1. 26 5月, 2016 16 次提交
    • I
      libceph: move schedule_delayed_work() in ceph_osdc_init() · b37ee1b9
      Ilya Dryomov 提交于
      ceph_osdc_stop() isn't called if ceph_osdc_init() fails, so we end up
      with handle_osds_timeout() running on invalid memory if any one of the
      allocations fails.  Call schedule_delayed_work() after everything is
      setup, just before returning.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      b37ee1b9
    • I
      libceph: redo callbacks and factor out MOSDOpReply decoding · fe5da05e
      Ilya Dryomov 提交于
      If you specify ACK | ONDISK and set ->r_unsafe_callback, both
      ->r_callback and ->r_unsafe_callback(true) are called on ack.  This is
      very confusing.  Redo this so that only one of them is called:
      
          ->r_unsafe_callback(true), on ack
          ->r_unsafe_callback(false), on commit
      
      or
      
          ->r_callback, on ack|commit
      
      Decode everything in decode_MOSDOpReply() to reduce clutter.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      fe5da05e
    • I
      libceph: drop msg argument from ceph_osdc_callback_t · 85e084fe
      Ilya Dryomov 提交于
      finish_read(), its only user, uses it to get to hdr.data_len, which is
      what ->r_result is set to on success.  This gains us the ability to
      safely call callbacks from contexts other than reply, e.g. map check.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      85e084fe
    • I
      libceph: switch to calc_target(), part 2 · bb873b53
      Ilya Dryomov 提交于
      The crux of this is getting rid of ceph_osdc_build_request(), so that
      MOSDOp can be encoded not before but after calc_target() calculates the
      actual target.  Encoding now happens within ceph_osdc_start_request().
      
      Also nuked is the accompanying bunch of pointers into the encoded
      buffer that was used to update fields on each send - instead, the
      entire front is re-encoded.  If we want to support target->name_len !=
      base->name_len in the future, there is no other way, because oid is
      surrounded by other fields in the encoded buffer.
      
      Encoding OSD ops and adding data items to the request message were
      mixed together in osd_req_encode_op().  While we want to re-encode OSD
      ops, we don't want to add duplicate data items to the message when
      resending, so all call to ceph_osdc_msg_data_add() are factored out
      into a new setup_request_data().
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      bb873b53
    • I
      libceph: switch to calc_target(), part 1 · a66dd383
      Ilya Dryomov 提交于
      Replace __calc_request_pg() and most of __map_request() with
      calc_target() and start using req->r_t.
      
      ceph_osdc_build_request() however still encodes base_oid, because it's
      called before calc_target() is and target_oid is empty at that point in
      time; a printf in osdc_show() also shows base_oid.  This is fixed in
      "libceph: switch to calc_target(), part 2".
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      a66dd383
    • I
      libceph: introduce ceph_osd_request_target, calc_target() · 63244fa1
      Ilya Dryomov 提交于
      Introduce ceph_osd_request_target, containing all mapping-related
      fields of ceph_osd_request and calc_target() for calculating mappings
      and populating it.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      63244fa1
    • I
      libceph: ceph_osds, ceph_pg_to_up_acting_osds() · 6f3bfd45
      Ilya Dryomov 提交于
      Knowning just acting set isn't enough, we need to be able to record up
      set as well to detect interval changes.  This means returning (up[],
      up_len, up_primary, acting[], acting_len, acting_primary) and passing
      it around.  Introduce and switch to ceph_osds to help with that.
      
      Rename ceph_calc_pg_acting() to ceph_pg_to_up_acting_osds() and return
      both up and acting sets from it.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      6f3bfd45
    • I
      libceph: rename ceph_oloc_oid_to_pg() · d9591f5e
      Ilya Dryomov 提交于
      Rename ceph_oloc_oid_to_pg() to ceph_object_locator_to_pg().  Emphasise
      that returned is raw PG and return -ENOENT instead of -EIO if the pool
      doesn't exist.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      d9591f5e
    • I
      libceph: DEFINE_RB_FUNCS macro · fcd00b68
      Ilya Dryomov 提交于
      Given
      
          struct foo {
              u64 id;
              struct rb_node bar_node;
          };
      
      generate insert_bar(), erase_bar() and lookup_bar() functions with
      
          DEFINE_RB_FUNCS(bar, struct foo, id, bar_node)
      
      The key is assumed to be an integer (u64, int, etc), compared with
      < and >.  nodefld has to be initialized with RB_CLEAR_NODE().
      
