INFO: task hung in rtnetlink_rcv_msg

INFO: task hung in rtnetlink_rcv_msg

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    64c0133eb88a Merge tag 'armsoc-fixes' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14976800c00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ee434566c893c7b1
dashboard link: https://syzkaller.appspot.com/bug?extid=8218a8a0ff60c19b8eae
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11c8a14cc00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1189db74c00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+8218a8a0ff60c19b8eae@syzkaller.appspotmail.com

INFO: task syz-executor725:8005 blocked for more than 140 seconds.
       Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D27984  8005   7591 0x00000004
Call Trace:
  context_switch kernel/sched/core.c:2844 [inline]
  __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
  schedule+0x92/0x180 kernel/sched/core.c:3529
  schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
  __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
  __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
  mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
  rtnl_lock net/core/rtnetlink.c:77 [inline]
  rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
  netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
  rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
  netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
  netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
  netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg+0xdd/0x130 net/socket.c:631
  ___sys_sendmsg+0x806/0x930 net/socket.c:2114
  __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg net/socket.c:2159 [inline]
  __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac037 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor725:8008 blocked for more than 140 seconds.
       Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D27552  8008   7590 0x00000004
Call Trace:
  context_switch kernel/sched/core.c:2844 [inline]
  __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
  schedule+0x92/0x180 kernel/sched/core.c:3529
  schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
  __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
  __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
  mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
  rtnl_lock net/core/rtnetlink.c:77 [inline]
  rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
  netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
  rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
  netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
  netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
  netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg+0xdd/0x130 net/socket.c:631
  ___sys_sendmsg+0x806/0x930 net/socket.c:2114
  __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg net/socket.c:2159 [inline]
  __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac03d R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor725:8009 blocked for more than 140 seconds.
       Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D28008  8009   7595 0x00000004
Call Trace:
  context_switch kernel/sched/core.c:2844 [inline]
  __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
  schedule+0x92/0x180 kernel/sched/core.c:3529
  schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
  __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
  __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
  mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
  rtnl_lock net/core/rtnetlink.c:77 [inline]
  rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
  netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
  rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
  netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
  netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
  netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg+0xdd/0x130 net/socket.c:631
  ___sys_sendmsg+0x806/0x930 net/socket.c:2114
  __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg net/socket.c:2159 [inline]
  __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac03d R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor725:8010 blocked for more than 140 seconds.
       Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D28000  8010   7596 0x00000004
Call Trace:
  context_switch kernel/sched/core.c:2844 [inline]
  __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
  schedule+0x92/0x180 kernel/sched/core.c:3529
  schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
  __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
  __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
  mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
  rtnl_lock net/core/rtnetlink.c:77 [inline]
  rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
  netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
  rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
  netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
  netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
  netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg+0xdd/0x130 net/socket.c:631
  ___sys_sendmsg+0x806/0x930 net/socket.c:2114
  __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg net/socket.c:2159 [inline]
  __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac03e R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor725:8011 blocked for more than 140 seconds.
       Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D28008  8011   7594 0x00000004
Call Trace:
  context_switch kernel/sched/core.c:2844 [inline]
  __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
  schedule+0x92/0x180 kernel/sched/core.c:3529
  schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
  __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
  __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
  mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
  rtnl_lock net/core/rtnetlink.c:77 [inline]
  rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
  netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
  rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
  netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
  netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
  netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg+0xdd/0x130 net/socket.c:631
  ___sys_sendmsg+0x806/0x930 net/socket.c:2114
  __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg net/socket.c:2159 [inline]
  __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a  
fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac03b R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000

