lkml.org 
[lkml]   [2015]   [Jun]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 3.4 136/172] net: use for_each_netdev_safe() in rtnl_group_changelink()
    Date
    From: WANG Cong <xiyou.wangcong@gmail.com>

    3.4.108-rc1 review patch. If anyone has any objections, please let me know.

    ------------------


    commit d079535d5e1bf5e2e7c856bae2483414ea21e137 upstream.

    In case we move the whole dev group to another netns,
    we should call for_each_netdev_safe(), otherwise we get
    a soft lockup:

    NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [ip:798]
    irq event stamp: 255424
    hardirqs last enabled at (255423): [<ffffffff81a2aa95>] restore_args+0x0/0x30
    hardirqs last disabled at (255424): [<ffffffff81a2ad5a>] apic_timer_interrupt+0x6a/0x80
    softirqs last enabled at (255422): [<ffffffff81079ebc>] __do_softirq+0x2c1/0x3a9
    softirqs last disabled at (255417): [<ffffffff8107a190>] irq_exit+0x41/0x95
    CPU: 0 PID: 798 Comm: ip Not tainted 4.0.0-rc4+ #881
    Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
    task: ffff8800d1b88000 ti: ffff880119530000 task.ti: ffff880119530000
    RIP: 0010:[<ffffffff810cad11>] [<ffffffff810cad11>] debug_lockdep_rcu_enabled+0x28/0x30
    RSP: 0018:ffff880119533778 EFLAGS: 00000246
    RAX: ffff8800d1b88000 RBX: 0000000000000002 RCX: 0000000000000038
    RDX: 0000000000000000 RSI: ffff8800d1b888c8 RDI: ffff8800d1b888c8
    RBP: ffff880119533778 R08: 0000000000000000 R09: 0000000000000000
    R10: 0000000000000000 R11: 000000000000b5c2 R12: 0000000000000246
    R13: ffff880119533708 R14: 00000000001d5a40 R15: ffff88011a7d5a40
    FS: 00007fc01315f740(0000) GS:ffff88011a600000(0000) knlGS:0000000000000000
    CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
    CR2: 00007f367a120988 CR3: 000000011849c000 CR4: 00000000000007f0
    Stack:
    ffff880119533798 ffffffff811ac868 ffffffff811ac831 ffffffff811ac828
    ffff8801195337c8 ffffffff811ac8c9 ffff8801195339b0 ffff8801197633e0
    0000000000000000 ffff8801195339b0 ffff8801195337d8 ffffffff811ad2d7
    Call Trace:
    [<ffffffff811ac868>] rcu_read_lock+0x37/0x6e
    [<ffffffff811ac831>] ? rcu_read_unlock+0x5f/0x5f
    [<ffffffff811ac828>] ? rcu_read_unlock+0x56/0x5f
    [<ffffffff811ac8c9>] __fget+0x2a/0x7a
    [<ffffffff811ad2d7>] fget+0x13/0x15
    [<ffffffff811be732>] proc_ns_fget+0xe/0x38
    [<ffffffff817c7714>] get_net_ns_by_fd+0x11/0x59
    [<ffffffff817df359>] rtnl_link_get_net+0x33/0x3e
    [<ffffffff817df3d7>] do_setlink+0x73/0x87b
    [<ffffffff810b28ce>] ? trace_hardirqs_off+0xd/0xf
    [<ffffffff81a2aa95>] ? retint_restore_args+0xe/0xe
    [<ffffffff817e0301>] rtnl_newlink+0x40c/0x699
    [<ffffffff817dffe0>] ? rtnl_newlink+0xeb/0x699
    [<ffffffff81a29246>] ? _raw_spin_unlock+0x28/0x33
    [<ffffffff8143ed1e>] ? security_capable+0x18/0x1a
    [<ffffffff8107da51>] ? ns_capable+0x4d/0x65
    [<ffffffff817de5ce>] rtnetlink_rcv_msg+0x181/0x194
    [<ffffffff817de407>] ? rtnl_lock+0x17/0x19
    [<ffffffff817de407>] ? rtnl_lock+0x17/0x19
    [<ffffffff817de44d>] ? __rtnl_unlock+0x17/0x17
    [<ffffffff818327c6>] netlink_rcv_skb+0x4d/0x93
    [<ffffffff817de42f>] rtnetlink_rcv+0x26/0x2d
    [<ffffffff81830f18>] netlink_unicast+0xcb/0x150
    [<ffffffff8183198e>] netlink_sendmsg+0x501/0x523
    [<ffffffff8115cba9>] ? might_fault+0x59/0xa9
    [<ffffffff817b5398>] ? copy_from_user+0x2a/0x2c
    [<ffffffff817b7b74>] sock_sendmsg+0x34/0x3c
    [<ffffffff817b7f6d>] ___sys_sendmsg+0x1b8/0x255
    [<ffffffff8115c5eb>] ? handle_pte_fault+0xbd5/0xd4a
    [<ffffffff8100a2b0>] ? native_sched_clock+0x35/0x37
    [<ffffffff8109e94b>] ? sched_clock_local+0x12/0x72
    [<ffffffff8109eb9c>] ? sched_clock_cpu+0x9e/0xb7
    [<ffffffff810cadbf>] ? rcu_read_lock_held+0x3b/0x3d
    [<ffffffff811ac1d8>] ? __fcheck_files+0x4c/0x58
    [<ffffffff811ac946>] ? __fget_light+0x2d/0x52
    [<ffffffff817b8adc>] __sys_sendmsg+0x42/0x60
    [<ffffffff817b8b0c>] SyS_sendmsg+0x12/0x1c
    [<ffffffff81a29e32>] system_call_fastpath+0x12/0x17

    Fixes: e7ed828f10bd8 ("netlink: support setting devgroup parameters")
    Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
    Signed-off-by: David S. Miller <davem@davemloft.net>
    Signed-off-by: Zefan Li <lizefan@huawei.com>
    ---
    net/core/rtnetlink.c | 4 ++--
    1 file changed, 2 insertions(+), 2 deletions(-)

    diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
    index 42c2596..43c6dd8 100644
    --- a/net/core/rtnetlink.c
    +++ b/net/core/rtnetlink.c
    @@ -1694,10 +1694,10 @@ static int rtnl_group_changelink(struct net *net, int group,
    struct ifinfomsg *ifm,
    struct nlattr **tb)
    {
    - struct net_device *dev;
    + struct net_device *dev, *aux;
    int err;

    - for_each_netdev(net, dev) {
    + for_each_netdev_safe(net, dev, aux) {
    if (dev->group == group) {
    err = do_setlink(dev, ifm, tb, NULL, 0);
    if (err < 0)
    --
    1.9.1


    \
     
     \ /
      Last update: 2015-06-16 11:21    [W:4.114 / U:0.256 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site