      Start using it for MDS, MON and OSD requests and OSD sessions.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      fcd00b68
    • I
      libceph: open-code remove_{all,old}_osds() · 42a2c09f
      Ilya Dryomov 提交于
      They are called only once, from ceph_osdc_stop() and
      handle_osds_timeout() respectively.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      42a2c09f
    • I
      libceph: nuke unused fields and functions · 0c0a8de1
      Ilya Dryomov 提交于
      Either unused or useless:
      
          osdmap->mkfs_epoch
          osd->o_marked_for_keepalive
          monc->num_generic_requests
          osdc->map_waiters
          osdc->last_requested_map
          osdc->timeout_tid
      
          osd_req_op_cls_response_data()
      
          osdmap_apply_incremental() @msgr arg
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      0c0a8de1
    • I
      libceph: variable-sized ceph_object_id · d30291b9
      Ilya Dryomov 提交于
      Currently ceph_object_id can hold object names of up to 100
      (CEPH_MAX_OID_NAME_LEN) characters.  This is enough for all use cases,
      expect one - long rbd image names:
      
      - a format 1 header is named "<imgname>.rbd"
      - an object that points to a format 2 header is named "rbd_id.<imgname>"
      
      We operate on these potentially long-named objects during rbd map, and,
      for format 1 images, during header refresh.  (A format 2 header name is
      a small system-generated string.)
      
      Lift this 100 character limit by making ceph_object_id be able to point
      to an externally-allocated string.  Apart from being able to work with
      almost arbitrarily-long named objects, this allows us to reduce the
      size of ceph_object_id from >100 bytes to 64 bytes.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      d30291b9
    • I
      libceph: change how osd_op_reply message size is calculated · 711da55d
      Ilya Dryomov 提交于
      For a message pool message, preallocate a page, just like we do for
      osd_op.  For a normal message, take ceph_object_id into account and
      don't bother subtracting CEPH_OSD_SLAB_OPS ceph_osd_ops.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      711da55d
    • I
      libceph: move message allocation out of ceph_osdc_alloc_request() · 13d1ad16
      Ilya Dryomov 提交于
      The size of ->r_request and ->r_reply messages depends on the size of
      the object name (ceph_object_id), while the size of ceph_osd_request is
      fixed.  Move message allocation into a separate function that would
      have to be called after ceph_object_id and ceph_object_locator (which
      is also going to become variable in size with RADOS namespaces) have
      been filled in:
      
          req = ceph_osdc_alloc_request(...);
          <fill in req->r_base_oid>
          <fill in req->r_base_oloc>
          ceph_osdc_alloc_messages(req);
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      13d1ad16
    • I
      libceph: grab snapc in ceph_osdc_alloc_request() · 84127282
      Ilya Dryomov 提交于
      ceph_osdc_build_request() is going away.  Grab snapc and initialize
      ->r_snapid in ceph_osdc_alloc_request().
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      84127282
    • I
      libceph: make ceph_osdc_put_request() accept NULL · 3ed97d63
      Ilya Dryomov 提交于
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      3ed97d63
  2. 26 4月, 2016 1 次提交
    • I
      libceph: make authorizer destruction independent of ceph_auth_client · 6c1ea260
      Ilya Dryomov 提交于
      Starting the kernel client with cephx disabled and then enabling cephx
      and restarting userspace daemons can result in a crash:
      
