======================================================== WARNING: possible irq lock inversion dependency detected 5.15.167-syzkaller #0 Not tainted -------------------------------------------------------- ksoftirqd/1/20 just changed the state of lock: ffff888077c35a40 (&pch->upl){+..-}-{2:2}, at: ppp_input+0x361/0x980 drivers/net/ppp/ppp_generic.c:2306 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: Chain exists of: &pch->upl --> &ppp->wlock --> &pch->downl Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pch->downl); local_irq_disable(); lock(&pch->upl); lock(&ppp->wlock); lock(&pch->upl); *** DEADLOCK *** no locks held by ksoftirqd/1/20. the shortest dependencies between 2nd lock and 1st lock: -> (&pch->downl){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_connect_channel+0x190/0x640 drivers/net/ppp/ppp_generic.c:3484 ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 SOFTIRQ-ON-W at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2271 [inline] ppp_input+0x160/0x980 drivers/net/ppp/ppp_generic.c:2303 pppoe_rcv_core+0x109/0x2f0 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1059 [inline] __release_sock+0x198/0x4b0 net/core/sock.c:2724 release_sock+0x5d/0x1c0 net/core/sock.c:3265 pppoe_sendmsg+0xd1/0x740 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2485 __sys_sendmmsg+0x2bf/0x560 net/socket.c:2571 __do_sys_sendmmsg net/socket.c:2600 [inline] __se_sys_sendmmsg net/socket.c:2597 [inline] __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2597 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 INITIAL USE at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_connect_channel+0x190/0x640 drivers/net/ppp/ppp_generic.c:3484 ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 } ... key at: [] ppp_register_net_channel.__key.1+0x0/0x20 ... acquired at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_connect_channel+0x190/0x640 drivers/net/ppp/ppp_generic.c:3484 ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> ( &ppp->rlock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_get_stats64+0x2f/0x290 drivers/net/ppp/ppp_generic.c:1533 dev_get_stats+0x90/0x370 net/core/dev.c:10704 rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1205 rtnl_fill_ifinfo+0x1598/0x1d60 net/core/rtnetlink.c:1782 rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3856 rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline] rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3897 register_netdevice+0x13d2/0x1720 net/core/dev.c:10402 ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline] ppp_dev_configure+0x853/0xad0 drivers/net/ppp/ppp_generic.c:1272 ppp_create_interface drivers/net/ppp/ppp_generic.c:3347 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1057 [inline] ppp_ioctl+0x702/0x1cd0 drivers/net/ppp/ppp_generic.c:730 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 INITIAL USE at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_get_stats64+0x2f/0x290 drivers/net/ppp/ppp_generic.c:1533 dev_get_stats+0x90/0x370 net/core/dev.c:10704 rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1205 rtnl_fill_ifinfo+0x1598/0x1d60 net/core/rtnetlink.c:1782 rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3856 rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline] rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3897 register_netdevice+0x13d2/0x1720 net/core/dev.c:10402 ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline] ppp_dev_configure+0x853/0xad0 drivers/net/ppp/ppp_generic.c:1272 ppp_create_interface drivers/net/ppp/ppp_generic.c:3347 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1057 [inline] ppp_ioctl+0x702/0x1cd0 drivers/net/ppp/ppp_generic.c:730 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 } ... key at: [] ppp_dev_configure.__key+0x0/0x20 ... acquired at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_connect_channel+0x181/0x640 drivers/net/ppp/ppp_generic.c:3483 ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> (&ppp->wlock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_get_stats64+0xbf/0x290 drivers/net/ppp/ppp_generic.c:1538 dev_get_stats+0x90/0x370 net/core/dev.c:10704 rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1205 rtnl_fill_ifinfo+0x1598/0x1d60 net/core/rtnetlink.c:1782 rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3856 rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline] rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3897 register_netdevice+0x13d2/0x1720 net/core/dev.c:10402 ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline] ppp_dev_configure+0x853/0xad0 drivers/net/ppp/ppp_generic.c:1272 ppp_create_interface drivers/net/ppp/ppp_generic.c:3347 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1057 [inline] ppp_ioctl+0x702/0x1cd0 drivers/net/ppp/ppp_generic.c:730 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 INITIAL USE at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_get_stats64+0xbf/0x290 drivers/net/ppp/ppp_generic.c:1538 dev_get_stats+0x90/0x370 net/core/dev.c:10704 rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1205 rtnl_fill_ifinfo+0x1598/0x1d60 net/core/rtnetlink.c:1782 rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3856 rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline] rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3897 register_netdevice+0x13d2/0x1720 net/core/dev.c:10402 ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline] ppp_dev_configure+0x853/0xad0 drivers/net/ppp/ppp_generic.c:1272 ppp_create_interface drivers/net/ppp/ppp_generic.c:3347 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1057 [inline] ppp_ioctl+0x702/0x1cd0 drivers/net/ppp/ppp_generic.c:730 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 } ... key at: [] ppp_dev_configure.__key.62+0x0/0x20 ... acquired at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_connect_channel+0x170/0x640 drivers/net/ppp/ppp_generic.c:3483 ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> (&pch->upl ){+..-}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline] _raw_write_lock_bh+0x31/0x40 kernel/locking/spinlock.c:324 ppp_connect_channel+0x87/0x640 drivers/net/ppp/ppp_generic.c:3477 ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 IN-SOFTIRQ-R at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x39/0x50 kernel/locking/spinlock.c:252 ppp_input+0x361/0x980 drivers/net/ppp/ppp_generic.c:2306 ppp_sync_process+0x75/0x170 drivers/net/ppp/ppp_synctty.c:501 tasklet_action_common+0x3cb/0x4a0 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 INITIAL USE at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline] _raw_write_lock_bh+0x31/0x40 kernel/locking/spinlock.c:324 ppp_connect_channel+0x87/0x640 drivers/net/ppp/ppp_generic.c:3477 ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 } ... key at: [] ppp_register_net_channel.__key.3+0x0/0x20 ... acquired at: mark_lock+0x21a/0x340 kernel/locking/lockdep.c:4591 __lock_acquire+0xb9d/0x1ff0 kernel/locking/lockdep.c:4966 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x39/0x50 kernel/locking/spinlock.c:252 ppp_input+0x361/0x980 drivers/net/ppp/ppp_generic.c:2306 ppp_sync_process+0x75/0x170 drivers/net/ppp/ppp_synctty.c:501 tasklet_action_common+0x3cb/0x4a0 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 stack backtrace: CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 mark_lock_irq+0x7d8/0xba0 kernel/locking/lockdep.c:4162 mark_lock+0x21a/0x340 kernel/locking/lockdep.c:4591 __lock_acquire+0xb9d/0x1ff0 kernel/locking/lockdep.c:4966 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x39/0x50 kernel/locking/spinlock.c:252 ppp_input+0x361/0x980 drivers/net/ppp/ppp_generic.c:2306 ppp_sync_process+0x75/0x170 drivers/net/ppp/ppp_synctty.c:501 tasklet_action_common+0x3cb/0x4a0 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:925 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287