ACPI / button: Change default behavior to lid_init_state=open"
      
      * acpica:
        ACPICA: Tables: Fix regression introduced by a too early mechanism enabling
      
      * acpi-sysfs:
        ACPI / sysfs: fix acpi_get_table() leak / acpi-sysfs denial of service
      60319130
    • Rafael J. Wysocki's avatar
      Merge branch 'pm-cpufreq' · bb5710e7
      Rafael J. Wysocki authored
      * pm-cpufreq:
        cpufreq: kirkwood-cpufreq:- Handle return value of clk_prepare_enable()
        cpufreq: cpufreq_register_driver() should return -ENODEV if init fails
      bb5710e7
    • Linus Torvalds's avatar
      Merge tag 'xfs-4.12-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux · e6e6d074
      Linus Torvalds authored
      Pull XFS fix from Darrick Wong:
       "I've one more bugfix for you for 4.12-rc4: Fix an unmount hang due to
        a race in io buffer accounting"
      
      * tag 'xfs-4.12-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
        xfs: use ->b_state to fix buffer I/O accounting release race
      e6e6d074