1. 13 Aug, 2013 12 commits
  2. 12 Aug, 2013 3 commits
    • dingtianhong's avatar
      tipc: avoid possible deadlock while enable and disable bearer · d4cca39d
      dingtianhong authored
      We met lockdep warning when enable and disable the bearer for commands such as:
      
      tipc-config -netid=1234 -addr=1.1.3 -be=eth:eth0
      tipc-config -netid=1234 -addr=1.1.3 -bd=eth:eth0
      
      ---------------------------------------------------
      
      [  327.693595] ======================================================
      [  327.693994] [ INFO: possible circular locking dependency detected ]
      [  327.694519] 3.11.0-rc3-wwd-default #4 Tainted: G           O
      [  327.694882] -------------------------------------------------------
      [  327.695385] tipc-config/5825 is trying to acquire lock:
      [  327.695754]  (((timer))#2){+.-...}, at: [<ffffffff8105be80>] del_timer_sync+0x0/0xd0
      [  327.696018]
      [  327.696018] but task is already holding lock:
      [  327.696018]  (&(&b_ptr->lock)->rlock){+.-...}, at: [<ffffffffa02be58d>] bearer_disable+  0xdd/0x120 [tipc]
      [  327.696018]
      [  327.696018] which lock already depends on the new lock.
      [  327.696018]
      [  327.696018]
      [  327.696018] the existing dependency chain (in reverse order) is:
      [  327.696018]
      [  327.696018] -> #1 (&(&b_ptr->lock)->rlock){+.-...}:
      [  327.696018]        [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
      [  327.696018]        [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
      [  327.696018]        [<ffffffff810b4453>] lock_acquire+0x103/0x130
      [  327.696018]        [<ffffffff814d65b1>] _raw_spin_lock_bh+0x41/0x80
      [  327.696018]        [<ffffffffa02c5d48>] disc_timeout+0x18/0xd0 [tipc]
      [  327.696018]        [<ffffffff8105b92a>] call_timer_fn+0xda/0x1e0
      [  327.696018]        [<ffffffff8105bcd7>] run_timer_softirq+0x2a7/0x2d0
      [  327.696018]        [<ffffffff8105379a>] __do_softirq+0x16a/0x2e0
      [  327.696018]        [<ffffffff81053a35>] irq_exit+0xd5/0xe0
      [  327.696018]        [<ffffffff81033005>] smp_apic_timer_interrupt+0x45/0x60
      [  327.696018]        [<ffffffff814df4af>] apic_timer_interrupt+0x6f/0x80
      [  327.696018]        [<ffffffff8100b70e>] arch_cpu_idle+0x1e/0x30
      [  327.696018]        [<ffffffff810a039d>] cpu_idle_loop+0x1fd/0x280
      [  327.696018]        [<ffffffff810a043e>] cpu_startup_entry+0x1e/0x20
      [  327.696018]        [<ffffffff81031589>] start_secondary+0x89/0x90
      [  327.696018]
      [  327.696018] -> #0 (((timer))#2){+.-...}:
      [  327.696018]        [<ffffffff810b33fe>] check_prev_add+0x43e/0x4b0
      [  327.696018]        [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
