================================ WARNING: inconsistent lock state 6.12.0-rc1-syzkaller-00031-ge32cde8d2bd7 #0 Not tainted -------------------------------- inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. syz.0.3696/24355 [HC0[0]:SC0[0]:HE1:SE1] takes: ffff8880500c21e0 (&pch->downl){+.?.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff8880500c21e0 (&pch->downl){+.?.}-{2:2}, at: ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ffff8880500c21e0 (&pch->downl){+.?.}-{2:2}, at: ppp_input+0x18b/0xa10 drivers/net/ppp/ppp_generic.c:2304 {IN-SOFTIRQ-W} state was registered at: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __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_push+0x31/0x1e0 drivers/net/ppp/ppp_generic.c:2161 ppp_channel_push+0x196/0x220 drivers/net/ppp/ppp_generic.c:2192 tasklet_action_common+0x321/0x4d0 kernel/softirq.c:784 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 common_interrupt+0xb9/0xd0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 lock_is_held_type+0x13b/0x190 xa_entry include/linux/xarray.h:1220 [inline] xas_descend lib/xarray.c:207 [inline] xas_load+0x478/0x5c0 lib/xarray.c:245 xa_load+0x1fc/0x350 lib/xarray.c:1477 memcg_list_lru_allocated mm/list_lru.c:475 [inline] memcg_list_lru_alloc+0x1b2/0xd00 mm/list_lru.c:489 __memcg_slab_post_alloc_hook+0x140/0x7e0 mm/memcontrol.c:2968 memcg_slab_post_alloc_hook mm/slub.c:2157 [inline] slab_post_alloc_hook mm/slub.c:4096 [inline] slab_alloc_node mm/slub.c:4135 [inline] kmem_cache_alloc_lru_noprof+0x1e6/0x2b0 mm/slub.c:4154 shmem_alloc_inode+0x28/0x40 mm/shmem.c:4769 alloc_inode fs/inode.c:263 [inline] new_inode_pseudo fs/inode.c:1102 [inline] new_inode+0x6e/0x310 fs/inode.c:1121 __shmem_get_inode mm/shmem.c:2806 [inline] shmem_get_inode+0x34a/0xd70 mm/shmem.c:2877 shmem_symlink+0x12a/0x6c0 mm/shmem.c:3809 vfs_symlink+0x137/0x2e0 fs/namei.c:4615 do_symlinkat+0x222/0x3a0 fs/namei.c:4641 __do_sys_symlinkat fs/namei.c:4657 [inline] __se_sys_symlinkat fs/namei.c:4654 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4654 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 irq event stamp: 517 hardirqs last enabled at (517): [] __local_bh_enable_ip+0x168/0x200 kernel/softirq.c:387 hardirqs last disabled at (515): [] __local_bh_enable_ip+0x106/0x200 kernel/softirq.c:364 softirqs last enabled at (516): [] spin_unlock_bh include/linux/spinlock.h:396 [inline] softirqs last enabled at (516): [] __release_sock+0x9a/0x350 net/core/sock.c:3065 softirqs last disabled at (514): [] spin_lock_bh include/linux/spinlock.h:356 [inline] softirqs last disabled at (514): [] release_sock+0x30/0x1f0 net/core/sock.c:3624 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&pch->downl); lock(&pch->downl); *** DEADLOCK *** 2 locks held by syz.0.3696/24355: #0: ffff88807baef258 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1609 [inline] #0: ffff88807baef258 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppoe_sendmsg+0x51/0x750 drivers/net/ppp/pppoe.c:849 #1: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #1: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2267 [inline] #1: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: ppp_input+0x55/0xa10 drivers/net/ppp/ppp_generic.c:2304 stack backtrace: CPU: 1 UID: 0 PID: 24355 Comm: syz.0.3696 Not tainted 6.12.0-rc1-syzkaller-00031-ge32cde8d2bd7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_usage_bug+0x62e/0x8b0 kernel/locking/lockdep.c:4038 valid_state+0x13a/0x1c0 kernel/locking/lockdep.c:4052 mark_lock_irq+0xbb/0xc20 kernel/locking/lockdep.c:4263 mark_lock+0x223/0x360 kernel/locking/lockdep.c:4725 __lock_acquire+0x11b0/0x2050 kernel/locking/lockdep.c:5156 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __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:729 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:744 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2602 ___sys_sendmsg net/socket.c:2656 [inline] __sys_sendmmsg+0x3ab/0x730 net/socket.c:2742 __do_sys_sendmmsg net/socket.c:2771 [inline] __se_sys_sendmmsg net/socket.c:2768 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2768 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: 0033:0x7f8074b7dff9 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:00007f807593b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f8074d35f80 RCX: 00007f8074b7dff9 RDX: 0400000000000026 RSI: 0000000020001cc0 RDI: 0000000000000005 RBP: 00007f8074bf0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8074d35f80 R15: 00007f8074e5fa28