1. 03 Feb, 2018 2 commits
  2. 01 Feb, 2018 38 commits
    • Alexander Monakov's avatar
      net: pxa168_eth: add netconsole support · 743ffffe
      Alexander Monakov authored
      
      
      This implements ndo_poll_controller callback which is necessary to
      enable netconsole.
      
      Signed-off-by: default avatarAlexander Monakov <amonakov@ispras.ru>
      Cc: Russell King <rmk+kernel@arm.linux.org.uk>
      Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
      Cc: Florian Fainelli <f.fainelli@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      743ffffe
    • Eric Dumazet's avatar
      net: igmp: add a missing rcu locking section · e7aadb27
      Eric Dumazet authored
      Newly added igmpv3_get_srcaddr() needs to be called under rcu lock.
      
      Timer callbacks do not ensure this locking.
      
      =============================
      WARNING: suspicious RCU usage
      4.15.0+ #200 Not tainted
      -----------------------------
      ./include/linux/inetdevice.h:216 suspicious rcu_dereference_check() usage!
      
      other info that might help us debug this:
      
      rcu_scheduler_active = 2, debug_locks = 1
      3 locks held by syzkaller616973/4074:
       #0:  (&mm->mmap_sem){++++}, at: [<00000000bfce669e>] __do_page_fault+0x32d/0xc90 arch/x86/mm/fault.c:1355
       #1:  ((&im->timer)){+.-.}, at: [<00000000619d2f71>] lockdep_copy_map include/linux/lockdep.h:178 [inline]
       #1:  ((&im->timer)){+.-.}, at: [<00000000619d2f71>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1316
       #2:  (&(&im->lock)->rlock){+.-.}, at: [<000000005f833c5c>] spin_lock_bh include/linux/spinlock.h:315 [inline]
       #2:  (&(&im->lock)->rlock){+.-.}, at: [<000000005f833c5c>] igmpv3_send_report+0x98/0x5b0 net/ipv4/igmp.c:600
      
      stack backtrace:
      CPU: 0 PID: 4074 Comm: syzkaller616973 Not tainted 4.15.0+ #200
      Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
      Call Trace:
       <IRQ>
       __dump_stack lib/dump_stack.c:17 [inline]
       dump_stack+0x194/0x257 lib/dump_stack.c:53
       lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4592
       __in_dev_get_rcu include/linux/inetdevice.h:216 [inline]
       igmpv3_get_srcaddr net/ipv4/igmp.c:329 [inline]
       igmpv3_newpack+0xeef/0x12e0 net/ipv4/igmp.c:389
       add_grhead.isra.27+0x235/0x300 net/ipv4/igmp.c:432
       add_grec+0xbd3/0x1170 net/ipv4/igmp.c:565
       igmpv3_send_report+0xd5/0x5b0 net/ipv4/igmp.c:605
       igmp_send_report+0xc43/0x1050 net/ipv4/igmp.c:722
       igmp_timer_expire+0x322/0x5c0 net/ipv4/igmp.c:831
       call_timer_fn+0x228/0x820 kernel/time/timer.c:1326
       expire_timers kernel/time/timer.c:1363 [inline]
       __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666
       run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692
       __do_softirq+0x2d7/0xb85 kernel/softirq.c:285
       invoke_softirq kernel/softirq.c:365 [inline]
       irq_exit+0x1cc/0x200 kernel/softirq.c:405
       exiting_irq arch/x86/include/asm/apic.h:541 [inline]
       smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052
       apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:938
      
      Fixes: a46182b0
      
       ("net: igmp: Use correct source address on IGMPv3 reports")
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
      
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e7aadb27
    • Desnes Augusto Nunes do Rosario's avatar
      ibmvnic: fix firmware version when no firmware level has been provided by the VIOS server · a107311d
      Desnes Augusto Nunes do Rosario authored
      Older versions of VIOS servers do not send the firmware level in the VPD
      buffer for the ibmvnic driver. Thus, not only the current message is mis-
      leading but the firmware version in the ethtool will be NULL. Therefore,
      this patch fixes the firmware string and its warning.
      
      Fixes: 4e6759be
      
       ("ibmvnic: Feature implementation of VPD for the ibmvnic driver")
      Signed-off-by: default avatarDesnes A. Nunes do Rosario <desnesn@linux.vnet.ibm.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a107311d
    • Colin Ian King's avatar
      vmxnet3: remove redundant initialization of pointer 'rq' · 5e264e2b
      Colin Ian King authored
      
      
      Pointer rq is being initialized but this value is never read, it
      is being updated inside a for-loop. Remove the initialization and
      move it into the scope of the for-loop.
      
      Cleans up clang warning:
      drivers/net/vmxnet3/vmxnet3_drv.c:2763:27: warning: Value stored
      to 'rq' during its initialization is never read
      
      Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
      Acked-by: default avatarShrikrishna Khare <skhare@vmware.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      5e264e2b
    • Colin Ian King's avatar
      lan78xx: remove redundant initialization of pointer 'phydev' · 3b51cc75
      Colin Ian King authored
      
      
      Pointer phydev is initialized and this value is never read, phydev
      is immediately updated to a new value, hence this initialization
      is redundant and can be removed
      
      Cleans up clang warning:
      drivers/net/usb/lan78xx.c:2009:21: warning: Value stored to 'phydev'
      during its initialization is never read
      
      Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3b51cc75
    • Colin Ian King's avatar
      net: jme: remove unused initialization of 'rxdesc' · f14d244f
      Colin Ian King authored
      
      
      Pointer rxdesc is assigned a value that is never read, it is overwritten
      by a new assignment inside a while loop hence the initial assignment
      is redundant and can be removed.
      
