From mboxrd@z Thu Jan  1 00:00:00 1970
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From: Mat Martineau <mathew.j.martineau at linux.intel.com>
To: mptcp at lists.01.org
Subject: [MPTCP] Re: [MPTCP][PATCH v2 mptcp-next 2/3] mptcp: send ack for
 rm_addr
Date: Tue, 16 Mar 2021 17:31:38 -0700
Message-ID: <f2981983-c08d-4c21-93f2-5fb7a9b58ea4@linux.intel.com>
In-Reply-To: b6c36865d72a9fc55d3a926ebdbfad6b95390cea.1615871979.git.geliangtang@gmail.com
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On Tue, 16 Mar 2021, Geliang Tang wrote:

> This patch changes the sending ACK conditions for the ADD_ADDR, send an
> ACK packet for RM_ADDR too.
>
> In mptcp_pm_remove_addr, invoke mptcp_pm_nl_add_addr_send_ack to send
> the ACK packet.
>
> Signed-off-by: Geliang Tang <geliangtang(a)gmail.com>
> ---
> net/mptcp/pm.c         |  1 +
> net/mptcp/pm_netlink.c | 10 +++++-----
> net/mptcp/protocol.h   |  1 +
> 3 files changed, 7 insertions(+), 5 deletions(-)
>

Thanks for the v2 update!

The code looked ok on visual inspection, but I ran in to problems with =

mptcp_join.sh tests (looks like the "remove id 0 address" test that =

triggers it):

[  286.809888] =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
[  286.810818] WARNING: bad unlock balance detected!
[  286.811921] 5.12.0-rc2+ #5 Tainted: G        W
[  286.813119] -------------------------------------
[  286.814218] pm_nl_ctl/3445 is trying to release lock (&msk->pm.lock) =

at:
[  286.815822] [<ffffffffa5ede78b>] mptcp_pm_nl_addr_send_ack+0xab/0x1a0
[  286.816979] but there are no more locks to release!
[  286.817795]
[  286.817795] other info that might help us debug this:
[  286.818874] 3 locks held by pm_nl_ctl/3445:
[  286.819598]  #0: ffffffffa7514770 (cb_lock){++++}-{3:3}, at: =

genl_rcv+0x10/0x30
[  286.820982]  #1: ffffffffa7514828 (genl_mutex){+.+.}-{3:3}, at: =

genl_rcv_msg+0x1f5/0x2c0
[  286.822520]  #2: ffff888104840120 (sk_lock-AF_INET){+.+.}-{0:0}, at: =

mptcp_nl_remove_id_zero_address+0x10f/0x280
[  286.824648]
[  286.824648] stack backtrace:
[  286.825355] CPU: 1 PID: 3445 Comm: pm_nl_ctl Tainted: G        W =

5.12.0-rc2+ #5
[  286.826666] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS =

1.14.0-1.fc33 04/01/2014
[  286.828234] Call Trace:
[  286.828688]  dump_stack+0x93/0xc2
[  286.829296]  lock_release.cold+0x10/0x4e
[  286.830000]  ? mptcp_pm_nl_addr_send_ack+0xab/0x1a0
[  286.830833]  ? lock_downgrade+0x390/0x390
[  286.831553]  ? __mptcp_flush_join_list+0x20/0x180
[  286.832480]  _raw_spin_unlock_bh+0x12/0x30
[  286.833409]  mptcp_pm_nl_addr_send_ack+0xab/0x1a0
[  286.834453]  mptcp_pm_remove_addr+0x7a/0xb0
[  286.835203]  mptcp_nl_remove_id_zero_address+0x11f/0x280
[  286.836204]  ? lookup_subflow_by_saddr+0x1a0/0x1a0
[  286.837116]  ? mptcp_nl_fill_addr+0x320/0x320
[  286.837848]  ? lock_release+0x1d0/0x400
[  286.838565]  ? lock_release+0x1d0/0x400
[  286.839302]  mptcp_nl_cmd_del_addr+0x497/0x5e0
[  286.840130]  ? mptcp_pm_remove_anno_addr.isra.0+0x180/0x180
[  286.841165]  ? nla_get_range_signed+0x1c0/0x1c0
[  286.842053]  ? lock_is_held_type+0x98/0x110
[  286.842820]  ? __nla_parse+0x22/0x30
[  286.843503]  ? genl_family_rcv_msg_attrs_parse.constprop.0+0xd1/0x130
[  286.844739]  genl_family_rcv_msg_doit+0x17a/0x200
[  286.845641]  ? genl_family_rcv_msg_attrs_parse.constprop.0+0x130/0x130
[  286.847167]  ? security_capable+0x48/0x60
[  286.848086]  genl_rcv_msg+0x18d/0x2c0
[  286.848873]  ? genl_get_cmd+0x1b0/0x1b0
[  286.849780]  ? genl_rcv+0x10/0x30
[  286.850730]  ? mptcp_pm_remove_anno_addr.isra.0+0x180/0x180
[  286.852074]  ? netlink_deliver_tap+0xa6/0x570
[  286.852801]  netlink_rcv_skb+0xc4/0x1f0
[  286.853434]  ? find_held_lock+0x85/0xa0
[  286.854074]  ? genl_get_cmd+0x1b0/0x1b0
[  286.854713]  ? netlink_ack+0x4f0/0x4f0
[  286.855336]  genl_rcv+0x1f/0x30
[  286.855863]  netlink_unicast+0x2d3/0x410
[  286.856516]  ? netlink_attachskb+0x400/0x400
[  286.857219]  ? _copy_from_iter_full+0xd8/0x360
[  286.857986]  netlink_sendmsg+0x394/0x670
[  286.858644]  ? netlink_unicast+0x410/0x410
[  286.859343]  ? netlink_unicast+0x410/0x410
[  286.860256]  sock_sendmsg+0x91/0xa0
[  286.861032]  __sys_sendto+0x16e/0x210
[  286.861881]  ? __ia32_sys_getpeername+0x40/0x40
[  286.862902]  ? handle_mm_fault+0x103/0x270
[  286.863807]  ? do_user_addr_fault+0x3f0/0x950
[  286.864781]  ? trace_page_fault_kernel+0x110/0x110
[  286.865862]  ? mark_held_locks+0x24/0x90
[  286.866777]  __x64_sys_sendto+0x6f/0x80
[  286.867621]  do_syscall_64+0x33/0x40
[  286.868504]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  286.869788] RIP: 0033:0x7f1279a1014a
[  286.870857] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f =

1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 =

<48> 3d 00 f0 ff ff 77 76 c3 0f 1f 44 00 00 55 48 83 ec 30 44 89 4c
[  286.875110] RSP: 002b:00007ffe1a791af8 EFLAGS: 00000246 ORIG_RAX: 000000=
000000002c
[  286.876758] RAX: ffffffffffffffda RBX: 00007ffe1a791b40 RCX: 00007f1279a=
1014a
[  286.878317] RDX: 0000000000000030 RSI: 00007ffe1a791b40 RDI: 00000000000=
00003
[  286.879885] RBP: 0000000000000030 R08: 00007ffe1a791b04 R09: 00000000000=
0000c
[  286.881537] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000=
00000
[  286.883189] R13: 0000000000000003 R14: 0000000000000000 R15: 00000000000=
00000


--
Mat Martineau
Intel
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