      [  327.696018]        [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
      [  327.696018]        [<ffffffff810b4453>] lock_acquire+0x103/0x130
      [  327.696018]        [<ffffffff8105bebd>] del_timer_sync+0x3d/0xd0
      [  327.696018]        [<ffffffffa02c5855>] tipc_disc_delete+0x15/0x30 [tipc]
      [  327.696018]        [<ffffffffa02be59f>] bearer_disable+0xef/0x120 [tipc]
      [  327.696018]        [<ffffffffa02be74f>] tipc_disable_bearer+0x2f/0x60 [tipc]
      [  327.696018]        [<ffffffffa02bfb32>] tipc_cfg_do_cmd+0x2e2/0x550 [tipc]
      [  327.696018]        [<ffffffffa02c8c79>] handle_cmd+0x49/0xe0 [tipc]
      [  327.696018]        [<ffffffff8143e898>] genl_family_rcv_msg+0x268/0x340
      [  327.696018]        [<ffffffff8143ed30>] genl_rcv_msg+0x70/0xd0
      [  327.696018]        [<ffffffff8143d4c9>] netlink_rcv_skb+0x89/0xb0
      [  327.696018]        [<ffffffff8143e617>] genl_rcv+0x27/0x40
      [  327.696018]        [<ffffffff8143d21e>] netlink_unicast+0x15e/0x1b0
      [  327.696018]        [<ffffffff8143ddcf>] netlink_sendmsg+0x22f/0x400
      [  327.696018]        [<ffffffff813f7836>] __sock_sendmsg+0x66/0x80
      [  327.696018]        [<ffffffff813f7957>] sock_aio_write+0x107/0x120
      [  327.696018]        [<ffffffff8117f76d>] do_sync_write+0x7d/0xc0
      [  327.696018]        [<ffffffff8117fc56>] vfs_write+0x186/0x190
      [  327.696018]        [<ffffffff811803e0>] SyS_write+0x60/0xb0
      [  327.696018]        [<ffffffff814de852>] system_call_fastpath+0x16/0x1b
      [  327.696018]
      [  327.696018] other info that might help us debug this:
      [  327.696018]
      [  327.696018]  Possible unsafe locking scenario:
      [  327.696018]
      [  327.696018]        CPU0                    CPU1
      [  327.696018]        ----                    ----
      [  327.696018]   lock(&(&b_ptr->lock)->rlock);
      [  327.696018]                                lock(((timer))#2);
      [  327.696018]                                lock(&(&b_ptr->lock)->rlock);
      [  327.696018]   lock(((timer))#2);
      [  327.696018]
      [  327.696018]  *** DEADLOCK ***
      [  327.696018]
      [  327.696018] 5 locks held by tipc-config/5825:
      [  327.696018]  #0:  (cb_lock){++++++}, at: [<ffffffff8143e608>] genl_rcv+0x18/0x40
      [  327.696018]  #1:  (genl_mutex){+.+.+.}, at: [<ffffffff8143ed66>] genl_rcv_msg+0xa6/0xd0
      [  327.696018]  #2:  (config_mutex){+.+.+.}, at: [<ffffffffa02bf889>] tipc_cfg_do_cmd+0x39/ 0x550 [tipc]
      [  327.696018]  #3:  (tipc_net_lock){++.-..}, at: [<ffffffffa02be738>] tipc_disable_bearer+ 0x18/0x60 [tipc]
      [  327.696018]  #4:  (&(&b_ptr->lock)->rlock){+.-...}, at: [<ffffffffa02be58d>]             bearer_disable+0xdd/0x120 [tipc]
      [  327.696018]
      [  327.696018] stack backtrace:
      [  327.696018] CPU: 2 PID: 5825 Comm: tipc-config Tainted: G           O 3.11.0-rc3-wwd-    default #4
      [  327.696018] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
      [  327.696018]  00000000ffffffff ffff880037fa77a8 ffffffff814d03dd 0000000000000000
      [  327.696018]  ffff880037fa7808 ffff880037fa77e8 ffffffff810b1c4f 0000000037fa77e8
      [  327.696018]  ffff880037fa7808 ffff880037e4db40 0000000000000000 ffff880037e4e318
      [  327.696018] Call Trace:
      [  327.696018]  [<ffffffff814d03dd>] dump_stack+0x4d/0xa0
      [  327.696018]  [<ffffffff810b1c4f>] print_circular_bug+0x10f/0x120
      [  327.696018]  [<ffffffff810b33fe>] check_prev_add+0x43e/0x4b0
      [  327.696018]  [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
      [  327.696018]  [<ffffffff81087a28>] ? sched_clock_cpu+0xd8/0x110
      [  327.696018]  [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
      [  327.696018]  [<ffffffff810b4453>] lock_acquire+0x103/0x130
      [  327.696018]  [<ffffffff8105be80>] ? try_to_del_timer_sync+0x70/0x70
      [  327.696018]  [<ffffffff8105bebd>] del_timer_sync+0x3d/0xd0
      [  327.696018]  [<ffffffff8105be80>] ? try_to_del_timer_sync+0x70/0x70
      [  327.696018]  [<ffffffffa02c5855>] tipc_disc_delete+0x15/0x30 [tipc]
      [  327.696018]  [<ffffffffa02be59f>] bearer_disable+0xef/0x120 [tipc]
      [  327.696018]  [<ffffffffa02be74f>] tipc_disable_bearer+0x2f/0x60 [tipc]
      [  327.696018]  [<ffffffffa02bfb32>] tipc_cfg_do_cmd+0x2e2/0x550 [tipc]
      [  327.696018]  [<ffffffff81218783>] ? security_capable+0x13/0x20
      [  327.696018]  [<ffffffffa02c8c79>] handle_cmd+0x49/0xe0 [tipc]
      [  327.696018]  [<ffffffff8143e898>] genl_family_rcv_msg+0x268/0x340
      [  327.696018]  [<ffffffff8143ed30>] genl_rcv_msg+0x70/0xd0
      [  327.696018]  [<ffffffff8143ecc0>] ? genl_lock+0x20/0x20
      [  327.696018]  [<ffffffff8143d4c9>] netlink_rcv_skb+0x89/0xb0
      [  327.696018]  [<ffffffff8143e608>] ? genl_rcv+0x18/0x40
      [  327.696018]  [<ffffffff8143e617>] genl_rcv+0x27/0x40
      [  327.696018]  [<ffffffff8143d21e>] netlink_unicast+0x15e/0x1b0
      [  327.696018]  [<ffffffff81289d7c>] ? memcpy_fromiovec+0x6c/0x90
      [  327.696018]  [<ffffffff8143ddcf>] netlink_sendmsg+0x22f/0x400
      [  327.696018]  [<ffffffff813f7836>] __sock_sendmsg+0x66/0x80
      [  327.696018]  [<ffffffff813f7957>] sock_aio_write+0x107/0x120
      [  327.696018]  [<ffffffff813fe29c>] ? release_sock+0x8c/0xa0
      [  327.696018]  [<ffffffff8117f76d>] do_sync_write+0x7d/0xc0
      [  327.696018]  [<ffffffff8117fa24>] ? rw_verify_area+0x54/0x100
      [  327.696018]  [<ffffffff8117fc56>] vfs_write+0x186/0x190
      [  327.696018]  [<ffffffff811803e0>] SyS_write+0x60/0xb0
      [  327.696018]  [<ffffffff814de852>] system_call_fastpath+0x16/0x1b
      
