================================ WARNING: inconsistent lock state 6.12.0-rc1-syzkaller-00031-ge32cde8d2bd7 #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.0.157/5836 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88803285c9e0 (&pch->downl){+.?.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff88803285c9e0 (&pch->downl){+.?.}-{2:2}, at: ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ffff88803285c9e0 (&pch->downl){+.?.}-{2:2}, at: ppp_input+0x18b/0xa10 drivers/net/ppp/ppp_generic.c:2304 {SOFTIRQ-ON-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_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 irq event stamp: 2096 hardirqs last enabled at (2096): [] __local_bh_enable_ip+0x168/0x200 kernel/softirq.c:387 hardirqs last disabled at (2095): [] __local_bh_enable_ip+0x106/0x200 kernel/softirq.c:364 softirqs last enabled at (2062): [] pppoe_sendmsg+0xd5/0x750 drivers/net/ppp/pppoe.c:903 softirqs last disabled at (2075): [] __do_softirq kernel/softirq.c:588 [inline] softirqs last disabled at (2075): [] invoke_softirq kernel/softirq.c:428 [inline] softirqs last disabled at (2075): [] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&pch->downl); lock(&pch->downl); *** DEADLOCK *** 6 locks held by syz.0.157/5836: #0: ffff88805058c418 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #0: ffff88805058c418 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6099 [inline] #0: ffff88805058c418 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6159 #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: blk_cgroup_congested+0x1b/0x200 block/blk-cgroup.c:2191 #2: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #2: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x33b/0x15b0 net/core/dev.c:6103 #3: ffff8880505ff1d8 (slock-AF_PPPOX){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #3: ffff8880505ff1d8 (slock-AF_PPPOX){+.-.}-{2:2}, at: __sk_receive_skb+0x18c/0x8b0 net/core/sock.c:563 #4: ffff8880505ff258 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: __netif_receive_skb_one_core net/core/dev.c:5662 [inline] #4: ffff8880505ff258 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: __netif_receive_skb+0x2e0/0x650 net/core/dev.c:5775 #5: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #5: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #5: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2267 [inline] #5: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: ppp_input+0x55/0xa10 drivers/net/ppp/ppp_generic.c:2304 stack backtrace: CPU: 0 UID: 0 PID: 5836 Comm: syz.0.157 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+0xbf9/0x2050 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] __sk_receive_skb+0x82b/0x8b0 net/core/sock.c:570 __netif_receive_skb_one_core net/core/dev.c:5662 [inline] __netif_receive_skb+0x2e0/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6107 __napi_poll+0xcb/0x490 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6962 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 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_is_held_type+0x13b/0x190 Code: 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 42 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0000:ffffc9001727f028 EFLAGS: 00000206 RAX: c64236f5a2248400 RBX: 0000000000000000 RCX: 0000000080000000 RDX: ffff8880507c1e00 RSI: ffffffff8c0adc40 RDI: ffffffff8c602460 RBP: 0000000000000002 R08: ffffffff849d2a09 R09: 1ffffffff2852100 R10: dffffc0000000000 R11: fffffbfff2852101 R12: 0000000000000246 R13: ffff8880507c1e00 R14: 00000000ffffffff R15: ffffffff8e96c4e8 lock_is_held include/linux/lockdep.h:249 [inline] task_css include/linux/cgroup.h:434 [inline] blkcg_css+0xa2/0x1d0 block/blk-cgroup.c:110 blk_cgroup_congested+0xbb/0x200 block/blk-cgroup.c:2192 __folio_throttle_swaprate+0x84/0x1d0 mm/swapfile.c:3990 folio_throttle_swaprate include/linux/swap.h:645 [inline] folio_prealloc+0x10a/0x170 mm/memory.c:1074 wp_page_copy mm/memory.c:3353 [inline] do_wp_page+0x11c4/0x52d0 mm/memory.c:3745 handle_pte_fault+0x10e3/0x6800 mm/memory.c:5767 __handle_mm_fault mm/memory.c:5894 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6062 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:__put_user_4+0x11/0x20 arch/x86/lib/putuser.S:88 Code: 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 cb 48 c1 fb 3f 48 09 d9 0f 01 cb <89> 01 31 c9 0f 01 ca c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 RSP: 0000:ffffc9001727f9d8 EFLAGS: 00050202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000020002038 RDX: 0000000020002000 RSI: ffffffff8c0adc40 RDI: ffffffff8c602460 RBP: ffffc9001727fed0 R08: ffffffff901bba2f R09: 1ffffffff2037745 R10: dffffc0000000000 R11: fffffbfff2037746 R12: 1ffff92002e4ff48 R13: dffffc0000000000 R14: 000000000000000e R15: 0000000000000026 __sys_sendmmsg+0x50e/0x730 net/socket.c:2747 __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: 0033:0x7f7592d7dff9 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:00007f7593b6a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f7592f35f80 RCX: 00007f7592d7dff9 RDX: 0400000000000026 RSI: 0000000020001cc0 RDI: 0000000000000004 RBP: 00007f7592df0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7592f35f80 R15: 00007fff3560b918 ---------------- Code disassembly (best guess): 0: 75 44 jne 0x46 2: 48 c7 04 24 00 00 00 movq $0x0,(%rsp) 9: 00 a: 9c pushf b: 8f 04 24 pop (%rsp) e: f7 04 24 00 02 00 00 testl $0x200,(%rsp) 15: 75 4c jne 0x63 17: 41 f7 c4 00 02 00 00 test $0x200,%r12d 1e: 74 01 je 0x21 20: fb sti 21: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 28: 00 00 * 2a: 48 3b 44 24 08 cmp 0x8(%rsp),%rax <-- trapping instruction 2f: 75 42 jne 0x73 31: 89 d8 mov %ebx,%eax 33: 48 83 c4 10 add $0x10,%rsp 37: 5b pop %rbx 38: 41 5c pop %r12 3a: 41 5d pop %r13 3c: 41 5e pop %r14 3e: 41 5f pop %r15