      Cleans up clang warning:
      drivers/net/ethernet/jme.c:1074:17: warning: Value stored to 'rxdesc'
      during its initialization is never read
      
      Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f14d244f
    • David S. Miller's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf · b9a40729
      David S. Miller authored
      
      
      Pablo Neira Ayuso says:
      
      ====================
      Netfilter fixes for net
      
      The following patchset contains Netfilter fixes for your net tree,
      they are:
      
      1) Fix OOM that syskaller triggers with ipt_replace.size = -1 and
         IPT_SO_SET_REPLACE socket option, from Dmitry Vyukov.
      
      2) Check for too long extension name in xt_request_find_{match|target}
         that result in out-of-bound reads, from Eric Dumazet.
      
      3) Fix memory exhaustion bug in ipset hash:*net* types when adding ranges
         that look like x.x.x.x-255.255.255.255, from Jozsef Kadlecsik.
      
      4) Fix pointer leaks to userspace in x_tables, from Dmitry Vyukov.
      
      5) Insufficient sanity checks in clusterip_tg_check(), also from Dmitry.
      ====================
      
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b9a40729
    • Christian Brauner's avatar
      rtnetlink: remove check for IFLA_IF_NETNSID · 7973bfd8
      Christian Brauner authored
      RTM_NEWLINK supports the IFLA_IF_NETNSID property since
      5bb8ed07
      
       so we should not error out
      when it is passed.
      
      Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      7973bfd8
    • Jiri Pirko's avatar
      rocker: fix possible null pointer dereference in rocker_router_fib_event_work · a83165f0
      Jiri Pirko authored
      Currently, rocker user may experience following null pointer
      derefence bug:
      
      [    3.062141] BUG: unable to handle kernel NULL pointer dereference at 00000000000000d0
      [    3.065163] IP: rocker_router_fib_event_work+0x36/0x110 [rocker]
      
      The problem is uninitialized rocker->wops pointer that is initialized
      only with the first initialized port. So move the port initialization
      before registering the fib events.
      
      Fixes: 936bd486
      
       ("rocker: use FIB notifications instead of switchdev calls")
      Signed-off-by: default avatarJiri Pirko <jiri@mellanox.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a83165f0
    • Geert Uytterhoeven's avatar
      inet: Avoid unitialized variable warning in inet_unhash() · 0ba98718
      Geert Uytterhoeven authored
      
      
      With gcc-4.1.2:
      
          net/ipv4/inet_hashtables.c: In function ‘inet_unhash’:
          net/ipv4/inet_hashtables.c:628: warning: ‘ilb’ may be used uninitialized in this function
      
      While this is a false positive, it can easily be avoided by using the
      pointer itself as the canary variable.
      
      Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0ba98718
    • Geert Uytterhoeven's avatar
      net: bridge: Fix uninitialized error in br_fdb_sync_static() · 367dc658
      Geert Uytterhoeven authored
      With gcc-4.1.2.:
      
          net/bridge/br_fdb.c: In function ‘br_fdb_sync_static’:
          net/bridge/br_fdb.c:996: warning: ‘err’ may be used uninitialized in this function
      
      Indeed, if the list is empty, err will be uninitialized, and will be
      propagated up as the function return value.
      
      Fix this by preinitializing err to zero.
      
      Fixes: eb793583
      
       ("net: bridge: use rhashtable for fdbs")
      Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Acked-by: default avatarNikolay Aleksandrov <nikolay@cumulusnetworks.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      367dc658
    • Ed Swierk's avatar
      openvswitch: Remove padding from packet before L3+ conntrack processing · 9382fe71
      Ed Swierk authored
      
      
      IPv4 and IPv6 packets may arrive with lower-layer padding that is not
      included in the L3 length. For example, a short IPv4 packet may have
      up to 6 bytes of padding following the IP payload when received on an
      Ethernet device with a minimum packet length of 64 bytes.
      
      Higher-layer processing functions in netfilter (e.g. nf_ip_checksum(),
      and help() in nf_conntrack_ftp) assume skb->len reflects the length of
      the L3 header and payload, rather than referring back to
      ip_hdr->tot_len or ipv6_hdr->payload_len, and get confused by
      lower-layer padding.
      
      In the normal IPv4 receive path, ip_rcv() trims the packet to
      ip_hdr->tot_len before invoking netfilter hooks. In the IPv6 receive
      path, ip6_rcv() does the same using ipv6_hdr->payload_len. Similarly
      in the br_netfilter receive path, br_validate_ipv4() and
      br_validate_ipv6() trim the packet to the L3 length before invoking
      netfilter hooks.
      
      Currently in the OVS conntrack receive path, ovs_ct_execute() pulls
      the skb to the L3 header but does not trim it to the L3 length before
      calling nf_conntrack_in(NF_INET_PRE_ROUTING). When
      nf_conntrack_proto_tcp encounters a packet with lower-layer padding,
      nf_ip_checksum() fails causing a "nf_ct_tcp: bad TCP checksum" log
      message. While extra zero bytes don't affect the checksum, the length
      in the IP pseudoheader does. That length is based on skb->len, and
      without trimming, it doesn't match the length the sender used when
      computing the checksum.
      
      In ovs_ct_execute(), trim the skb to the L3 length before higher-layer
      processing.
      
      Signed-off-by: default avatarEd Swierk <eswierk@skyportsystems.com>
      Acked-by: default avatarPravin B Shelar <pshelar@ovn.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9382fe71
    • Neal Cardwell's avatar
      tcp_bbr: fix pacing_gain to always be unity when using lt_bw · 3aff3b4b
      Neal Cardwell authored
      This commit fixes the pacing_gain to remain at BBR_UNIT (1.0) when
      using lt_bw and returning from the PROBE_RTT state to PROBE_BW.
      
