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  1. Jul 13, 2019
  3. Jul 12, 2019
    • Linus Torvalds's avatar
      Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 753c8d9b
      Linus Torvalds authored 
      Pull x86 fixes from Thomas Gleixner:
 "A collection of assorted fixes:

   - Fix for the pinned cr0/4 fallout which escaped all testing efforts
     because the kvm-intel module was never loaded when the kernel was
     compiled with CONFIG_PARAVIRT=n. The cr0/4 accessors are moved out
     of line and static key is now solely used in the core code and
     therefore can stay in the RO after init section. So the kvm-intel
     and other modules do not longer reference the (read only) static
     key which the module loader tried to update.

   - Prevent an infinite loop in arch_stack_walk_user() by breaking out
     of the loop once the return address is detected to be 0.

   - Prevent the int3_emulate_call() selftest from corrupting the stack
     when KASAN is enabled. KASASN clobbers more registers than covered
     by the emulated call implementation. Convert the int3_magic()
     selftest to a ASM function so the compiler cannot KASANify it.

   - Unbreak the build with old GCC versions and with the Gold linker by
     reverting the 'Move of _etext to the actual end of .text'. In both
     cases the build fails with 'Invalid absolute R_X86_64_32S
     relocation: _etext'

   - Initialize the context lock for init_mm, which was never an issue
     until the alternatives code started to use a temporary mm for
     patching.

   - Fix a build warning vs. the LOWMEM_PAGES constant where clang
     complains rightfully about a signed integer overflow in the shift
     operation by converting the operand to an ULL.

   - Adjust the misnamed ENDPROC() of common_spurious in the 32bit entry
     code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/stacktrace: Prevent infinite loop in arch_stack_walk_user()
  x86/asm: Move native_write_cr0/4() out of line
  x86/pgtable/32: Fix LOWMEM_PAGES constant
  x86/alternatives: Fix int3_emulate_call() selftest stack corruption
  x86/entry/32: Fix ENDPROC of common_spurious
  Revert "x86/build: Move _etext to actual end of .text"
  x86/ldt: Initialize the context lock for init_mm
      753c8d9b
    • Linus Torvalds's avatar
      Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · d7fe42a6
      Linus Torvalds authored 
      Pull timer fixes from Thomas Gleixner:
 "Two small fixes from the timer departement:

   - Prevent the compiler from converting the nanoseconds adjustment
     loop in the VDSO update function to a division (__udivdi3) by using
     the __iter_div_u64_rem() inline function which exists to prevent
     exactly that problem.

   - Fix the wrong argument order of the GENMASK macro in the NPCM timer
     driver"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping/vsyscall: Use __iter_div_u64_rem()
  clocksource/drivers/npcm: Fix misuse of GENMASK macro
      d7fe42a6
    • Linus Torvalds's avatar
      Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 02150fab
      Linus Torvalds authored 
      Pull stacktrace fix from Thomas Gleixner:
 "Fix yet another instance of kernel thread check which ignores that
  kernel threads can call use_mm()"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  stacktrace: Use PF_KTHREAD to check for kernel threads
      02150fab
    • Linus Torvalds's avatar
      Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 3a83f575
      Linus Torvalds authored 
      Pull irq fixes from Thomas Gleixner:
 "Two small fixes for interrupt chip drivers:

   - Prevent UAF in the new RZA1 chip driver

   - Fix the wrong argument order of the GENMASK macro in the GIC code"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Fix misuse of GENMASK macro
  irqchip/renesas-rza1: Prevent use-after-free in rza1_irqc_probe()
      3a83f575
    • Linus Torvalds's avatar
      Merge tag 'acpi-5.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm · a131c2bf
      Linus Torvalds authored 
      Pull ACPI fix from Rafael Wysocki:
 "Revert a recent ACPICA commit causing systems to hang at boot time"

* tag 'acpi-5.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  Revert "ACPICA: Update table load object initialization"
      a131c2bf
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next · 237f83df
      Linus Torvalds authored 
      Pull networking updates from David Miller:
 "Some highlights from this development cycle:

   1) Big refactoring of ipv6 route and neigh handling to support
      nexthop objects configurable as units from userspace. From David
      Ahern.