          [262671.478162] BUG: unable to handle kernel paging request at ffffebe000000000
          [262671.531460] IP: [<ffffffff811cd04a>] kfree+0x5a/0x130
          [262671.584334] PGD 0
          [262671.635847] Oops: 0000 [#1] SMP
          [262672.055841] CPU: 22 PID: 2961272 Comm: kworker/22:2 Not tainted 4.2.0-34-generic #39~14.04.1-Ubuntu
          [262672.162338] Hardware name: Dell Inc. PowerEdge R720/068CDY, BIOS 2.4.3 07/09/2014
          [262672.268937] Workqueue: ceph-msgr con_work [libceph]
          [262672.322290] task: ffff88081c2d0dc0 ti: ffff880149ae8000 task.ti: ffff880149ae8000
          [262672.428330] RIP: 0010:[<ffffffff811cd04a>]  [<ffffffff811cd04a>] kfree+0x5a/0x130
          [262672.535880] RSP: 0018:ffff880149aeba58  EFLAGS: 00010286
          [262672.589486] RAX: 000001e000000000 RBX: 0000000000000012 RCX: ffff8807e7461018
          [262672.695980] RDX: 000077ff80000000 RSI: ffff88081af2be04 RDI: 0000000000000012
          [262672.803668] RBP: ffff880149aeba78 R08: 0000000000000000 R09: 0000000000000000
          [262672.912299] R10: ffffebe000000000 R11: ffff880819a60e78 R12: ffff8800aec8df40
          [262673.021769] R13: ffffffffc035f70f R14: ffff8807e5b138e0 R15: ffff880da9785840
          [262673.131722] FS:  0000000000000000(0000) GS:ffff88081fac0000(0000) knlGS:0000000000000000
          [262673.245377] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
          [262673.303281] CR2: ffffebe000000000 CR3: 0000000001c0d000 CR4: 00000000001406e0
          [262673.417556] Stack:
          [262673.472943]  ffff880149aeba88 ffff88081af2be04 ffff8800aec8df40 ffff88081af2be04
          [262673.583767]  ffff880149aeba98 ffffffffc035f70f ffff880149aebac8 ffff8800aec8df00
          [262673.694546]  ffff880149aebac8 ffffffffc035c89e ffff8807e5b138e0 ffff8805b047f800
          [262673.805230] Call Trace:
          [262673.859116]  [<ffffffffc035f70f>] ceph_x_destroy_authorizer+0x1f/0x50 [libceph]
          [262673.968705]  [<ffffffffc035c89e>] ceph_auth_destroy_authorizer+0x3e/0x60 [libceph]
          [262674.078852]  [<ffffffffc0352805>] put_osd+0x45/0x80 [libceph]
          [262674.134249]  [<ffffffffc035290e>] remove_osd+0xae/0x140 [libceph]
          [262674.189124]  [<ffffffffc0352aa3>] __reset_osd+0x103/0x150 [libceph]
          [262674.243749]  [<ffffffffc0354703>] kick_requests+0x223/0x460 [libceph]
          [262674.297485]  [<ffffffffc03559e2>] ceph_osdc_handle_map+0x282/0x5e0 [libceph]
          [262674.350813]  [<ffffffffc035022e>] dispatch+0x4e/0x720 [libceph]
          [262674.403312]  [<ffffffffc034bd91>] try_read+0x3d1/0x1090 [libceph]
          [262674.454712]  [<ffffffff810ab7c2>] ? dequeue_entity+0x152/0x690
          [262674.505096]  [<ffffffffc034cb1b>] con_work+0xcb/0x1300 [libceph]
          [262674.555104]  [<ffffffff8108fb3e>] process_one_work+0x14e/0x3d0
          [262674.604072]  [<ffffffff810901ea>] worker_thread+0x11a/0x470
          [262674.652187]  [<ffffffff810900d0>] ? rescuer_thread+0x310/0x310
          [262674.699022]  [<ffffffff810957a2>] kthread+0xd2/0xf0
          [262674.744494]  [<ffffffff810956d0>] ? kthread_create_on_node+0x1c0/0x1c0
          [262674.789543]  [<ffffffff817bd81f>] ret_from_fork+0x3f/0x70
          [262674.834094]  [<ffffffff810956d0>] ? kthread_create_on_node+0x1c0/0x1c0
      
      What happens is the following:
      
          (1) new MON session is established
          (2) old "none" ac is destroyed
          (3) new "cephx" ac is constructed
          ...
          (4) old OSD session (w/ "none" authorizer) is put
                ceph_auth_destroy_authorizer(ac, osd->o_auth.authorizer)
      
      osd->o_auth.authorizer in the "none" case is just a bare pointer into
      ac, which contains a single static copy for all services.  By the time
      we get to (4), "none" ac, freed in (2), is long gone.  On top of that,
      a new vtable installed in (3) points us at ceph_x_destroy_authorizer(),
      so we end up trying to destroy a "none" authorizer with a "cephx"
      destructor operating on invalid memory!
      