      Previously, when using lt_bw, upon exiting PROBE_RTT and entering
      PROBE_BW the bbr_reset_probe_bw_mode() code could sometimes randomly
      end up with a cycle_idx of 0 and hence have bbr_advance_cycle_phase()
      set a pacing gain above 1.0. In such cases this would result in a
      pacing rate that is 1.25x higher than intended, potentially resulting
      in a high loss rate for a little while until we stop using the lt_bw a
      bit later.
      
      This commit is a stable candidate for kernels back as far as 4.9.
      
      Fixes: 0f8782ea
      
       ("tcp_bbr: add BBR congestion control")
      Signed-off-by: default avatarNeal Cardwell <ncardwell@google.com>
      Signed-off-by: default avatarYuchung Cheng <ycheng@google.com>
      Signed-off-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
      Reported-by: default avatarBeyers Cronje <bcronje@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3aff3b4b
    • Colin Ian King's avatar
      be2net: remove redundant initialization of 'head' and pointer txq · 2e85283d
      Colin Ian King authored
      
      
      Variable head is initialized to a value that is never read and is
      being updated to a new value a few lines later, hence this
      initialization is redundant and can be safely removed as well
      as the now unused pointer txq.
      
      Cleans up clang warning:
      drivers/net/ethernet/emulex/benet/be_main.c:996:6: warning: Value
      stored to 'head' during its initialization is never read
      
      Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2e85283d
    • David S. Miller's avatar
      Merge branch 'bnx2x-disable-GSO-on-too-large-packets' · 26c26ab0
      David S. Miller authored
      Daniel Axtens says:
      
      ====================
      bnx2x: disable GSO on too-large packets
      
      We observed a case where a packet received on an ibmveth device had a
      GSO size of around 10kB. This was forwarded by Open vSwitch to a bnx2x
      device, where it caused a firmware assert. This is described in detail
      at [0].
      
      Ultimately we want a fix in the core, but that is very tricky to
      backport. So for now, just stop the bnx2x driver from crashing.
      
      When net-next re-opens I will send the fix to the core and a revert
      for this.
      
      v4 changes:
        - fix compilation error with EXPORTs (patch 1)
        - only do slow test if gso_size is greater than 9000 bytes (patch 2)
      
      Thanks,
      Daniel
      
      [0]: https://patchwork.ozlabs.org/patch/859410/
      
      
      ====================
      
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      26c26ab0
    • Daniel Axtens's avatar
      bnx2x: disable GSO where gso_size is too big for hardware · 8914a595
      Daniel Axtens authored
      
      
      If a bnx2x card is passed a GSO packet with a gso_size larger than
      ~9700 bytes, it will cause a firmware error that will bring the card
      down:
      
      bnx2x: [bnx2x_attn_int_deasserted3:4323(enP24p1s0f0)]MC assert!
      bnx2x: [bnx2x_mc_assert:720(enP24p1s0f0)]XSTORM_ASSERT_LIST_INDEX 0x2
      bnx2x: [bnx2x_mc_assert:736(enP24p1s0f0)]XSTORM_ASSERT_INDEX 0x0 = 0x00000000 0x25e43e47 0x00463e01 0x00010052
      bnx2x: [bnx2x_mc_assert:750(enP24p1s0f0)]Chip Revision: everest3, FW Version: 7_13_1
      ... (dump of values continues) ...
      
      Detect when the mac length of a GSO packet is greater than the maximum
      packet size (9700 bytes) and disable GSO.
      
      Signed-off-by: default avatarDaniel Axtens <dja@axtens.net>
      Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8914a595
    • Daniel Axtens's avatar
      net: create skb_gso_validate_mac_len() · 2b16f048
      Daniel Axtens authored
      
      
      If you take a GSO skb, and split it into packets, will the MAC
      length (L2 + L3 + L4 headers + payload) of those packets be small
      enough to fit within a given length?
      
      Move skb_gso_mac_seglen() to skbuff.h with other related functions
      like skb_gso_network_seglen() so we can use it, and then create
      skb_gso_validate_mac_len to do the full calculation.
      
      Signed-off-by: default avatarDaniel Axtens <dja@axtens.net>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2b16f048
    • Linus Torvalds's avatar
      Merge tag 'docs-4.16' of git://git.lwn.net/linux · 255442c9
      Linus Torvalds authored
      Pull documentation updates from Jonathan Corbet:
       "Documentation updates for 4.16.
      
        New stuff includes refcount_t documentation, errseq documentation,
        kernel-doc support for nested structure definitions, the removal of
        lots of crufty kernel-doc support for unused formats, SPDX tag
        documentation, the beginnings of a manual for subsystem maintainers,
        and lots of fixes and updates.
      
        As usual, some of the changesets reach outside of Documentation/ to
        effect kerneldoc comment fixes. It also adds the new LICENSES
        directory, of which Thomas promises I do not need to be the
        maintainer"
      
      * tag 'docs-4.16' of git://git.lwn.net/linux: (65 commits)
        linux-next: docs-rst: Fix typos in kfigure.py
        linux-next: DOC: HWPOISON: Fix path to debugfs in hwpoison.txt
        Documentation: Fix misconversion of #if
        docs: add index entry for networking/msg_zerocopy
        Documentation: security/credentials.rst: explain need to sort group_list
        LICENSES: Add MPL-1.1 license
        LICENSES: Add the GPL 1.0 license
        LICENSES: Add Linux syscall note exception
        LICENSES: Add the MIT license
        LICENSES: Add the BSD-3-clause "Clear" license
        LICENSES: Add the BSD 3-clause "New" or "Revised" License
        LICENSES: Add the BSD 2-clause "Simplified" license
        LICENSES: Add the LGPL-2.1 license
        LICENSES: Add the LGPL 2.0 license
        LICENSES: Add the GPL 2.0 license
        Documentation: Add license-rules.rst to describe how to properly identify file licenses
        scripts: kernel_doc: better handle show warnings logic
        fs/*/Kconfig: drop links to 404-compliant http://acl.bestbits.at
        doc: md: Fix a file name to md-fault.c in fault-injection.txt
        errseq: Add to documentation tree
        ...
      255442c9
    • Linus Torvalds's avatar
      Merge branch 'work.vmci' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs · d76e0a05
      Linus Torvalds authored
      Pull vmci iov_iter updates from Al Viro:
       "Get rid of "is it an iovec or an entire array?" flags in vmxi - just
        use iov_iter. Simplifies the living hell out of that code..."
      
