raw-gadget.0 gadget.2: fail, usb_ep_enable returned -22 ===================================================== WARNING: SOFTIRQ-READ-safe -> SOFTIRQ-READ-unsafe lock order detected 6.11.0-syzkaller-08833-gde5cb0dcb74c #0 Not tainted ----------------------------------------------------- syz.2.1261/12524 [HC0[0]:SC0[4]:HE1:SE0] is trying to acquire: ffff888067226e10 (&ppp->rlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888067226e10 (&ppp->rlock){+...}-{2:2}, at: ppp_ioctl+0x15f8/0x1cd0 drivers/net/ppp/ppp_generic.c:823 and this task is already holding: ffff888067226e50 (&ppp->wlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888067226e50 (&ppp->wlock){+...}-{2:2}, at: ppp_ioctl+0x15e7/0x1cd0 drivers/net/ppp/ppp_generic.c:823 which would create a new lock dependency: (&ppp->wlock){+...}-{2:2} -> (&ppp->rlock){+...}-{2:2} but this new dependency connects a SOFTIRQ-READ-irq-safe lock: (&pch->upl){++.-}-{2:2} ... which became SOFTIRQ-READ-irq-safe at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3d/0x50 kernel/locking/spinlock.c:252 ppp_input_error+0x60/0x1b0 drivers/net/ppp/ppp_generic.c:2344 ppp_sync_process+0x82/0x160 drivers/net/ppp/ppp_synctty.c:486 tasklet_action_common+0x321/0x4d0 kernel/softirq.c:784 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 to a SOFTIRQ-READ-irq-unsafe lock: (&pch->downl){+.+.}-{2:2} ... which became SOFTIRQ-READ-irq-unsafe at: ... lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __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:351 [inline] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ppp_input+0x18b/0xa10 drivers/net/ppp/ppp_generic.c:2304 pppoe_rcv_core+0x117/0x310 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1113 [inline] __release_sock+0x243/0x350 net/core/sock.c:3072 release_sock+0x61/0x1f0 net/core/sock.c:3626 pppoe_sendmsg+0xd5/0x750 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2603 ___sys_sendmsg net/socket.c:2657 [inline] __sys_sendmmsg+0x3ac/0x730 net/socket.c:2743 __do_sys_sendmmsg net/socket.c:2772 [inline] __se_sys_sendmmsg net/socket.c:2769 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2769 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f 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 *** 2 locks held by syz.2.1261/12524: #0: ffffffff8f4b30e8 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0x112/0x1cd0 drivers/net/ppp/ppp_generic.c:729 #1: ffff888067226e50 (&ppp->wlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff888067226e50 (&ppp->wlock){+...}-{2:2}, at: ppp_ioctl+0x15e7/0x1cd0 drivers/net/ppp/ppp_generic.c:823 the dependencies between SOFTIRQ-READ-irq-safe lock and the holding lock: -> (&pch->upl){++.-}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x35/0x50 kernel/locking/spinlock.c:334 ppp_connect_channel+0x87/0x650 drivers/net/ppp/ppp_generic.c:3478 ppp_ioctl+0xdd4/0x1cd0 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f HARDIRQ-ON-R at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3d/0x50 kernel/locking/spinlock.c:252 ppp_channel_push+0x2c/0x220 drivers/net/ppp/ppp_generic.c:2186 ppp_write+0x2b0/0x3e0 drivers/net/ppp/ppp_generic.c:540 vfs_write+0x29c/0xc90 fs/read_write.c:681 ksys_write+0x1a0/0x2c0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f IN-SOFTIRQ-R at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3d/0x50 kernel/locking/spinlock.c:252 ppp_input_error+0x60/0x1b0 drivers/net/ppp/ppp_generic.c:2344 ppp_sync_process+0x82/0x160 drivers/net/ppp/ppp_synctty.c:486 tasklet_action_common+0x321/0x4d0 kernel/softirq.c:784 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x35/0x50 kernel/locking/spinlock.c:334 ppp_connect_channel+0x87/0x650 drivers/net/ppp/ppp_generic.c:3478 ppp_ioctl+0xdd4/0x1cd0 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3d/0x50 kernel/locking/spinlock.c:252 ppp_channel_push+0x2c/0x220 drivers/net/ppp/ppp_generic.c:2186 ppp_write+0x2b0/0x3e0 drivers/net/ppp/ppp_generic.c:540 vfs_write+0x29c/0xc90 fs/read_write.c:681 ksys_write+0x1a0/0x2c0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] ppp_register_net_channel.__key.3+0x0/0x20 -> (&ppp->wlock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_get_stats64+0xc3/0x290 drivers/net/ppp/ppp_generic.c:1539 dev_get_stats+0xad/0xa00 net/core/dev.c:10937 rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1268 rtnl_fill_ifinfo+0x18da/0x2270 net/core/rtnetlink.c:1909 rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4079 rtmsg_ifinfo_event net/core/rtnetlink.c:4112 [inline] rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4121 register_netdevice+0x1774/0x1b00 net/core/dev.c:10534 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline] ppp_dev_configure+0x883/0xb10 drivers/net/ppp/ppp_generic.c:1275 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x797/0x1cd0 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_get_stats64+0xc3/0x290 drivers/net/ppp/ppp_generic.c:1539 dev_get_stats+0xad/0xa00 net/core/dev.c:10937 rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1268 rtnl_fill_ifinfo+0x18da/0x2270 net/core/rtnetlink.c:1909 rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4079 rtmsg_ifinfo_event net/core/rtnetlink.c:4112 [inline] rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4121 register_netdevice+0x1774/0x1b00 net/core/dev.c:10534 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline] ppp_dev_configure+0x883/0xb10 drivers/net/ppp/ppp_generic.c:1275 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x797/0x1cd0 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] ppp_dev_configure.