      To fix this, decouple authorizer destruction from ac and do away with
      a single static "none" authorizer by making a copy for each OSD or MDS
      session.  Authorizers themselves are independent of ac and so there is
      no reason for destroy_authorizer() to be an ac op.  Make it an op on
      the authorizer itself by turning ceph_authorizer into a real struct.
      
      Fixes: http://tracker.ceph.com/issues/15447Reported-by: NAlan Zhang <alan.zhang@linux.com>
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      Reviewed-by: NSage Weil <sage@redhat.com>
      6c1ea260
  3. 26 3月, 2016 7 次提交
  4. 25 2月, 2016 1 次提交
  5. 05 2月, 2016 1 次提交
  6. 03 11月, 2015 4 次提交
    • I
      libceph: clear msg->con in ceph_msg_release() only · 583d0fef
      Ilya Dryomov 提交于
      The following bit in ceph_msg_revoke_incoming() is unsafe:
      
          struct ceph_connection *con = msg->con;
          if (!con)
                  return;
          mutex_lock(&con->mutex);
          <more msg->con use>
      
      There is nothing preventing con from getting destroyed right after
      msg->con test.  One easy way to reproduce this is to disable message
      signing only on the server side and try to map an image.  The system
      will go into a
      
          libceph: read_partial_message ffff880073f0ab68 signature check failed
          libceph: osd0 192.168.255.155:6801 bad crc/signature
          libceph: read_partial_message ffff880073f0ab68 signature check failed
          libceph: osd0 192.168.255.155:6801 bad crc/signature
      
      loop which has to be interrupted with Ctrl-C.  Hit Ctrl-C and you are
      likely to end up with a random GP fault if the reset handler executes
      "within" ceph_msg_revoke_incoming():
      
                           <yet another reply w/o a signature>
                                         ...
                <Ctrl-C>
          rbd_obj_request_end
            ceph_osdc_cancel_request
              __unregister_request
                ceph_osdc_put_request
                  ceph_msg_revoke_incoming
                                         ...
                                      osd_reset
                                        __kick_osd_requests
                                          __reset_osd
                                            remove_osd
                                              ceph_con_close
                                                reset_connection
                                                  <clear con->in_msg->con>
                                                  <put con ref>
                                                    put_osd
                                                      <free osd/con>
                    <msg->con use> <-- !!!
      
      If ceph_msg_revoke_incoming() executes "before" the reset handler,
      osd/con will be leaked because ceph_msg_revoke_incoming() clears
      con->in_msg but doesn't put con ref, while reset_connection() only puts
      con ref if con->in_msg != NULL.
      
      The current msg->con scheme was introduced by commits 38941f80
      ("libceph: have messages point to their connection") and 92ce034b
      ("libceph: have messages take a connection reference"), which defined
      when messages get associated with a connection and when that
      association goes away.  Part of the problem is that this association is
      supposed to go away in much too many places; closing this race entirely
      requires either a rework of the existing or an addition of a new layer
      of synchronization.
      