      * 'work.vmci' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
        vmci: the same on the send side...
        vmci: simplify qp_dequeue_locked()
        vmci: get rid of qp_memcpy_from_queue()
        vmci: fix buf_size in case of iovec-based accesses
      d76e0a05
    • Linus Torvalds's avatar
      Merge branch 'work.whack-a-mole' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs · 40b9672a
      Linus Torvalds authored
      Pull asm/uaccess.h whack-a-mole from Al Viro:
       "It's linux/uaccess.h, damnit... Oh, well - eventually they'll stop
        cropping up..."
      
      * 'work.whack-a-mole' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
        asm-prototypes.h: use linux/uaccess.h, not asm/uaccess.h
        riscv: use linux/uaccess.h, not asm/uaccess.h...
        ppc: for put_user() pull linux/uaccess.h, not asm/uaccess.h
      40b9672a
    • Linus Torvalds's avatar
      Merge branch 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs · dc1efc3c
      Linus Torvalds authored
      Pull dcache updates from Al Viro:
       "Neil Brown's d_move()/d_path() race fix"
      
      * 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
        VFS: close race between getcwd() and d_move()
      dc1efc3c
    • Linus Torvalds's avatar
      Merge branch 'akpm' (patches from Andrew) · 73da9e1a
      Linus Torvalds authored
      Merge updates from Andrew Morton:
      
       - misc fixes
      
       - ocfs2 updates
      
       - most of MM
      
      * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
        mm: remove PG_highmem description
        tools, vm: new option to specify kpageflags file
        mm/swap.c: make functions and their kernel-doc agree
        mm, memory_hotplug: fix memmap initialization
        mm: correct comments regarding do_fault_around()
        mm: numa: do not trap faults on shared data section pages.
        hugetlb, mbind: fall back to default policy if vma is NULL
        hugetlb, mempolicy: fix the mbind hugetlb migration
        mm, hugetlb: further simplify hugetlb allocation API
        mm, hugetlb: get rid of surplus page accounting tricks
        mm, hugetlb: do not rely on overcommit limit during migration
        mm, hugetlb: integrate giga hugetlb more naturally to the allocation path
        mm, hugetlb: unify core page allocation accounting and initialization
        mm/memcontrol.c: try harder to decrease [memory,memsw].limit_in_bytes
        mm/memcontrol.c: make local symbol static
        mm/hmm: fix uninitialized use of 'entry' in hmm_vma_walk_pmd()
        include/linux/mmzone.h: fix explanation of lower bits in the SPARSEMEM mem_map pointer
        mm/compaction.c: fix comment for try_to_compact_pages()
        mm/page_ext.c: make page_ext_init a noop when CONFIG_PAGE_EXTENSION but nothing uses it
        zsmalloc: use U suffix for negative literals being shifted
        ...
      73da9e1a
    • Miles Chen's avatar
      mm: remove PG_highmem description · 3f56a2f8
      Miles Chen authored
      Commit cbe37d09 ("[PATCH] mm: remove PG_highmem") removed PG_highmem
      to save a page flag.  So the description of PG_highmem is no longer
      needed.
      
      Link: http://lkml.kernel.org/r/1517391212-2950-1-git-send-email-miles.chen@mediatek.com
      
      
      Signed-off-by: default avatarMiles Chen <miles.chen@mediatek.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3f56a2f8
    • David Rientjes's avatar
      tools, vm: new option to specify kpageflags file · c7905f20
      David Rientjes authored
      page-types currently hardcodes /proc/kpageflags as the file to parse.
      This works when using the tool to examine the state of pageflags on the
      same system, but does not allow storing a snapshot of pageflags at a
      given time to debug issues nor on a different system.
      
      This allows the user to specify a saved version of kpageflags with a new
      page-types -F option.
      
      [akpm@linux-foundation.org: add "filename" to fix usage() string]
      [rientjes@google.com: fix layout]
        Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1801301840050.140969@chino.kir.corp.google.com
      Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1801301458180.153857@chino.kir.corp.google.com
      
      
      Signed-off-by: default avatarDavid Rientjes <rientjes@google.com>
      Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Reviewed-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Konstantin Khlebnikov <koct9i@gmail.com>
      Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c7905f20
    • Randy Dunlap's avatar
      mm/swap.c: make functions and their kernel-doc agree · e02a9f04
      Randy Dunlap authored
      Fix some basic kernel-doc notation in mm/swap.c:
      
       - for function lru_cache_add_anon(), make its kernel-doc function name
         match its function name and change colon to hyphen following the
         function name
      
       - for function pagevec_lookup_entries(), change the function parameter
         name from nr_pages to nr_entries since that is more descriptive of
         what the parameter actually is and then it matches the kernel-doc
         comments also
      
      Fix function kernel-doc to match the change in commit 67fd707f:
      
       - drop the kernel-doc notation for @nr_pages from
         pagevec_lookup_range() and correct the function description for that
         change
      
      Link: http://lkml.kernel.org/r/3b42ee3e-04a9-a6ca-6be4-f00752a114fe@infradead.org
      Fixes: 67fd707f
      
       ("mm: remove nr_pages argument from pagevec_lookup_{,range}_tag()")
      Signed-off-by: default avatarRandy Dunlap <rdunlap@infradead.org>
      Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Cc: Jan Kara <jack@suse.cz>
      Cc: Matthew Wilcox <willy@infradead.org>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Michal Hocko <mhocko@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e02a9f04
    • Michal Hocko's avatar
      mm, memory_hotplug: fix memmap initialization · 9bb5a391
      Michal Hocko authored
      Bharata has noticed that onlining a newly added memory doesn't increase
      the total memory, pointing to commit f7f99100 ("mm: stop zeroing
      memory during allocation in vmemmap") as a culprit.  This commit has
      changed the way how the memory for memmaps is initialized and moves it
      from the allocation time to the initialization time.  This works
      properly for the early memmap init path.
      