__key.67+0x0/0x20 ... acquired at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_connect_channel+0x174/0x650 drivers/net/ppp/ppp_generic.c:3484 ppp_ioctl+0xdd4/0x1cd0 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f the dependencies between the lock to be acquired and SOFTIRQ-READ-irq-unsafe lock: -> (&pch->downl){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_connect_channel+0x194/0x650 drivers/net/ppp/ppp_generic.c:3485 ppp_ioctl+0xdd4/0x1cd0 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f SOFTIRQ-ON-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __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:351 [inline] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ppp_input+0x18b/0xa10 drivers/net/ppp/ppp_generic.c:2304 pppoe_rcv_core+0x117/0x310 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1113 [inline] __release_sock+0x243/0x350 net/core/sock.c:3072 release_sock+0x61/0x1f0 net/core/sock.c:3626 pppoe_sendmsg+0xd5/0x750 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2603 ___sys_sendmsg net/socket.c:2657 [inline] __sys_sendmmsg+0x3ac/0x730 net/socket.c:2743 __do_sys_sendmmsg net/socket.c:2772 [inline] __se_sys_sendmmsg net/socket.c:2769 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2769 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_connect_channel+0x194/0x650 drivers/net/ppp/ppp_generic.c:3485 ppp_ioctl+0xdd4/0x1cd0 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] ppp_register_net_channel.__key.1+0x0/0x20 ... acquired at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_connect_channel+0x194/0x650 drivers/net/ppp/ppp_generic.c:3485 ppp_ioctl+0xdd4/0x1cd0 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&ppp->rlock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_get_stats64+0x33/0x290 drivers/net/ppp/ppp_generic.c:1534 dev_get_stats+0xad/0xa00 net/core/dev.c:10937 rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1268 rtnl_fill_ifinfo+0x18da/0x2270 net/core/rtnetlink.c:1909 rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4079 rtmsg_ifinfo_event net/core/rtnetlink.c:4112 [inline] rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4121 register_netdevice+0x1774/0x1b00 net/core/dev.c:10534 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline] ppp_dev_configure+0x883/0xb10 drivers/net/ppp/ppp_generic.c:1275 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x797/0x1cd0 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_get_stats64+0x33/0x290 drivers/net/ppp/ppp_generic.c:1534 dev_get_stats+0xad/0xa00 net/core/dev.c:10937 rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1268 rtnl_fill_ifinfo+0x18da/0x2270 net/core/rtnetlink.c:1909 rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4079 rtmsg_ifinfo_event net/core/rtnetlink.c:4112 [inline] rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4121 register_netdevice+0x1774/0x1b00 net/core/dev.c:10534 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline] ppp_dev_configure+0x883/0xb10 drivers/net/ppp/ppp_generic.c:1275 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x797/0x1cd0 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] ppp_dev_configure.__key+0x0/0x20 ... acquired at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_ioctl+0x15f8/0x1cd0 drivers/net/ppp/ppp_generic.c:823 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f stack backtrace: CPU: 0 UID: 0 PID: 12524 Comm: syz.2.1261 Not tainted 6.11.0-syzkaller-08833-gde5cb0dcb74c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2644 [inline] check_irq_usage kernel/locking/lockdep.c:2885 [inline] check_prev_add kernel/locking/lockdep.c:3162 [inline] check_prevs_add kernel/locking/lockdep.c:3277 [inline] validate_chain+0x4ebd/0x5920 kernel/locking/lockdep.c:3901 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_ioctl+0x15f8/0x1cd0 drivers/net/ppp/ppp_generic.c:823 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f390f97def9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f391069e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f390fb35f80 RCX: 00007f390f97def9 RDX: 00000000200000c0 RSI: 0000000040047459 RDI: 0000000000000004 RBP: 00007f390f9f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f390fb35f80 R15: 00007f390fc5fa28