      In lieu of that, we can make it *much* less likely to hit by
      disassociating messages only on their destruction and resend through
      a different connection.  This makes the code simpler and is probably
      a good thing to do regardless - this patch adds a msg_con_set() helper
      which is is called from only three places: ceph_con_send() and
      ceph_con_in_msg_alloc() to set msg->con and ceph_msg_release() to clear
      it.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      583d0fef
    • I
      libceph: msg signing callouts don't need con argument · 79dbd1ba
      Ilya Dryomov 提交于
      We can use msg->con instead - at the point we sign an outgoing message
      or check the signature on the incoming one, msg->con is always set.  We
      wouldn't know how to sign a message without an associated session (i.e.
      msg->con == NULL) and being able to sign a message using an explicitly
      provided authorizer is of no use.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      79dbd1ba
    • I
      libceph: evaluate osd_req_op_data() arguments only once · 8a703a38
      Ioana Ciornei 提交于
      This patch changes the osd_req_op_data() macro to not evaluate
      arguments more than once in order to follow the kernel coding style.
      Signed-off-by: NIoana Ciornei <ciorneiioana@gmail.com>
      Reviewed-by: NAlex Elder <elder@linaro.org>
      [idryomov@gmail.com: changelog, formatting]
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      8a703a38
    • S
      libceph: remove con argument in handle_reply() · 70cf052d
      Shraddha Barke 提交于
      Since handle_reply() does not use its con argument, remove it.
      Signed-off-by: NShraddha Barke <shraddha.6596@gmail.com>
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      70cf052d
  7. 16 10月, 2015 1 次提交
    • I
      rbd: use writefull op for object size writes · e30b7577
      Ilya Dryomov 提交于
      This covers only the simplest case - an object size sized write, but
      it's still useful in tiering setups when EC is used for the base tier
      as writefull op can be proxied, saving an object promotion.
      
      Even though updating ceph_osdc_new_request() to allow writefull should
      just be a matter of fixing an assert, I didn't do it because its only
      user is cephfs.  All other sites were updated.
      
      Reflects ceph.git commit 7bfb7f9025a8ee0d2305f49bf0336d2424da5b5b.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      Reviewed-by: NAlex Elder <elder@linaro.org>
      e30b7577
  8. 09 9月, 2015 1 次提交
    • I
      libceph: check data_len in ->alloc_msg() · d15f9d69
      Ilya Dryomov 提交于
      Only ->alloc_msg() should check data_len of the incoming message
      against the preallocated ceph_msg, doing it in the messenger is not
      right.  The contract is that either ->alloc_msg() returns a ceph_msg
      which will fit all of the portions of the incoming message, or it
      returns NULL and possibly sets skip, signaling whether NULL is due to
      an -ENOMEM.  ->alloc_msg() should be the only place where we make the
      skip/no-skip decision.
      
      I stumbled upon this while looking at con/osd ref counting.  Right now,
      if we get a non-extent message with a larger data portion than we are
      prepared for, ->alloc_msg() returns a ceph_msg, and then, when we skip
      it in the messenger, we don't put the con/osd ref acquired in
      ceph_con_in_msg_alloc() (which is normally put in process_message()),
      so this also fixes a memory leak.
      
      An existing BUG_ON in ceph_msg_data_cursor_init() ensures we don't
      corrupt random memory should a buggy ->alloc_msg() return an unfit
      ceph_msg.
      
      While at it, I changed the "unknown tid" dout() to a pr_warn() to make
      sure all skips are seen and unified format strings.
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      Reviewed-by: NAlex Elder <elder@linaro.org>
      d15f9d69
  9. 25 6月, 2015 3 次提交
  10. 21 5月, 2015 2 次提交
    • I
      Revert "libceph: clear r_req_lru_item in __unregister_linger_request()" · 521a04d0
      Ilya Dryomov 提交于
      This reverts commit ba9d114e.
      
      .. which introduced a regression that prevented all lingering requests
      requeued in kick_requests() from ever being sent to the OSDs, resulting
      in a lot of missed notifies.  In retrospect it's pretty obvious that
      r_req_lru_item item in the case of lingering requests can be used not
      only for notarget, but also for unsent linkage due to how tightly
      actual map and enqueue operations are coupled in __map_request().
      
      The assertion that was being silenced is taken care of in the previous
      ("libceph: request a new osdmap if lingering request maps to no osd")
      commit: by always kicking homeless lingering requests we ensure that
      none of them ends up on the notarget list outside of the critical
      section guarded by request_mutex.
      