      -----------------------------------------------------------------------
      
      The problem is that the tipc_link_delete() will cancel the timer disc_timeout() when
      the b_ptr->lock is hold, but the disc_timeout() still call b_ptr->lock to finish the
      work, so the dead lock occurs.
      
      We should unlock the b_ptr->lock when del the disc_timeout().
      
      Remove link_timeout() still met the same problem, the patch:
      
      http://article.gmane.org/gmane.network.tipc.general/4380
      
      fix the problem, so no need to send patch for fix link_timeout() deadlock warming.
      Signed-off-by: default avatarWang Weidong <wangweidong1@huawei.com>
      Signed-off-by: default avatarDing Tianhong <dingtianhong@huawei.com>
      Acked-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d4cca39d
    • Stephane Grosjean's avatar
      can: pcan_usb: fix wrong memcpy() bytes length · 3c322a56
      Stephane Grosjean authored
      Fix possibly wrong memcpy() bytes length since some CAN records received from
      PCAN-USB could define a DLC field in range [9..15].
      In that case, the real DLC value MUST be used to move forward the record pointer
      but, only 8 bytes max. MUST be copied into the data field of the struct
      can_frame object of the skb given to the network core.
      
      Cc: linux-stable <stable@vger.kernel.org>
      Signed-off-by: default avatarStephane Grosjean <s.grosjean@peak-system.com>
      Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3c322a56
    • Eric Dumazet's avatar
      macvtap: fix two races · 29d79196
      Eric Dumazet authored
      Since commit ac4e4af1 ("macvtap: Consistently use rcu functions"),
      Thomas gets two different warnings :
      
      BUG: using smp_processor_id() in preemptible [00000000] code: vhost-45891/45892
      caller is macvtap_do_read+0x45c/0x600 [macvtap]
      CPU: 1 PID: 45892 Comm: vhost-45891 Not tainted 3.11.0-bisecttest #13
      Call Trace:
      ([<00000000001126ee>] show_trace+0x126/0x144)
       [<00000000001127d2>] show_stack+0xc6/0xd4
       [<000000000068bcec>] dump_stack+0x74/0xd8
       [<0000000000481066>] debug_smp_processor_id+0xf6/0x114
       [<000003ff802e9a18>] macvtap_do_read+0x45c/0x600 [macvtap]
       [<000003ff802e9c1c>] macvtap_recvmsg+0x60/0x88 [macvtap]
       [<000003ff80318c5e>] handle_rx+0x5b2/0x800 [vhost_net]
       [<000003ff8028f77c>] vhost_worker+0x15c/0x1c4 [vhost]
       [<000000000015f3ac>] kthread+0xd8/0xe4
       [<00000000006934a6>] kernel_thread_starter+0x6/0xc
       [<00000000006934a0>] kernel_thread_starter+0x0/0xc
      
      And
      
      BUG: using smp_processor_id() in preemptible [00000000] code: vhost-45897/45898
      caller is macvlan_start_xmit+0x10a/0x1b4 [macvlan]
      CPU: 1 PID: 45898 Comm: vhost-45897 Not tainted 3.11.0-bisecttest #16
      Call Trace:
      ([<00000000001126ee>] show_trace+0x126/0x144)
       [<00000000001127d2>] show_stack+0xc6/0xd4
       [<000000000068bdb8>] dump_stack+0x74/0xd4
       [<0000000000481132>] debug_smp_processor_id+0xf6/0x114
       [<000003ff802b72ca>] macvlan_start_xmit+0x10a/0x1b4 [macvlan]
       [<000003ff802ea69a>] macvtap_get_user+0x982/0xbc4 [macvtap]
       [<000003ff802ea92a>] macvtap_sendmsg+0x4e/0x60 [macvtap]
       [<000003ff8031947c>] handle_tx+0x494/0x5ec [vhost_net]
       [<000003ff8028f77c>] vhost_worker+0x15c/0x1c4 [vhost]
       [<000000000015f3ac>] kthread+0xd8/0xe4
       [<000000000069356e>] kernel_thread_starter+0x6/0xc
       [<0000000000693568>] kernel_thread_starter+0x0/0xc
      2 locks held by vhost-45897/45898:
       #0:  (&vq->mutex){+.+.+.}, at: [<000003ff8031903c>] handle_tx+0x54/0x5ec [vhost_net]
       #1:  (rcu_read_lock){.+.+..}, at: [<000003ff802ea53c>] macvtap_get_user+0x824/0xbc4 [macvtap]
      
      In the first case, macvtap_put_user() calls macvlan_count_rx()
      in a preempt-able context, and this is not allowed.
      
      In the second case, macvtap_get_user() calls
      macvlan_start_xmit() with BH enabled, and this is not allowed.
      Reported-by: default avatarThomas Huth <thuth@linux.vnet.ibm.com>
      Bisected-by: default avatarThomas Huth <thuth@linux.vnet.ibm.com>
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Tested-by: default avatarThomas Huth <thuth@linux.vnet.ibm.com>
      Cc: Vlad Yasevich <vyasevic@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      29d79196
  3. 10 Aug, 2013 5 commits
  4. 09 Aug, 2013 7 commits
  5. 08 Aug, 2013 3 commits
  6. 07 Aug, 2013 3 commits
  7. 05 Aug, 2013 7 commits