   2) Convert explored_states in BPF verifier into a hash table,
      significantly decreased state held for programs with bpf2bpf
      calls, from Alexei Starovoitov.

   3) Implement bpf_send_signal() helper, from Yonghong Song.

   4) Various classifier enhancements to mvpp2 driver, from Maxime
      Chevallier.

   5) Add aRFS support to hns3 driver, from Jian Shen.

   6) Fix use after free in inet frags by allocating fqdirs dynamically
      and reworking how rhashtable dismantle occurs, from Eric Dumazet.

   7) Add act_ctinfo packet classifier action, from Kevin
      Darbyshire-Bryant.

   8) Add TFO key backup infrastructure, from Jason Baron.

   9) Remove several old and unused ISDN drivers, from Arnd Bergmann.

  10) Add devlink notifications for flash update status to mlxsw driver,
      from Jiri Pirko.

  11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.

  12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.

  13) Various enhancements to ipv6 flow label handling, from Eric
      Dumazet and Willem de Bruijn.

  14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
      der Merwe, and others.

  15) Various improvements to axienet driver including converting it to
      phylink, from Robert Hancock.

  16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.

  17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
      Radulescu.

  18) Add devlink health reporting to mlx5, from Moshe Shemesh.

  19) Convert stmmac over to phylink, from Jose Abreu.

  20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
      Shalom Toledo.

  21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.

  22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.

  23) Track spill/fill of constants in BPF verifier, from Alexei
      Starovoitov.

  24) Support bounded loops in BPF, from Alexei Starovoitov.

  25) Various page_pool API fixes and improvements, from Jesper Dangaard
      Brouer.

  26) Just like ipv4, support ref-countless ipv6 route handling. From
      Wei Wang.

  27) Support VLAN offloading in aquantia driver, from Igor Russkikh.

  28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.

  29) Add flower GRE encap/decap support to nfp driver, from Pieter
      Jansen van Vuuren.

  30) Protect against stack overflow when using act_mirred, from John
      Hurley.

  31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.

  32) Use page_pool API in netsec driver, Ilias Apalodimas.

  33) Add Google gve network driver, from Catherine Sullivan.

  34) More indirect call avoidance, from Paolo Abeni.

  35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.

  36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.

  37) Add MPLS manipulation actions to TC, from John Hurley.

  38) Add sending a packet to connection tracking from TC actions, and
      then allow flower classifier matching on conntrack state. From
      Paul Blakey.

  39) Netfilter hw offload support, from Pablo Neira Ayuso"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
  net/mlx5e: Return in default case statement in tx_post_resync_params
  mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
  net: dsa: add support for BRIDGE_MROUTER attribute
  pkt_sched: Include const.h
  net: netsec: remove static declaration for netsec_set_tx_de()
  net: netsec: remove superfluous if statement
  netfilter: nf_tables: add hardware offload support
  net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
  net: flow_offload: add flow_block_cb_is_busy() and use it
  net: sched: remove tcf block API
  drivers: net: use flow block API
  net: sched: use flow block API
  net: flow_offload: add flow_block_cb_{priv, incref, decref}()
  net: flow_offload: add list handling functions
  net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
  net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
  net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
  net: flow_offload: add flow_block_cb_setup_simple()
  net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
  net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
  ...
      237f83df
    • Linus Torvalds's avatar
      Merge tag 'clone3-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux · 8f6ccf61
      Linus Torvalds authored 
      Pull clone3 system call from Christian Brauner:
 "This adds the clone3 syscall which is an extensible successor to clone
  after we snagged the last flag with CLONE_PIDFD during the 5.2 merge
  window for clone(). It cleanly supports all of the flags from clone()
  and thus all legacy workloads.

  There are few user visible differences between clone3 and clone.
  First, CLONE_DETACHED will cause EINVAL with clone3 so we can reuse
  this flag. Second, the CSIGNAL flag is deprecated and will cause
  EINVAL to be reported. It is superseeded by a dedicated "exit_signal"
  argument in struct clone_args thus freeing up even more flags. And
  third, clone3 gives CLONE_PIDFD a dedicated return argument in struct
  clone_args instead of abusing CLONE_PARENT_SETTID's parent_tidptr
  argument.