      It doesn't work for the memory hotplug though because we need to mark
      page as reserved when the sparsemem section is created and later
      initialize it completely during onlining.  memmap_init_zone is called in
      the early stage of onlining.  With the current code it calls
      __init_single_page and as such it clears up the whole stage and
      therefore online_pages_range skips those pages.
      
      Fix this by skipping mm_zero_struct_page in __init_single_page for
      memory hotplug path.  This is quite uggly but unifying both early init
      and memory hotplug init paths is a large project.  Make sure we plug the
      regression at least.
      
      Link: http://lkml.kernel.org/r/20180130101141.GW21609@dhcp22.suse.cz
      Fixes: f7f99100
      
       ("mm: stop zeroing memory during allocation in vmemmap")
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reported-by: default avatarBharata B Rao <bharata@linux.vnet.ibm.com>
      Tested-by: default avatarBharata B Rao <bharata@linux.vnet.ibm.com>
      Reviewed-by: default avatarPavel Tatashin <pasha.tatashin@oracle.com>
      Cc: Steven Sistare <steven.sistare@oracle.com>
      Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
      Cc: Bob Picco <bob.picco@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>
      9bb5a391
    • William Kucharski's avatar
      mm: correct comments regarding do_fault_around() · da391d64
      William Kucharski authored
      There are multiple comments surrounding do_fault_around that memtion
      fault_around_pages() and fault_around_mask(), two routines that do not
      exist.  These comments should be reworded to reference
      fault_around_bytes, the value which is used to determine how much
      do_fault_around() will attempt to read when processing a fault.
      
      These comments should have been updated when fault_around_pages() and
      fault_around_mask() were removed in commit aecd6f44 ("mm: close race
      between do_fault_around() and fault_around_bytes_set()").
      
      Fixes: aecd6f44 ("mm: close race between do_fault_around() and fault_around_bytes_set()")
      Link: http://lkml.kernel.org/r/302D0B14-C7E9-44C6-8BED-033F9ACBD030@oracle.com
      
      
      Signed-off-by: default avatarWilliam Kucharski <william.kucharski@oracle.com>
      Reviewed-by: default avatarLarry Bassel <larry.bassel@oracle.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      da391d64
    • Henry Willard's avatar
      mm: numa: do not trap faults on shared data section pages. · 859d4adc
      Henry Willard authored
      Workloads consisting of a large number of processes running the same
      program with a very large shared data segment may experience performance
      problems when numa balancing attempts to migrate the shared cow pages.
      This manifests itself with many processes or tasks in
      TASK_UNINTERRUPTIBLE state waiting for the shared pages to be migrated.
      
      The program listed below simulates the conditions with these results
      when run with 288 processes on a 144 core/8 socket machine.
      
      Average throughput 	Average throughput     Average throughput
      with numa_balancing=0	with numa_balancing=1  with numa_balancing=1
           			without the patch      with the patch
      ---------------------	---------------------  ---------------------
      2118782			2021534		       2107979
      
      Complex production environments show less variability and fewer poorly
      performing outliers accompanied with a smaller number of processes
      waiting on NUMA page migration with this patch applied.  In some cases,
      %iowait drops from 16%-26% to 0.
      
        // SPDX-License-Identifier: GPL-2.0
        /*
         * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
         */
        #include <sys/time.h>
        #include <stdio.h>
        #include <wait.h>
        #include <sys/mman.h>
      
        int a[1000000] = {13};
      
        int  main(int argc, const char **argv)
        {
      	int n = 0;
      	int i;
      	pid_t pid;
      	int stat;
      	int *count_array;
      	int cpu_count = 288;
      	long total = 0;
      
      	struct timeval t1, t2 = {(argc > 1 ? atoi(argv[1]) : 10), 0};
      
      	if (argc > 2)
      		cpu_count = atoi(argv[2]);
      
      	count_array = mmap(NULL, cpu_count * sizeof(int),
      			   (PROT_READ|PROT_WRITE),
      			   (MAP_SHARED|MAP_ANONYMOUS), 0, 0);
      
      	if (count_array == MAP_FAILED) {
      		perror("mmap:");
      		return 0;
      	}
      
      	for (i = 0; i < cpu_count; ++i) {
      		pid = fork();
      		if (pid <= 0)
      			break;
      		if ((i & 0xf) == 0)
      			usleep(2);
      	}
      
      	if (pid != 0) {
      		if (i == 0) {
      			perror("fork:");
      			return 0;
      		}
      
      		for (;;) {
      			pid = wait(&stat);
      			if (pid < 0)
      				break;
      		}
      
      		for (i = 0; i < cpu_count; ++i)
      			total += count_array[i];
      
      		printf("Total %ld\n", total);
      		munmap(count_array, cpu_count * sizeof(int));
      		return 0;
      	}
      
      	gettimeofday(&t1, 0);
      	timeradd(&t1, &t2, &t1);
      	while (timercmp(&t2, &t1, <)) {
      		int b = 0;
      		int j;
      
      		for (j = 0; j < 1000000; j++)
      			b += a[j];
      		gettimeofday(&t2, 0);
      		n++;
      	}
      	count_array[i] = n;
      	return 0;
        }
      
      This patch changes change_pte_range() to skip shared copy-on-write pages
      when called from change_prot_numa().
      
