ci starts bisection 2023-06-16 10:26:27.651407833 +0000 UTC m=+20771.614247203
bisecting fixing commit since 60d86034b14eed902b3f2bea97d0c237cf2f9499
building syzkaller on 96166539c4c242fccd41c7316b7080377dca428b
ensuring issue is reproducible on original commit 60d86034b14eed902b3f2bea97d0c237cf2f9499
testing commit 60d86034b14eed902b3f2bea97d0c237cf2f9499 gcc
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: f3acdf0b1b49f61d25afb27dcef6a0488d8aa9e210507b3118a5cbed55e087ae
all runs: crashed: possible deadlock in br_multicast_rcv
testing current HEAD c08afcdcf95288c627267bb20002e8baaf3394e1
testing commit c08afcdcf95288c627267bb20002e8baaf3394e1 gcc
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
kernel signature: 1551170a38091aee6c079b0ef535a3afc25f86c6a937e57b1d0a354dcd028a23
all runs: crashed: possible deadlock in br_multicast_rcv
crash still not fixed/happens on the oldest tested release
revisions tested: 2, total time: 25m31.88680802s (build: 17m40.070200206s, test: 6m35.537278105s)
crash still not fixed on HEAD or HEAD had kernel test errors
commit msg: sfc: do not try to call tc functions when CONFIG_SFC_SRIOV=n
crash: possible deadlock in br_multicast_rcv
============================================
WARNING: possible recursive locking detected
6.4.0-rc6-syzkaller #0 Not tainted
--------------------------------------------
syz-executor.0/5715 is trying to acquire lock:
ffff88807efd5330 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline]
ffff88807efd5330 (&br->multicast_lock){+.-.}-{2:2}, at: br_ip4_multicast_query net/bridge/br_multicast.c:3435 [inline]
ffff88807efd5330 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_ipv4_rcv net/bridge/br_multicast.c:3849 [inline]
ffff88807efd5330 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_rcv+0xaa4/0x5e40 net/bridge/br_multicast.c:3965
but task is already holding lock:
ffff88807efd1330 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline]
ffff88807efd1330 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_port_query_expired+0x5d/0x2c0 net/bridge/br_multicast.c:1900
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&br->multicast_lock);
lock(&br->multicast_lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
7 locks held by syz-executor.0/5715:
#0: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: cgroup_sk_alloc+0x4/0x750 kernel/cgroup/cgroup.c:6946
#1: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: rcu_read_unlock include/linux/rcupdate.h:807 [inline]
#1: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: percpu_ref_get_many include/linux/percpu-refcount.h:209 [inline]
#1: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: percpu_ref_get include/linux/percpu-refcount.h:222 [inline]
#1: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: css_get include/linux/cgroup_refcnt.h:11 [inline]
#1: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: cgroup_get include/linux/cgroup.h:353 [inline]
#1: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: cgroup_sk_alloc+0x41b/0x750 kernel/cgroup/cgroup.c:6953
#2: ffffc900001e0d78 ((&pmctx->ip4_own_query.timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:31 [inline]
#2: ffffc900001e0d78 ((&pmctx->ip4_own_query.timer)){+.-.}-{0:0}, at: call_timer_fn+0xcd/0x400 kernel/time/timer.c:1690
#3: ffff88807efd1330 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline]
#3: ffff88807efd1330 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_port_query_expired+0x5d/0x2c0 net/bridge/br_multicast.c:1900
#4: ffffffff8b78fa60 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1fd/0x2ff0 net/core/dev.c:4120
#5: ffffffff8b78fa60 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1fd/0x2ff0 net/core/dev.c:4120
#6: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
#6: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: br_tc_skb_miss_set net/bridge/br_private.h:763 [inline]
#6: ffffffff8b78fac0 (rcu_read_lock){....}-{1:2}, at: br_dev_xmit+0xd3/0x1370 net/bridge/br_device.c:42
stack backtrace:
CPU: 1 PID: 5715 Comm: syz-executor.0 Not tainted 6.4.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x64/0xb0 lib/dump_stack.c:106
print_deadlock_bug kernel/locking/lockdep.c:3006 [inline]
check_deadlock kernel/locking/lockdep.c:3049 [inline]
validate_chain kernel/locking/lockdep.c:3834 [inline]
__lock_acquire+0x13eb/0x5f30 kernel/locking/lockdep.c:5088
lock_acquire kernel/locking/lockdep.c:5705 [inline]
lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5670
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:350 [inline]
br_ip4_multicast_query net/bridge/br_multicast.c:3435 [inline]
br_multicast_ipv4_rcv net/bridge/br_multicast.c:3849 [inline]
br_multicast_rcv+0xaa4/0x5e40 net/bridge/br_multicast.c:3965
br_dev_xmit+0x610/0x1370 net/bridge/br_device.c:90
__netdev_start_xmit include/linux/netdevice.h:4910 [inline]
netdev_start_xmit include/linux/netdevice.h:4924 [inline]
xmit_one net/core/dev.c:3537 [inline]
dev_hard_start_xmit+0x153/0x580 net/core/dev.c:3553
__dev_queue_xmit+0x2316/0x2ff0 net/core/dev.c:4203
dev_queue_xmit include/linux/netdevice.h:3088 [inline]
vlan_dev_hard_start_xmit+0x32a/0x540 net/8021q/vlan_dev.c:125
__netdev_start_xmit include/linux/netdevice.h:4910 [inline]
netdev_start_xmit include/linux/netdevice.h:4924 [inline]
xmit_one net/core/dev.c:3537 [inline]
dev_hard_start_xmit+0x153/0x580 net/core/dev.c:3553
__dev_queue_xmit+0x2316/0x2ff0 net/core/dev.c:4203
dev_queue_xmit include/linux/netdevice.h:3088 [inline]
br_dev_queue_push_xmit+0x1df/0x670 net/bridge/br_forward.c:53
NF_HOOK include/linux/netfilter.h:303 [inline]
__br_multicast_send_query+0x23cb/0x43c0 net/bridge/br_multicast.c:1804
br_multicast_send_query+0x1ef/0x3e0 net/bridge/br_multicast.c:1883
br_multicast_port_query_expired+0x22b/0x2c0 net/bridge/br_multicast.c:1908
call_timer_fn+0x163/0x400 kernel/time/timer.c:1700
expire_timers+0x224/0x400 kernel/time/timer.c:1751
__run_timers kernel/time/timer.c:2022 [inline]
__run_timers kernel/time/timer.c:1995 [inline]
run_timer_softirq+0x296/0x790 kernel/time/timer.c:2035
__do_softirq+0x1d4/0x905 kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x114/0x190 kernel/softirq.c:650
irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1106
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:rcu_preempt_read_exit kernel/rcu/tree_plugin.h:382 [inline]
RIP: 0010:__rcu_read_unlock+0x2d/0x570 kernel/rcu/tree_plugin.h:421
Code: fa 41 56 41 55 41 54 55 65 48 8b 2c 25 c0 ba 03 00 53 48 8d bd 3c 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 24
RSP: 0018:ffffc90004ee7ce0 EFLAGS: 00000a07
RAX: dffffc0000000000 RBX: ffff88801f133488 RCX: ffffffff81718c3b
RDX: 1ffff11003b45baf RSI: ffffffff89c2a2c0 RDI: ffff88801da2dd7c
RBP: ffff88801da2d940 R08: 0000000000000000 R09: ffffffff903c3c47
R10: fffffbfff2078788 R11: ffff88807bd2e888 R12: ffffed1003b45d8f
R13: ffff88807bd2e800 R14: ffff88801da2d940 R15: ffff88807ec1a000
rcu_read_unlock+0xe/0x60 include/linux/rcupdate.h:805
percpu_ref_tryget_many include/linux/percpu-refcount.h:250 [inline]
percpu_ref_tryget include/linux/percpu-refcount.h:266 [inline]
css_tryget include/linux/cgroup_refcnt.h:45 [inline]
cgroup_tryget include/linux/cgroup.h:358 [inline]
cgroup_sk_alloc+0x486/0x750 kernel/cgroup/cgroup.c:6961
sk_alloc+0x25d/0x650 net/core/sock.c:2159
__netlink_create+0x58/0x360 net/netlink/af_netlink.c:649
netlink_create+0x309/0x550 net/netlink/af_netlink.c:712
__sock_create+0x241/0x610 net/socket.c:1535
sock_create net/socket.c:1586 [inline]
__sys_socket_create net/socket.c:1623 [inline]
__sys_socket_create net/socket.c:1608 [inline]
__sys_socket+0x113/0x1c0 net/socket.c:1651
__do_sys_socket net/socket.c:1664 [inline]
__se_sys_socket net/socket.c:1662 [inline]
__x64_sys_socket+0x6e/0xb0 net/socket.c:1662
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f47de28c0c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f47defdc168 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f47de3abf80 RCX: 00007f47de28c0c9
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000010
RBP: 00007f47de2e7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffe3e0b03f R14: 00007f47defdc300 R15: 0000000000022000
----------------
Code disassembly (best guess):
0: fa cli
1: 41 56 push %r14
3: 41 55 push %r13
5: 41 54 push %r12
7: 55 push %rbp
8: 65 48 8b 2c 25 c0 ba mov %gs:0x3bac0,%rbp
f: 03 00
11: 53 push %rbx
12: 48 8d bd 3c 04 00 00 lea 0x43c(%rbp),%rdi
19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
20: fc ff df
23: 48 89 fa mov %rdi,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx <-- trapping instruction
2e: 48 89 f8 mov %rdi,%rax
31: 83 e0 07 and $0x7,%eax
34: 83 c0 03 add $0x3,%eax
37: 38 d0 cmp %dl,%al
39: 7c 08 jl 0x43
3b: 84 d2 test %dl,%dl
3d: 0f .byte 0xf
3e: 85 .byte 0x85
3f: 24 .byte 0x24