  The clone3 uapi is designed to be easy to handle on 32- and 64 bit:

    /* uapi */
    struct clone_args {
            __aligned_u64 flags;
            __aligned_u64 pidfd;
            __aligned_u64 child_tid;
            __aligned_u64 parent_tid;
            __aligned_u64 exit_signal;
            __aligned_u64 stack;
            __aligned_u64 stack_size;
            __aligned_u64 tls;
    };

  and a separate kernel struct is used that uses proper kernel typing:

    /* kernel internal */
    struct kernel_clone_args {
            u64 flags;
            int __user *pidfd;
            int __user *child_tid;
            int __user *parent_tid;
            int exit_signal;
            unsigned long stack;
            unsigned long stack_size;
            unsigned long tls;
    };

  The system call comes with a size argument which enables the kernel to
  detect what version of clone_args userspace is passing in. clone3
  validates that any additional bytes a given kernel does not know about
  are set to zero and that the size never exceeds a page.

  A nice feature is that this patchset allowed us to cleanup and
  simplify various core kernel codepaths in kernel/fork.c by making the
  internal _do_fork() function take struct kernel_clone_args even for
  legacy clone().

  This patch also unblocks the time namespace patchset which wants to
  introduce a new CLONE_TIMENS flag.

  Note, that clone3 has only been wired up for x86{_32,64}, arm{64}, and
  xtensa. These were the architectures that did not require special
  massaging.

  Other architectures treat fork-like system calls individually and
  after some back and forth neither Arnd nor I felt confident that we
  dared to add clone3 unconditionally to all architectures. We agreed to
  leave this up to individual architecture maintainers. This is why
  there's an additional patch that introduces __ARCH_WANT_SYS_CLONE3
  which any architecture can set once it has implemented support for
  clone3. The patch also adds a cond_syscall(clone3) for architectures
  such as nios2 or h8300 that generate their syscall table by simply
  including asm-generic/unistd.h. The hope is to get rid of
  __ARCH_WANT_SYS_CLONE3 and cond_syscall() rather soon"

* tag 'clone3-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  arch: handle arches who do not yet define clone3
  arch: wire-up clone3() syscall
  fork: add clone3
      8f6ccf61
  5. Jul 11, 2019
    • Eiichi Tsukata's avatar
      x86/stacktrace: Prevent infinite loop in arch_stack_walk_user() · cbf5b73d
      Eiichi Tsukata authored 
      arch_stack_walk_user() checks `if (fp == frame.next_fp)` to prevent a
infinite loop by self reference but it's not enogh for circular reference.

Once a lack of return address is found, there is no point to continue the
loop, so break out.

Fixes: 02b67518

 ("tracing: add support for userspace stacktraces in tracing/iter_ctrl")
Signed-off-by: default avatarEiichi Tsukata <devel@etsukata.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20190711023501.963-1-devel@etsukata.com
      cbf5b73d
    • Linus Torvalds's avatar
      Merge tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux · 5450e8a3
      Linus Torvalds authored 
      Pull pidfd updates from Christian Brauner:
 "This adds two main features.

   - First, it adds polling support for pidfds. This allows process
     managers to know when a (non-parent) process dies in a race-free
     way.

     The notification mechanism used follows the same logic that is
     currently used when the parent of a task is notified of a child's
     death. With this patchset it is possible to put pidfds in an
     {e}poll loop and get reliable notifications for process (i.e.
     thread-group) exit.

   - The second feature compliments the first one by making it possible
     to retrieve pollable pidfds for processes that were not created
     using CLONE_PIDFD.

     A lot of processes get created with traditional PID-based calls
     such as fork() or clone() (without CLONE_PIDFD). For these
     processes a caller can currently not create a pollable pidfd. This
     is a problem for Android's low memory killer (LMK) and service
     managers such as systemd.

  Both patchsets are accompanied by selftests.

  It's perhaps worth noting that the work done so far and the work done
  in this branch for pidfd_open() and polling support do already see
  some adoption:

   - Android is in the process of backporting this work to all their LTS
     kernels [1]

   - Service managers make use of pidfd_send_signal but will need to
     wait until we enable waiting on pidfds for full adoption.