      NOTE: change_prot_numa() is nominally called from task_numa_work() and
      queue_pages_test_walk().  task_numa_work() is the auto NUMA balancing
      path, and queue_pages_test_walk() is part of explicit NUMA policy
      management.  However, queue_pages_test_walk() only calls
      change_prot_numa() when MPOL_MF_LAZY is specified and currently that is
      not allowed, so change_prot_numa() is only called from auto NUMA
      balancing.
      
      In the case of explicit NUMA policy management, shared pages are not
      migrated unless MPOL_MF_MOVE_ALL is specified, and MPOL_MF_MOVE_ALL
      depends on CAP_SYS_NICE.  Currently, there is no way to pass information
      about MPOL_MF_MOVE_ALL to change_pte_range.  This will have to be fixed
      if MPOL_MF_LAZY is enabled and MPOL_MF_MOVE_ALL is to be honored in lazy
      migration mode.
      
      task_numa_work() skips the read-only VMAs of programs and shared
      libraries.
      
      Link: http://lkml.kernel.org/r/1516751617-7369-1-git-send-email-henry.willard@oracle.com
      
      
      Signed-off-by: default avatarHenry Willard <henry.willard@oracle.com>
      Reviewed-by: default avatarHåkon Bugge <haakon.bugge@oracle.com>
      Reviewed-by: default avatarSteve Sistare <steven.sistare@oracle.com>
      Acked-by: default avatarMel Gorman <mgorman@suse.de>
      Cc: Kate Stewart <kstewart@linuxfoundation.org>
      Cc: Zi Yan <zi.yan@cs.rutgers.edu>
      Cc: Philippe Ombredanne <pombredanne@nexb.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: "Jérôme Glisse" <jglisse@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      859d4adc
    • Michal Hocko's avatar
      hugetlb, mbind: fall back to default policy if vma is NULL · 389c8178
      Michal Hocko authored
      Dan Carpenter has noticed that mbind migration callback (new_page) can
      get a NULL vma pointer and choke on it inside alloc_huge_page_vma which
      relies on the VMA to get the hstate.  We used to BUG_ON this case but
      the BUG_+ON has been removed recently by "hugetlb, mempolicy: fix the
      mbind hugetlb migration".
      
      The proper way to handle this is to get the hstate from the migrated
      page and rely on huge_node (resp.  get_vma_policy) do the right thing
      with null VMA.  We are currently falling back to the default mempolicy
      in that case which is in line what THP path is doing here.
      
      Link: http://lkml.kernel.org/r/20180110104712.GR1732@dhcp22.suse.cz
      
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Mike Kravetz <mike.kravetz@oracle.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      389c8178
    • Michal Hocko's avatar
      hugetlb, mempolicy: fix the mbind hugetlb migration · ebd63723
      Michal Hocko authored
      do_mbind migration code relies on alloc_huge_page_noerr for hugetlb
      pages.  alloc_huge_page_noerr uses alloc_huge_page which is a highlevel
      allocation function which has to take care of reserves, overcommit or
      hugetlb cgroup accounting.  None of that is really required for the page
      migration because the new page is only temporal and either will replace
      the original page or it will be dropped.  This is essentially as for
      other migration call paths and there shouldn't be any reason to handle
      mbind in a special way.
      
      The current implementation is even suboptimal because the migration
      might fail just because the hugetlb cgroup limit is reached, or the
      overcommit is saturated.
      
      Fix this by making mbind like other hugetlb migration paths.  Add a new
      migration helper alloc_huge_page_vma as a wrapper around
      alloc_huge_page_nodemask with additional mempolicy handling.
      
      alloc_huge_page_noerr has no more users and it can go.
      
      Link: http://lkml.kernel.org/r/20180103093213.26329-7-mhocko@kernel.org
      
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
      Reviewed-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Andrea Reale <ar@linux.vnet.ibm.com>
      Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Zi Yan <zi.yan@cs.rutgers.edu>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ebd63723
    • Michal Hocko's avatar
      mm, hugetlb: further simplify hugetlb allocation API · 0c397dae
      Michal Hocko authored
      Hugetlb allocator has several layer of allocation functions depending
      and the purpose of the allocation.  There are two allocators depending
      on whether the page can be allocated from the page allocator or we need
      a contiguous allocator.  This is currently opencoded in
      alloc_fresh_huge_page which is the only path that might allocate giga
      pages which require the later allocator.  Create alloc_fresh_huge_page
      which hides this implementation detail and use it in all callers which
      hardcoded the buddy allocator path (__hugetlb_alloc_buddy_huge_page).
      This shouldn't introduce any funtional change because both migration and
      surplus allocators exlude giga pages explicitly.
      
      While we are at it let's do some renaming.  The current scheme is not
      consistent and overly painfull to read and understand.  Get rid of
      prefix underscores from most functions.  There is no real reason to make
      names longer.
      