      Cc: stable@vger.kernel.org # 3.18+, needs b0494532 "libceph: request a new osdmap if lingering request maps to no osd"
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      Reviewed-by: NSage Weil <sage@redhat.com>
      521a04d0
    • I
      libceph: request a new osdmap if lingering request maps to no osd · b0494532
      Ilya Dryomov 提交于
      This commit does two things.  First, if there are any homeless
      lingering requests, we now request a new osdmap even if the osdmap that
      is being processed brought no changes, i.e. if a given lingering
      request turned homeless in one of the previous epochs and remained
      homeless in the current epoch.  Not doing so leaves us with a stale
      osdmap and as a result we may miss our window for reestablishing the
      watch and lose notifies.
      
      MON=1 OSD=1:
      
          # cat linger-needmap.sh
          #!/bin/bash
          rbd create --size 1 test
          DEV=$(rbd map test)
          ceph osd out 0
          rbd map dne/dne # obtain a new osdmap as a side effect (!)
          sleep 1
          ceph osd in 0
          rbd resize --size 2 test
          # rbd info test | grep size -> 2M
          # blockdev --getsize $DEV -> 1M
      
      N.B.: Not obtaining a new osdmap in between "osd out" and "osd in"
      above is enough to make it miss that resize notify, but that is a
      bug^Wlimitation of ceph watch/notify v1.
      
      Second, homeless lingering requests are now kicked just like those
      lingering requests whose mapping has changed.  This is mainly to
      recognize that a homeless lingering request makes no sense and to
      preserve the invariant that a registered lingering request is not
      sitting on any of r_req_lru_item lists.  This spares us a WARN_ON,
      which commit ba9d114e ("libceph: clear r_req_lru_item in
      __unregister_linger_request()") tried to fix the _wrong_ way.
      
      Cc: stable@vger.kernel.org # 3.10+
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      Reviewed-by: NSage Weil <sage@redhat.com>
      b0494532
  11. 19 2月, 2015 2 次提交
    • I
      libceph: kfree() in put_osd() shouldn't depend on authorizer · b28ec2f3
      Ilya Dryomov 提交于
      a255651d ("ceph: ensure auth ops are defined before use") made
      kfree() in put_osd() conditional on the authorizer.  A mechanical
      mistake most likely - fix it.
      
      Cc: Alex Elder <elder@linaro.org>
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      Reviewed-by: NSage Weil <sage@redhat.com>
      Reviewed-by: NAlex Elder <elder@linaro.org>
      b28ec2f3
    • I
      libceph: fix double __remove_osd() problem · 7eb71e03
      Ilya Dryomov 提交于
      It turns out it's possible to get __remove_osd() called twice on the
      same OSD.  That doesn't sit well with rb_erase() - depending on the
      shape of the tree we can get a NULL dereference, a soft lockup or
      a random crash at some point in the future as we end up touching freed
      memory.  One scenario that I was able to reproduce is as follows:
      
                  <osd3 is idle, on the osd lru list>
      <con reset - osd3>
      con_fault_finish()
        osd_reset()
                                    <osdmap - osd3 down>
                                    ceph_osdc_handle_map()
                                      <takes map_sem>
                                      kick_requests()
                                        <takes request_mutex>
                                        reset_changed_osds()
                                          __reset_osd()
                                            __remove_osd()
                                        <releases request_mutex>
                                      <releases map_sem>
          <takes map_sem>
          <takes request_mutex>
          __kick_osd_requests()
            __reset_osd()
              __remove_osd() <-- !!!
      
      A case can be made that osd refcounting is imperfect and reworking it
      would be a proper resolution, but for now Sage and I decided to fix
      this by adding a safe guard around __remove_osd().
      
      Fixes: http://tracker.ceph.com/issues/8087
      
      Cc: Sage Weil <sage@redhat.com>
      Cc: stable@vger.kernel.org # 3.9+: 7c6e6fc5: libceph: assert both regular and lingering lists in __remove_osd()
      Cc: stable@vger.kernel.org # 3.9+: cc9f1f51: libceph: change from BUG to WARN for __remove_osd() asserts
      Cc: stable@vger.kernel.org # 3.9+
      Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
      Reviewed-by: NSage Weil <sage@redhat.com>
      Reviewed-by: NAlex Elder <elder@linaro.org>
      7eb71e03
  12. 18 12月, 2014 1 次提交