Showing all locks held in the system:
3 locks held by kworker/1:1/22:
  #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:  
__write_once_size include/linux/compiler.h:220 [inline]
  #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:  
arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
  #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:  
atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
  #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:  
atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
  #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:  
set_work_data kernel/workqueue.c:617 [inline]
  #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:  
set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
  #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:  
process_one_work+0x87e/0x1790 kernel/workqueue.c:2144
  #1: 00000000e8391065 ((addr_chk_work).work){+.+.}, at:  
process_one_work+0x8b4/0x1790 kernel/workqueue.c:2148
  #2: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20  
net/core/rtnetlink.c:77
1 lock held by khungtaskd/1040:
  #0: 00000000083344d4 (rcu_read_lock){....}, at:  
debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4389
1 lock held by rsyslogd/7472:
  #0: 000000007562dcc1 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110  
fs/file.c:795
2 locks held by getty/7562:
  #0: 000000000837ceb2 (&tty->ldisc_sem){++++}, at:  
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
  #1: 00000000d91e6e17 (&ldata->atomic_read_lock){+.+.}, at:  
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7563:
  #0: 00000000243db696 (&tty->ldisc_sem){++++}, at:  
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
  #1: 000000000002034d (&ldata->atomic_read_lock){+.+.}, at:  
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7564:
  #0: 00000000a59e483b (&tty->ldisc_sem){++++}, at:  
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
  #1: 000000004032d53a (&ldata->atomic_read_lock){+.+.}, at:  
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7565:
  #0: 0000000025343c97 (&tty->ldisc_sem){++++}, at:  
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
  #1: 00000000727bf19a (&ldata->atomic_read_lock){+.+.}, at:  
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7566:
  #0: 000000003dac20af (&tty->ldisc_sem){++++}, at:  
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
  #1: 00000000fef38c44 (&ldata->atomic_read_lock){+.+.}, at:  
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7567:
  #0: 00000000da1bfc9c (&tty->ldisc_sem){++++}, at:  
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
  #1: 00000000f82cf636 (&ldata->atomic_read_lock){+.+.}, at:  
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7568:
  #0: 00000000a5d9fcdf (&tty->ldisc_sem){++++}, at:  
ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
  #1: 000000005ae165cb (&ldata->atomic_read_lock){+.+.}, at:  
n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
1 lock held by syz-executor725/8002:
1 lock held by syz-executor725/8005:
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock  
net/core/rtnetlink.c:77 [inline]
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00  
net/core/rtnetlink.c:5127
1 lock held by syz-executor725/8008:
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock  
net/core/rtnetlink.c:77 [inline]
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00  
net/core/rtnetlink.c:5127
1 lock held by syz-executor725/8009:
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock  
net/core/rtnetlink.c:77 [inline]
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00  
net/core/rtnetlink.c:5127
1 lock held by syz-executor725/8010:
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock  
net/core/rtnetlink.c:77 [inline]
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00  
net/core/rtnetlink.c:5127
1 lock held by syz-executor725/8011:
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock  
net/core/rtnetlink.c:77 [inline]
  #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00  
net/core/rtnetlink.c:5127