      * alloc_fresh_huge_page is the new layer to abstract underlying
        allocator
      * __hugetlb_alloc_buddy_huge_page becomes shorter and neater
        alloc_buddy_huge_page.
      * Former alloc_fresh_huge_page becomes alloc_pool_huge_page because we put
        the new page directly to the pool
      * alloc_surplus_huge_page can drop the opencoded prep_new_huge_page code
        as it uses alloc_fresh_huge_page now
      * others lose their excessive prefix underscores to make names shorter
      
      [dan.carpenter@oracle.com: fix double unlock bug in alloc_surplus_huge_page()]
        Link: http://lkml.kernel.org/r/20180109200559.g3iz5kvbdrz7yydp@mwanda
      Link: http://lkml.kernel.org/r/20180103093213.26329-6-mhocko@kernel.org
      
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
      Reviewed-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Andrea Reale <ar@linux.vnet.ibm.com>
      Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Zi Yan <zi.yan@cs.rutgers.edu>
      Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      0c397dae
    • Michal Hocko's avatar
      mm, hugetlb: get rid of surplus page accounting tricks · 9980d744
      Michal Hocko authored
      alloc_surplus_huge_page increases the pool size and the number of
      surplus pages opportunistically to prevent from races with the pool size
      change.  See commit d1c3fb1f ("hugetlb: introduce
      nr_overcommit_hugepages sysctl") for more details.
      
      The resulting code is unnecessarily hairy, cause code duplication and
      doesn't allow to share the allocation paths.  Moreover pool size changes
      tend to be very seldom so optimizing for them is not really reasonable.
      Simplify the code and allow to allocate a fresh surplus page as long as
      we are under the overcommit limit and then recheck the condition after
      the allocation and drop the new page if the situation has changed.  This
      should provide a reasonable guarantee that an abrupt allocation requests
      will not go way off the limit.
      
      If we consider races with the pool shrinking and enlarging then we
      should be reasonably safe as well.  In the first case we are off by one
      in the worst case and the second case should work OK because the page is
      not yet visible.  We can waste CPU cycles for the allocation but that
      should be acceptable for a relatively rare condition.
      
      Link: http://lkml.kernel.org/r/20180103093213.26329-5-mhocko@kernel.org
      
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
      Reviewed-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Andrea Reale <ar@linux.vnet.ibm.com>
      Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Zi Yan <zi.yan@cs.rutgers.edu>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9980d744
    • Michal Hocko's avatar
      mm, hugetlb: do not rely on overcommit limit during migration · ab5ac90a
      Michal Hocko authored
      hugepage migration relies on __alloc_buddy_huge_page to get a new page.
      This has 2 main disadvantages.
      
      1) it doesn't allow to migrate any huge page if the pool is used
         completely which is not an exceptional case as the pool is static and
         unused memory is just wasted.
      
      2) it leads to a weird semantic when migration between two numa nodes
         might increase the pool size of the destination NUMA node while the
         page is in use.  The issue is caused by per NUMA node surplus pages
         tracking (see free_huge_page).
      
      Address both issues by changing the way how we allocate and account
      pages allocated for migration.  Those should temporal by definition.  So
      we mark them that way (we will abuse page flags in the 3rd page) and
      update free_huge_page to free such pages to the page allocator.  Page
      migration path then just transfers the temporal status from the new page
      to the old one which will be freed on the last reference.  The global
      surplus count will never change during this path but we still have to be
      careful when migrating a per-node suprlus page.  This is now handled in
      move_hugetlb_state which is called from the migration path and it copies
      the hugetlb specific page state and fixes up the accounting when needed
      
      Rename __alloc_buddy_huge_page to __alloc_surplus_huge_page to better
      reflect its purpose.  The new allocation routine for the migration path
      is __alloc_migrate_huge_page.
      
      The user visible effect of this patch is that migrated pages are really
      temporal and they travel between NUMA nodes as per the migration
      request:
      
      Before migration
        /sys/devices/system/node/node0/hugepages/hugepages-2048kB/free_hugepages:0
        /sys/devices/system/node/node0/hugepages/hugepages-2048kB/nr_hugepages:1
        /sys/devices/system/node/node0/hugepages/hugepages-2048kB/surplus_hugepages:0
        /sys/devices/system/node/node1/hugepages/hugepages-2048kB/free_hugepages:0
        /sys/devices/system/node/node1/hugepages/hugepages-2048kB/nr_hugepages:0
        /sys/devices/system/node/node1/hugepages/hugepages-2048kB/surplus_hugepages:0
      
      After
        /sys/devices/system/node/node0/hugepages/hugepages-2048kB/free_hugepages:0
        /sys/devices/system/node/node0/hugepages/hugepages-2048kB/nr_hugepages:0
        /sys/devices/system/node/node0/hugepages/hugepages-2048kB/surplus_hugepages:0
        /sys/devices/system/node/node1/hugepages/hugepages-2048kB/free_hugepages:0
        /sys/devices/system/node/node1/hugepages/hugepages-2048kB/nr_hugepages:1
        /sys/devices/system/node/node1/hugepages/hugepages-2048kB/surplus_hugepages:0
      
      with the previous implementation, both nodes would have nr_hugepages:1
      until the page is freed.
      
      Link: http://lkml.kernel.org/r/20180103093213.26329-4-mhocko@kernel.org
      
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
      Reviewed-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Andrea Reale <ar@linux.vnet.ibm.com>
      Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Zi Yan <zi.yan@cs.rutgers.edu>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ab5ac90a
    • Michal Hocko's avatar
      mm, hugetlb: integrate giga hugetlb more naturally to the allocation path · d9cc948f
      Michal Hocko authored
      Gigantic hugetlb pages were ingrown to the hugetlb code as an alien
      specie with a lot of special casing.  The allocation path is not an
      exception.  Unnecessarily so to be honest.  It is true that the
      underlying allocator is different but that is an implementation detail.
      
      This patch unifies the hugetlb allocation path that a prepares fresh
      pool pages.  alloc_fresh_gigantic_page basically copies
      alloc_fresh_huge_page logic so we can move everything there.  This will
      simplify set_max_huge_pages which doesn't have to care about what kind
      of huge page we allocate.
      
