========================================================
WARNING: possible irq lock inversion dependency detected
6.1.111-syzkaller #0 Not tainted
--------------------------------------------------------
ksoftirqd/1/21 just changed the state of lock:
ffff88805c2f0dd0 (&ppp->rlock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88805c2f0dd0 (&ppp->rlock){+.-.}-{2:2}, at: ppp_do_recv+0x38/0x26a0 drivers/net/ppp/ppp_generic.c:2210
but this lock took another, SOFTIRQ-unsafe lock in the past:
(&pch->downl){+.+.}-{2:2}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&pch->downl);
local_irq_disable();
lock(&ppp->rlock);
lock(&pch->downl);
<Interrupt>
lock(&ppp->rlock);
*** DEADLOCK ***
4 locks held by ksoftirqd/1/21:
#0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x2c9/0x760 net/core/dev.c:5969
#1: ffff88805c7990b0 (slock-AF_PPPOX){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#1: ffff88805c7990b0 (slock-AF_PPPOX){+.-.}-{2:2}, at: __sk_receive_skb+0x188/0x9d0 net/core/sock.c:562
#2: ffff88805c799130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: __netif_receive_skb_one_core net/core/dev.c:5528 [inline]
#2: ffff88805c799130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5642
#3: ffff888026f3e248 (&pch->upl){++.-}-{2:2}, at: ppp_input+0x3ca/0xa00 drivers/net/ppp/ppp_generic.c:2307
the shortest dependencies between 2nd lock and 1st lock:
-> (&pch->downl){+.+.}-{2:2} {
HARDIRQ-ON-W at:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
__ppp_channel_push+0x31/0x1d0 drivers/net/ppp/ppp_generic.c:2161
ppp_channel_push+0x196/0x220 drivers/net/ppp/ppp_generic.c:2192
ppp_write+0x294/0x3a0 drivers/net/ppp/ppp_generic.c:538
do_iter_write+0x503/0xc40 fs/read_write.c:863
vfs_writev fs/read_write.c:934 [inline]
do_pwritev+0x216/0x360 fs/read_write.c:1031
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
SOFTIRQ-ON-W
at:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline]
ppp_input+0x185/0xa00 drivers/net/ppp/ppp_generic.c:2304
pppoe_rcv_core+0x112/0x300 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv include/net/sock.h:1117 [inline]
__release_sock+0x198/0x4b0 net/core/sock.c:2936
release_sock+0x5d/0x1c0 net/core/sock.c:3500
pppoe_sendmsg+0xd1/0x740 drivers/net/ppp/pppoe.c:903
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5a5/0x8f0 net/socket.c:2514
___sys_sendmsg net/socket.c:2568 [inline]
__sys_sendmmsg+0x3ab/0x730 net/socket.c:2654
__do_sys_sendmmsg net/socket.c:2683 [inline]
__se_sys_sendmmsg net/socket.c:2680 [inline]
__x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2680
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
INITIAL USE at:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
__ppp_channel_push+0x31/0x1d0 drivers/net/ppp/ppp_generic.c:2161
ppp_channel_push+0x196/0x220 drivers/net/ppp/ppp_generic.c:2192
ppp_write+0x294/0x3a0 drivers/net/ppp/ppp_generic.c:538
do_iter_write+0x503/0xc40 fs/read_write.c:863
vfs_writev fs/read_write.c:934 [inline]
do_pwritev+0x216/0x360 fs/read_write.c:1031
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
}
... key at: [<ffffffff976db040>] ppp_register_net_channel.__key.1+0x0/0x20
... acquired at:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
ppp_connect_channel+0x190/0x640 drivers/net/ppp/ppp_generic.c:3485
ppp_ioctl+0xbe5/0x1c90 drivers/net/ppp/ppp_generic.c:759
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> (&ppp->rlock){+.-.}-{2:2} {
HARDIRQ-ON-W at:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
ppp_get_stats64+0x2f/0x290 drivers/net/ppp/ppp_generic.c:1534
dev_get_stats+0xa7/0x490 net/core/dev.c:10471
rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1244
rtnl_fill_ifinfo+0x18aa/0x2090 net/core/rtnetlink.c:1825
rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3938
rtmsg_ifinfo_event net/core/rtnetlink.c:3970 [inline]
rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3979
register_netdevice+0x13dc/0x1720 net/core/dev.c:10146
ppp_unit_register drivers/net/ppp/ppp_generic.c:1217 [inline]
ppp_dev_configure+0x850/0xab0 drivers/net/ppp/ppp_generic.c:1273
ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline]
ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1058 [inline]
ppp_ioctl+0x702/0x1c90 drivers/net/ppp/ppp_generic.c:731
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
IN-SOFTIRQ-W at:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
ppp_do_recv+0x38/0x26a0 drivers/net/ppp/ppp_generic.c:2210
ppp_input+0x5cc/0xa00 drivers/net/ppp/ppp_generic.c:2327
pppoe_rcv_core+0x112/0x300 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv include/net/sock.h:1117 [inline]
__sk_receive_skb+0x41a/0x9d0 net/core/sock.c:569
__netif_receive_skb_one_core net/core/dev.c:5528 [inline]
__netif_receive_skb+0x1c6/0x530 net/core/dev.c:5642
process_backlog+0x381/0x760 net/core/dev.c:5970
__napi_poll+0xc7/0x470 net/core/dev.c:6537
napi_poll net/core/dev.c:6604 [inline]
net_rx_action+0x70f/0xeb0 net/core/dev.c:6718
handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
run_ksoftirqd+0xc6/0x120 kernel/softirq.c:938
smpboot_thread_fn+0x52c/0xa30 kernel/smpboot.c:164
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
INITIAL USE at:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
ppp_get_stats64+0x2f/0x290 drivers/net/ppp/ppp_generic.c:1534
dev_get_stats+0xa7/0x490 net/core/dev.c:10471
rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1244
rtnl_fill_ifinfo+0x18aa/0x2090 net/core/rtnetlink.c:1825
rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3938
rtmsg_ifinfo_event net/core/rtnetlink.c:3970 [inline]
rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3979
register_netdevice+0x13dc/0x1720 net/core/dev.c:10146
ppp_unit_register drivers/net/ppp/ppp_generic.c:1217 [inline]
ppp_dev_configure+0x850/0xab0 drivers/net/ppp/ppp_generic.c:1273
ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline]
ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1058 [inline]
ppp_ioctl+0x702/0x1c90 drivers/net/ppp/ppp_generic.c:731
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
}
... key at: [<ffffffff976db180>] ppp_dev_configure.__key+0x0/0x20
... acquired at:
mark_lock+0x21c/0x340 kernel/locking/lockdep.c:4628
__lock_acquire+0xb7f/0x1f80 kernel/locking/lockdep.c:5003
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
ppp_do_recv+0x38/0x26a0 drivers/net/ppp/ppp_generic.c:2210
ppp_input+0x5cc/0xa00 drivers/net/ppp/ppp_generic.c:2327
pppoe_rcv_core+0x112/0x300 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv include/net/sock.h:1117 [inline]
__sk_receive_skb+0x41a/0x9d0 net/core/sock.c:569
__netif_receive_skb_one_core net/core/dev.c:5528 [inline]
__netif_receive_skb+0x1c6/0x530 net/core/dev.c:5642
process_backlog+0x381/0x760 net/core/dev.c:5970
__napi_poll+0xc7/0x470 net/core/dev.c:6537
napi_poll net/core/dev.c:6604 [inline]
net_rx_action+0x70f/0xeb0 net/core/dev.c:6718
handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
run_ksoftirqd+0xc6/0x120 kernel/softirq.c:938
smpboot_thread_fn+0x52c/0xa30 kernel/smpboot.c:164
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
stack backtrace:
CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 6.1.111-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
mark_lock_irq+0x7de/0xba0 kernel/locking/lockdep.c:4199
mark_lock+0x21c/0x340 kernel/locking/lockdep.c:4628
__lock_acquire+0xb7f/0x1f80 kernel/locking/lockdep.c:5003
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
ppp_do_recv+0x38/0x26a0 drivers/net/ppp/ppp_generic.c:2210
ppp_input+0x5cc/0xa00 drivers/net/ppp/ppp_generic.c:2327
pppoe_rcv_core+0x112/0x300 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv include/net/sock.h:1117 [inline]
__sk_receive_skb+0x41a/0x9d0 net/core/sock.c:569
__netif_receive_skb_one_core net/core/dev.c:5528 [inline]
__netif_receive_skb+0x1c6/0x530 net/core/dev.c:5642
process_backlog+0x381/0x760 net/core/dev.c:5970
__napi_poll+0xc7/0x470 net/core/dev.c:6537
napi_poll net/core/dev.c:6604 [inline]
net_rx_action+0x70f/0xeb0 net/core/dev.c:6718
handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
run_ksoftirqd+0xc6/0x120 kernel/softirq.c:938
smpboot_thread_fn+0x52c/0xa30 kernel/smpboot.c:164
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>