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1040 Comm: khungtaskd Not tainted 5.0.0-rc6+ #75
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x172/0x1f0 lib/dump_stack.c:113
  nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
  nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62
  arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
  trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
  check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
  watchdog+0x9df/0xee0 kernel/hung_task.c:287
  kthread+0x357/0x430 kernel/kthread.c:246
  ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.415  
msecs
NMI backtrace for cpu 1
CPU: 1 PID: 8002 Comm: syz-executor725 Not tainted 5.0.0-rc6+ #75
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:unwind_next_frame.part.0+0x1a8/0x9a0  
arch/x86/kernel/unwind_frame.c:329
Code: 8b 6d 20 4c 89 ee 48 89 df 4c 89 95 60 ff ff ff 4c 89 9d 68 ff ff ff  
4c 89 8d 70 ff ff ff e8 6f f7 ff ff 4c 8b 8d 70 ff ff ff <41> 89 c0 4c 8b  
9d 68 ff ff ff b8 01 00 00 00 45 84 c0 4c 8b 95 60
RSP: 0018:ffff888096136e28 EFLAGS: 00000286
RAX: 0000000000000001 RBX: ffff888096136f00 RCX: 1ffff11012c26de8
RDX: dffffc0000000000 RSI: 1ffff11012c26d00 RDI: ffff888096136f48
RBP: ffff888096136ed8 R08: 0000000000000001 R09: ffff888096136f50
R10: ffff888096136f28 R11: ffff888096136f38 R12: 1ffff11012c26dca
R13: ffff888096137b70 R14: ffff888096137b40 R15: ffff888096137f58
FS:  00000000024b2880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 000000009810b000 CR4: 00000000001406e0
Call Trace:
  unwind_next_frame+0x3b/0x50 arch/x86/kernel/unwind_frame.c:287
  __save_stack_trace+0x7a/0xf0 arch/x86/kernel/stacktrace.c:44
  save_stack_trace+0x1a/0x20 arch/x86/kernel/stacktrace.c:60
  save_stack+0x45/0xd0 mm/kasan/common.c:73
  set_track mm/kasan/common.c:85 [inline]
  __kasan_kmalloc mm/kasan/common.c:496 [inline]
  __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
  kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504
  __do_kmalloc_node mm/slab.c:3673 [inline]
  __kmalloc_node_track_caller+0x4e/0x70 mm/slab.c:3687
  __kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:140
  pskb_expand_head+0x14e/0xdd0 net/core/skbuff.c:1465
  netlink_trim+0x215/0x270 net/netlink/af_netlink.c:1292
  netlink_unicast+0xbf/0x720 net/netlink/af_netlink.c:1326
  rtnetlink_send+0xf0/0x110 net/core/rtnetlink.c:721
  tcf_add_notify net/sched/act_api.c:1325 [inline]
  tcf_action_add+0x243/0x370 net/sched/act_api.c:1344
  tc_ctl_action+0x3b6/0x4bd net/sched/act_api.c:1392
  rtnetlink_rcv_msg+0x465/0xb00 net/core/rtnetlink.c:5130
  netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
  rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
  netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
  netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
  netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:621 [inline]
  sock_sendmsg+0xdd/0x130 net/socket.c:631
  ___sys_sendmsg+0x806/0x930 net/socket.c:2114
  __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
  __do_sys_sendmsg net/socket.c:2161 [inline]
  __se_sys_sendmsg net/socket.c:2159 [inline]
  __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7  
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff  
ff 0f 83 0b 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac031 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000


---
This bug is generated by a bot. It may contain errors.
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Re: INFO: task hung in rtnetlink_rcv_msg

[Jakub Kicinski]

Hi!

Seems like something funny is going on with get_maintainer.pl since XDP
entry got added.  We seem to have been CCed on:

net: ns83820: code cleanup for ns83820_probe_phy()
veth: Fix -Wformat-truncation
INFO: task hung in rtnetlink_rcv_msg

I tried Florian's veth patch myself and it does indeed produce:

"David S. Miller" <davem@davemloft.net> (odd fixer:NETWORKING DRIVERS,commit_signer:9/15=60%)
Alexei Starovoitov <ast@kernel.org> (supporter:XDP (eXpress Data Path))
Daniel Borkmann <daniel@iogearbox.net> (supporter:XDP (eXpress Data Path),commit_signer:6/15=40%)
Jakub Kicinski <jakub.kicinski@netronome.com> (supporter:XDP (eXpress Data Path))
Jesper Dangaard Brouer <hawk@kernel.org> (supporter:XDP (eXpress Data Path))
John Fastabend <john.fastabend@gmail.com> (supporter:XDP (eXpress Data Path),commit_signer:2/15=13%)
Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> (commit_signer:11/15=73%,authored:11/15=73%,added_lines:1027/1055=97%,removed_lines:180/195=92%)
David Ahern <dsahern@gmail.com> (commit_signer:2/15=13%,authored:1/15=7%)
Li RongQing <lirongqing@baidu.com> (authored:1/15=7%,removed_lines:14/195=7%)
Michael Walle <michael@walle.cc> (authored:1/15=7%)
"Gustavo A. R. Silva" <gustavo@embeddedor.com> (authored:1/15=7%)
netdev@vger.kernel.org (open list:NETWORKING DRIVERS)
linux-kernel@vger.kernel.org (open list)
xdp-newbies@vger.kernel.org (open list:XDP (eXpress Data Path))