      Link: http://lkml.kernel.org/r/20180103093213.26329-3-mhocko@kernel.org
      
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
      Reviewed-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Andrea Reale <ar@linux.vnet.ibm.com>
      Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Zi Yan <zi.yan@cs.rutgers.edu>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d9cc948f
    • Michal Hocko's avatar
      mm, hugetlb: unify core page allocation accounting and initialization · af0fb9df
      Michal Hocko authored
      Patch series "mm, hugetlb: allocation API and migration improvements"
      
      Motivation:
      
      this is a follow up for [3] for the allocation API and [4] for the
      hugetlb migration.  It wasn't really easy to split those into two
      separate patch series as they share some code.
      
      My primary motivation to touch this code is to make the gigantic pages
      migration working.  The giga pages allocation code is just too fragile
      and hacked into the hugetlb code now.  This series tries to move giga
      pages closer to the first class citizen.  We are not there yet but
      having 5 patches is quite a lot already and it will already make the
      code much easier to follow.  I will come with other changes on top after
      this sees some review.
      
      The first two patches should be trivial to review.  The third patch
      changes the way how we migrate huge pages.  Newly allocated pages are a
      subject of the overcommit check and they participate surplus accounting
      which is quite unfortunate as the changelog explains.  This patch
      doesn't change anything wrt.  giga pages.
      
      Patch #4 removes the surplus accounting hack from
      __alloc_surplus_huge_page.  I hope I didn't miss anything there and a
      deeper review is really due there.
      
      Patch #5 finally unifies allocation paths and giga pages shouldn't be
      any special anymore.  There is also some renaming going on as well.
      
      This patch (of 6):
      
      hugetlb allocator has two entry points to the page allocator
       - alloc_fresh_huge_page_node
       - __hugetlb_alloc_buddy_huge_page
      
      The two differ very subtly in two aspects.  The first one doesn't care
      about HTLB_BUDDY_* stats and it doesn't initialize the huge page.
      prep_new_huge_page is not used because it not only initializes hugetlb
      specific stuff but because it also put_page and releases the page to the
      hugetlb pool which is not what is required in some contexts.  This makes
      things more complicated than necessary.
      
      Simplify things by a) removing the page allocator entry point duplicity
      and only keep __hugetlb_alloc_buddy_huge_page and b) make
      prep_new_huge_page more reusable by removing the put_page which moves
      the page to the allocator pool.  All current callers are updated to call
      put_page explicitly.  Later patches will add new callers which won't
      need it.
      
      This patch shouldn't introduce any functional change.
      
      Link: http://lkml.kernel.org/r/20180103093213.26329-2-mhocko@kernel.org
      
      
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
      Reviewed-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Andrea Reale <ar@linux.vnet.ibm.com>
      Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Zi Yan <zi.yan@cs.rutgers.edu>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      af0fb9df
    • Andrey Ryabinin's avatar
      mm/memcontrol.c: try harder to decrease [memory,memsw].limit_in_bytes · 1ab5c056
      Andrey Ryabinin authored
      mem_cgroup_resize_[memsw]_limit() tries to free only 32
      (SWAP_CLUSTER_MAX) pages on each iteration.  This makes it practically
      impossible to decrease limit of memory cgroup.  Tasks could easily
      allocate back 32 pages, so we can't reduce memory usage, and once
      retry_count reaches zero we return -EBUSY.
      
      Easy to reproduce the problem by running the following commands:
      
        mkdir /sys/fs/cgroup/memory/test
        echo $$ >> /sys/fs/cgroup/memory/test/tasks
        cat big_file > /dev/null &
        sleep 1 && echo $((100*1024*1024)) > /sys/fs/cgroup/memory/test/memory.limit_in_bytes
        -bash: echo: write error: Device or resource busy
      
      Instead of relying on retry_count, keep retrying the reclaim until the
      desired limit is reached or fail if the reclaim doesn't make any
      progress or a signal is pending.
      
      Link: http://lkml.kernel.org/r/20180119132544.19569-1-aryabinin@virtuozzo.com
      
      
      Signed-off-by: default avatarAndrey Ryabinin <aryabinin@virtuozzo.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Cc: Shakeel Butt <shakeelb@google.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1ab5c056
    • Christopher Díaz Riveros's avatar
      mm/memcontrol.c: make local symbol static · 8ad6e404
      Christopher Díaz Riveros authored
      Fix the following sparse warning:
      
        mm/memcontrol.c:1097:14: warning: symbol 'memcg1_stats' was not declared. Should it be static?
      
      Link: http://lkml.kernel.org/r/20180118193327.14200-1-chrisadr@gentoo.org
      
      
      Signed-off-by: default avatarChristopher Díaz Riveros <chrisadr@gentoo.org>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8ad6e404
    • Ralph Campbell's avatar
      mm/hmm: fix uninitialized use of 'entry' in hmm_vma_walk_pmd() · 8d63e4cd
      Ralph Campbell authored
      The variable 'entry' is used before being initialized in
      hmm_vma_walk_pmd().
      
      No bad effect (beside performance hit) so !non_swap_entry(0) evaluate to
      true which trigger a fault as if CPU was trying to access migrated
      memory and migrate memory back from device memory to regular memory.
      
      This function (hmm_vma_walk_pmd()) is called when a device driver tries
      to populate its own page table.  For migrated memory it should not
      happen as the device driver should already have populated its page table
      correctly during the migration.
      
      Only case I can think of is multi-GPU where a second GPU triggers
      migration back to regular memory.  Again this would just result in a
      performance hit, nothing bad would happen.
      
      Link: http://lkml.kernel.org/r/20180122185759.26286-1-jglisse@redhat.com
      
      
      Signed-off-by: default avatarRalph Campbell <rcampbell@nvidia.com>
      Signed-off-by: default avatarJérôme Glisse <jglisse@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8d63e4cd