   - And projects I maintain make use of both pidfd_send_signal and
     CLONE_PIDFD [2] and will use polling support and pidfd_open() too"

[1] https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.9+backport%22
    https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.14+backport%22
    https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.19+backport%22

[2] https://github.com/lxc/lxc/blob/aab6e3eb73c343231cdde775db938994fc6f2803/src/lxc/start.c#L1753

* tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  tests: add pidfd_open() tests
  arch: wire-up pidfd_open()
  pid: add pidfd_open()
  pidfd: add polling selftests
  pidfd: add polling support
      5450e8a3
    • Linus Torvalds's avatar
      Merge tag 'm68k-for-v5.3-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k · 29cd581b
      Linus Torvalds authored 
      Pull m68k fix from Geert Uytterhoeven:
 "Don't select ARCH_HAS_DMA_PREP_COHERENT for nommu or coldfire.

  This is a fix for an issue detected in next, to avoid introducing
  build failures when merging Christoph's dma-mapping tree later"

* tag 'm68k-for-v5.3-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k: Don't select ARCH_HAS_DMA_PREP_COHERENT for nommu or coldfire
      29cd581b
    • Linus Torvalds's avatar
      Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu · 398364a3
      Linus Torvalds authored 
      Pull m68nommu updates from Greg Ungerer:
 "A series of cleanups for the FLAT format binary loader, binfmt_flat,
  from Christoph.

  The end goal is to support no-MMU on RISC-V, and the last patch
  enables that"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  riscv: add binfmt_flat support
  binfmt_flat: don't offset the data start
  binfmt_flat: move the MAX_SHARED_LIBS definition to binfmt_flat.c
  binfmt_flat: remove the persistent argument from flat_get_addr_from_rp
  binfmt_flat: provide an asm-generic/flat.h
  binfmt_flat: make support for old format binaries optional
  binfmt_flat: add a ARCH_HAS_BINFMT_FLAT option
  binfmt_flat: add endianess annotations
  binfmt_flat: use fixed size type for the on-disk format
  binfmt_flat: consolidate two version of flat_v2_reloc_t
  binfmt_flat: remove the unused OLD_FLAT_FLAG_RAM definition
  binfmt_flat: remove the uapi <linux/flat.h> header
  binfmt_flat: replace flat_argvp_envp_on_stack with a Kconfig variable
  binfmt_flat: remove flat_old_ram_flag
  binfmt_flat: provide a default version of flat_get_relocate_addr
  binfmt_flat: remove flat_set_persistent
  binfmt_flat: remove flat_reloc_valid
      398364a3
    • Linus Torvalds's avatar
      Merge tag 'nfsd-5.3' of git://linux-nfs.org/~bfields/linux · d2b6b4c8
      Linus Torvalds authored 
      Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Add a new /proc/fs/nfsd/clients/ directory which exposes some
     long-requested information about NFSv4 clients (like open files)
     and allows forced revocation of client state.

   - Replace the global duplicate reply cache by a cache per network
     namespace; previously, a request in one network namespace could
     incorrectly match an entry from another, though we haven't seen
     this in production. This is the last remaining container bug that
     I'm aware of; at this point you should be able to run separate
     nfsd's in each network namespace, each with their own set of
     exports, and everything should work.

   - Cleanup and modify lock code to show the pid of lockd as the owner
     of NLM locks. This is the correct version of the bugfix originally
     attempted in b8eee0e9 ("lockd: Show pid of lockd for remote
     locks")"

* tag 'nfsd-5.3' of git://linux-nfs.org/~bfields/linux: (34 commits)
  nfsd: Make __get_nfsdfs_client() static
  nfsd: Make two functions static
  nfsd: Fix misuse of strlcpy
  sunrpc/cache: remove the exporting of cache_seq_next
  nfsd: decode implementation id
  nfsd: create xdr_netobj_dup helper
  nfsd: allow forced expiration of NFSv4 clients
  nfsd: create get_nfsdfs_clp helper
  nfsd4: show layout stateids
  nfsd: show lock and deleg stateids
  nfsd4: add file to display list of client's opens
  nfsd: add more information to client info file
  nfsd: escape high characters in binary data
  nfsd: copy client's address including port number to cl_addr
  nfsd4: add a client info file
  nfsd: make client/ directory names small ints
  nfsd: add nfsd/clients directory
  nfsd4: use reference count to free client
  nfsd: rename cl_refcount
  nfsd: persist nfsd filesystem across mounts
  ...
      d2b6b4c8
    • Linus Torvalds's avatar
      Merge tag 'gfs2-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 · 0248a8be
      Linus Torvalds authored 
      Pull gfs2 updates from Andreas Gruenbacher:
 "Some relatively minor changes for gfs2:

   - An initial batch of obvious cleanups and fixes from Bob's recovery
     patch queue.

   - Two iomap conversion patches and some cleanups from Christoph
     Hellwig.

   - A cosmetic cleanup from Kefeng Wang (Huawei).

   - Another minor fix and cleanup by me"

* tag 'gfs2-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Remove unused gfs2_iomap_alloc argument
  gfs2: don't use buffer_heads in gfs2_allocate_page_backing
  gfs2: use iomap_bmap instead of generic_block_bmap
  gfs2: mark stuffed_readpage static
  gfs2: merge gfs2_writepage_common into gfs2_writepage
  gfs2: merge gfs2_writeback_aops and gfs2_ordered_aops
  gfs2: remove the unused gfs2_stuffed_write_end function
  gfs2: use page_offset in gfs2_page_mkwrite
  gfs2: replace more printk with calls to fs_info and friends
  gfs2: dump fsid when dumping glock problems
  gfs2: simplify gfs2_freeze by removing case
  gfs2: Rename SDF_SHUTDOWN to SDF_WITHDRAWN
  gfs2: Warn when a journal replay overwrites a rgrp with buffers
  gfs2: log which portion of the journal is replayed
  gfs2: eliminate tr_num_revoke_rm
  gfs2: kthread and remount improvements
  gfs2: Use IS_ERR_OR_NULL
  gfs2: Clean up freeing struct gfs2_sbd
      0248a8be
    • Linus Torvalds's avatar
      Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 · 2e756758
      Linus Torvalds authored 
      Pull ext4 updates from Ted Ts'o:
 "Many bug fixes and cleanups, and an optimization for case-insensitive
  lookups"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix coverity warning on error path of filename setup
  ext4: replace ktype default_attrs with default_groups
  ext4: rename htree_inline_dir_to_tree() to ext4_inlinedir_to_tree()
  ext4: refactor initialize_dirent_tail()
  ext4: rename "dirent_csum" functions to use "dirblock"
  ext4: allow directory holes
  jbd2: drop declaration of journal_sync_buffer()
  ext4: use jbd2_inode dirty range scoping
  jbd2: introduce jbd2_inode dirty range scoping
  mm: add filemap_fdatawait_range_keep_errors()
  ext4: remove redundant assignment to node
  ext4: optimize case-insensitive lookups
  ext4: make __ext4_get_inode_loc plug
  ext4: clean up kerneldoc warnigns when building with W=1
  ext4: only set project inherit bit for directory
  ext4: enforce the immutable flag on open files
  ext4: don't allow any modifications to an immutable file
  jbd2: fix typo in comment of journal_submit_inode_data_buffers
  jbd2: fix some print format mistakes
  ext4: gracefully handle ext4_break_layouts() failure during truncate
      2e756758
    • Linus Torvalds's avatar
      Merge tag 'afs-next-20190628' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs · 8dda9957
      Linus Torvalds authored 
      Pull afs updates from David Howells:
 "A set of minor changes for AFS:

   - Remove an unnecessary check in afs_unlink()

   - Add a tracepoint for tracking callback management

   - Add a tracepoint for afs_server object usage

   - Use struct_size()

   - Add mappings for AFS UAE abort codes to Linux error codes, using
     symbolic names rather than hex numbers in the .c file"

* tag 'afs-next-20190628' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Add support for the UAE error table
  fs/afs: use struct_size() in kzalloc()
  afs: Trace afs_server usage
  afs: Add some callback management tracepoints
  afs: afs_unlink() doesn't need to check dentry->d_inode
      8dda9957