Even though it only touches:

 drivers/net/veth.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

And XDP entry is:

XDP (eXpress Data Path)
M:	Alexei Starovoitov <ast@kernel.org>
M:	Daniel Borkmann <daniel@iogearbox.net>
M:	David S. Miller <davem@davemloft.net>
M:	Jakub Kicinski <jakub.kicinski@netronome.com>
M:	Jesper Dangaard Brouer <hawk@kernel.org>
M:	John Fastabend <john.fastabend@gmail.com>
L:	netdev@vger.kernel.org
L:	xdp-newbies@vger.kernel.org
S:	Supported
F:	net/core/xdp.c
F:	include/net/xdp.h
F:	kernel/bpf/devmap.c
F:	kernel/bpf/cpumap.c
F:	include/trace/events/xdp.h
K:	xdp
N:	xdp

So no relation to drivers at all... 

Re: INFO: task hung in rtnetlink_rcv_msg

[Joe Perches]

On Fri, 2019-02-22 at 12:01 -0800, Jakub Kicinski wrote:
> Hi!
> 
> Seems like something funny is going on with get_maintainer.pl since XDP
> entry got added.  We seem to have been CCed on:

I suggest removing the MAINTAINERS line with

	K:	xdp

as xdp is a pretty generic file/patch content
regex match for the K: type

$ git grep --name-only xdp | wc -l
236

Rather more files than desired.

The N: match is dubious too.

It's generally better to have specific lists of
maintained file patterns rather than using the
K: and N: pattern matches.

---
 MAINTAINERS | 1 -
 1 file changed, 1 deletion(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index d7ad97b235ec..aa703e2cb882 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16970,7 +16970,6 @@ F:	include/net/xdp.h
 F:	kernel/bpf/devmap.c
 F:	kernel/bpf/cpumap.c
 F:	include/trace/events/xdp.h
-K:	xdp
 N:	xdp
 
 XDP SOCKETS (AF_XDP)

Re: INFO: task hung in rtnetlink_rcv_msg

[Jakub Kicinski]

On Fri, 22 Feb 2019 12:14:57 -0800, Joe Perches wrote:
> On Fri, 2019-02-22 at 12:01 -0800, Jakub Kicinski wrote:
> > Hi!
> > 
> > Seems like something funny is going on with get_maintainer.pl since XDP
> > entry got added.  We seem to have been CCed on:  
> 
> I suggest removing the MAINTAINERS line with
> 
> 	K:	xdp
> 
> as xdp is a pretty generic file/patch content
> regex match for the K: type
> 
> $ git grep --name-only xdp | wc -l
> 236
> 
> Rather more files than desired.
> 
> The N: match is dubious too.
> 
> It's generally better to have specific lists of
> maintained file patterns rather than using the
> K: and N: pattern matches.
> 
> ---
>  MAINTAINERS | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index d7ad97b235ec..aa703e2cb882 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -16970,7 +16970,6 @@ F:	include/net/xdp.h
>  F:	kernel/bpf/devmap.c
>  F:	kernel/bpf/cpumap.c
>  F:	include/trace/events/xdp.h
> -K:	xdp
>  N:	xdp
>  
>  XDP SOCKETS (AF_XDP)

Thanks for the explanation, at least now I know why it happens! :)
I'll leave it to Daniel to decide if we really need it removed, 
so far the false positives weren't overwhelming, just surprising.

Re: INFO: task hung in rtnetlink_rcv_msg

[Daniel Borkmann]

On 02/22/2019 10:45 PM, Jakub Kicinski wrote:
> On Fri, 22 Feb 2019 12:14:57 -0800, Joe Perches wrote:
>> On Fri, 2019-02-22 at 12:01 -0800, Jakub Kicinski wrote:
>>> Hi!
>>>
>>> Seems like something funny is going on with get_maintainer.pl since XDP
>>> entry got added.  We seem to have been CCed on:  
>>
>> I suggest removing the MAINTAINERS line with
>>
>> 	K:	xdp
>>
>> as xdp is a pretty generic file/patch content
>> regex match for the K: type
>>
>> $ git grep --name-only xdp | wc -l
>> 236
>>
>> Rather more files than desired.
>>
>> The N: match is dubious too.
>>
>> It's generally better to have specific lists of
>> maintained file patterns rather than using the
>> K: and N: pattern matches.
>>
>> ---
>>  MAINTAINERS | 1 -
>>  1 file changed, 1 deletion(-)
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index d7ad97b235ec..aa703e2cb882 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -16970,7 +16970,6 @@ F:	include/net/xdp.h
>>  F:	kernel/bpf/devmap.c
>>  F:	kernel/bpf/cpumap.c
>>  F:	include/trace/events/xdp.h
>> -K:	xdp
>>  N:	xdp
>>  
>>  XDP SOCKETS (AF_XDP)
> 
> Thanks for the explanation, at least now I know why it happens! :)
> I'll leave it to Daniel to decide if we really need it removed, 
> so far the false positives weren't overwhelming, just surprising.

No strong opinion. I've seen this K+N pattern in a number of places
in the maintainers file. I'm fine either way if it gets too noisy. :)

Re: INFO: task hung in rtnetlink_rcv_msg

[Jesper Dangaard Brouer]

On Sat, 23 Feb 2019 01:47:00 +0100
Daniel Borkmann <daniel@iogearbox.net> wrote:

> On 02/22/2019 10:45 PM, Jakub Kicinski wrote:
> > On Fri, 22 Feb 2019 12:14:57 -0800, Joe Perches wrote:  
> >> On Fri, 2019-02-22 at 12:01 -0800, Jakub Kicinski wrote:  
> >>> Hi!
> >>>
> >>> Seems like something funny is going on with get_maintainer.pl since XDP
> >>> entry got added.  We seem to have been CCed on:    
> >>
> >> I suggest removing the MAINTAINERS line with
> >>
> >> 	K:	xdp
> >>
> >> as xdp is a pretty generic file/patch content
> >> regex match for the K: type
> >>
> >> $ git grep --name-only xdp | wc -l
> >> 236

I'm unsure how K: works, but you grep definitely selects some wrong files.

I tried with "xdp_":
 git grep --name-only xdp_

That does catch all the driver that have XDP support, which is the
point of the exercise (to catch drivers).

It does contain a couple of false-positives:
  drivers/net/ethernet/neterion/vxge/vxge-traffic.c
  drivers/thunderbolt/tb_msgs.h
  drivers/thunderbolt/xdomain.c
  sound/soc/codecs/rt5670.c

Via the pattern '[^a-z]xdp_' I'm only left with the thunderbolt
false-positive, as it have a data struct's called tb_xdp_*.




> >> Rather more files than desired.
> >>
> >> The N: match is dubious too.
> >>
> >> It's generally better to have specific lists of
> >> maintained file patterns rather than using the
> >> K: and N: pattern matches.
> >>
> >> ---
> >>  MAINTAINERS | 1 -
> >>  1 file changed, 1 deletion(-)
> >>
> >> diff --git a/MAINTAINERS b/MAINTAINERS
> >> index d7ad97b235ec..aa703e2cb882 100644
> >> --- a/MAINTAINERS
> >> +++ b/MAINTAINERS
> >> @@ -16970,7 +16970,6 @@ F:	include/net/xdp.h
> >>  F:	kernel/bpf/devmap.c
> >>  F:	kernel/bpf/cpumap.c
> >>  F:	include/trace/events/xdp.h
> >> -K:	xdp
> >>  N:	xdp
> >>  
> >>  XDP SOCKETS (AF_XDP)  
> > 
> > Thanks for the explanation, at least now I know why it happens! :)
> > I'll leave it to Daniel to decide if we really need it removed, 
> > so far the false positives weren't overwhelming, just surprising.  
> 
> No strong opinion. I've seen this K+N pattern in a number of places
> in the maintainers file. I'm fine either way if it gets too noisy. :)



-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer

Re: INFO: task hung in rtnetlink_rcv_msg

[Joe Perches]

On Mon, 2019-02-25 at 09:39 +0100, Jesper Dangaard Brouer wrote:
> On Sat, 23 Feb 2019 01:47:00 +0100
> Daniel Borkmann <daniel@iogearbox.net> wrote:
> 
> > On 02/22/2019 10:45 PM, Jakub Kicinski wrote:
> > > On Fri, 22 Feb 2019 12:14:57 -0800, Joe Perches wrote:  
> > > > On Fri, 2019-02-22 at 12:01 -0800, Jakub Kicinski wrote:  
> > > > > Hi!
> > > > > 
> > > > > Seems like something funny is going on with get_maintainer.pl since XDP
> > > > > entry got added.  We seem to have been CCed on:    
> > > > 
> > > > I suggest removing the MAINTAINERS line with
> > > > 
> > > > 	K:	xdp
> > > > 
> > > > as xdp is a pretty generic file/patch content
> > > > regex match for the K: type
> > > > 
> > > > $ git grep --name-only xdp | wc -l
> > > > 236
> 
> I'm unsure how K: works, but you grep definitely selects some wrong files.
> 
> I tried with "xdp_":
>  git grep --name-only xdp_
> 
> That does catch all the driver that have XDP support, which is the
> point of the exercise (to catch drivers).
> 
> It does contain a couple of false-positives:
>   drivers/net/ethernet/neterion/vxge/vxge-traffic.c
>   drivers/thunderbolt/tb_msgs.h
>   drivers/thunderbolt/xdomain.c
>   sound/soc/codecs/rt5670.c
> 
> Via the pattern '[^a-z]xdp_' I'm only left with the thunderbolt
> false-positive, as it have a data struct's called tb_xdp_*.

Then it's probably better to use

K:	\Wxdp_

and if XDP_ is also to be matched, maybe

K:	(?i:\Wxdp_)

Re: INFO: task hung in rtnetlink_rcv_msg

[Jesper Dangaard Brouer]

On Mon, 25 Feb 2019 08:55:40 -0800
Joe Perches <joe@perches.com> wrote:

> On Mon, 2019-02-25 at 09:39 +0100, Jesper Dangaard Brouer wrote:
> > On Sat, 23 Feb 2019 01:47:00 +0100
> > Daniel Borkmann <daniel@iogearbox.net> wrote:
> >   
> > > On 02/22/2019 10:45 PM, Jakub Kicinski wrote:  
> > > > On Fri, 22 Feb 2019 12:14:57 -0800, Joe Perches wrote:    
> > > > > On Fri, 2019-02-22 at 12:01 -0800, Jakub Kicinski wrote:    
> > > > > > Hi!
> > > > > > 
> > > > > > Seems like something funny is going on with get_maintainer.pl since XDP
> > > > > > entry got added.  We seem to have been CCed on:      
> > > > > 
> > > > > I suggest removing the MAINTAINERS line with
> > > > > 
> > > > > 	K:	xdp
> > > > > 
> > > > > as xdp is a pretty generic file/patch content
> > > > > regex match for the K: type
> > > > > 
> > > > > $ git grep --name-only xdp | wc -l
> > > > > 236  
> > 
> > I'm unsure how K: works, but you grep definitely selects some wrong files.
> > 
> > I tried with "xdp_":
> >  git grep --name-only xdp_
> > 
> > That does catch all the driver that have XDP support, which is the
> > point of the exercise (to catch drivers).
> > 
> > It does contain a couple of false-positives:
> >   drivers/net/ethernet/neterion/vxge/vxge-traffic.c
> >   drivers/thunderbolt/tb_msgs.h
> >   drivers/thunderbolt/xdomain.c
> >   sound/soc/codecs/rt5670.c
> > 
> > Via the pattern '[^a-z]xdp_' I'm only left with the thunderbolt
> > false-positive, as it have a data struct's called tb_xdp_*.  
> 
> Then it's probably better to use
> 
> K:	\Wxdp_
> 
> and if XDP_ is also to be matched, maybe
> 
> K:	(?i:\Wxdp_)
> 

The last one seems to be the best at matching the relevant files :-)

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer