syzbot has found a reproducer for the following issue on: HEAD commit: eb0f1697d729 Merge branch 'for-next/core', remote-tracking.. git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=17733b4d280000 kernel config: https://syzkaller.appspot.com/x/.config?x=8860074b9a9d6c45 dashboard link: https://syzkaller.appspot.com/bug?extid=ece2915262061d6e0ac1 compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 userspace arch: arm64 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15b4e536280000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10224d6d280000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/034232da7cff/disk-eb0f1697.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/b11411bec33e/vmlinux-eb0f1697.xz kernel image: https://storage.googleapis.com/syzbot-assets/a53c52e170dd/Image-eb0f1697.gz.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/2ce9b06770e0/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ece2915262061d6e0ac1@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.4.0-rc3-syzkaller-geb0f1697d729 #0 Not tainted ------------------------------------------------------ klogd/5578 is trying to acquire lock: ffff0001fea76c40 (&pgdat->kcompactd_wait){-...}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:137 [inline] ffff0001fea76c40 (&pgdat->kcompactd_wait){-...}-{2:2}, at: __wake_up+0xec/0x1a8 kernel/sched/wait.c:160 but task is already holding lock: ffff0001b4259b18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:558 [inline] ffff0001b4259b18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1366 [inline] ffff0001b4259b18 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1653 [inline] ffff0001b4259b18 (&rq->__lock){-.-.}-{2:2}, at: scheduler_tick+0xa4/0x52c kernel/sched/core.c:5616 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x50/0x6c kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2c/0x44 kernel/sched/core.c:558 raw_spin_rq_lock kernel/sched/sched.h:1366 [inline] rq_lock kernel/sched/sched.h:1653 [inline] task_fork_fair+0x7c/0x23c kernel/sched/fair.c:12095 sched_cgroup_fork+0x38c/0x464 kernel/sched/core.c:4777 copy_process+0x24fc/0x3514 kernel/fork.c:2618 kernel_clone+0x1d8/0x8ac kernel/fork.c:2918 user_mode_thread+0x110/0x178 kernel/fork.c:2996 rest_init+0x2c/0x2f4 init/main.c:700 start_kernel+0x0/0x55c init/main.c:834 start_kernel+0x3f0/0x55c init/main.c:1088 __primary_switched+0xb8/0xc0 arch/arm64/kernel/head.S:523 -> #1 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162 try_to_wake_up+0xb0/0xd9c kernel/sched/core.c:4191 default_wake_function+0x4c/0x60 kernel/sched/core.c:6993 autoremove_wake_function+0x24/0xf8 kernel/sched/wait.c:419 __wake_up_common+0x23c/0x3bc kernel/sched/wait.c:107 __wake_up_common_lock kernel/sched/wait.c:138 [inline] __wake_up+0x10c/0x1a8 kernel/sched/wait.c:160 wakeup_kcompactd+0x254/0x310 mm/compaction.c:2942 balance_pgdat+0x1880/0x1c34 mm/vmscan.c:7541 kswapd+0x7d0/0x10fc mm/vmscan.c:7738 kthread+0x288/0x310 kernel/kthread.c:379 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:853 -> #0 (&pgdat->kcompactd_wait){-...}-{2:2}: check_prev_add kernel/locking/lockdep.c:3108 [inline] check_prevs_add kernel/locking/lockdep.c:3227 [inline] validate_chain kernel/locking/lockdep.c:3842 [inline] __lock_acquire+0x3310/0x75f0 kernel/locking/lockdep.c:5074 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5691 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162 __wake_up_common_lock kernel/sched/wait.c:137 [inline] __wake_up+0xec/0x1a8 kernel/sched/wait.c:160 wakeup_kcompactd+0x254/0x310 mm/compaction.c:2942 wakeup_kswapd+0x350/0x8c8 mm/vmscan.c:7792 wake_all_kswapds+0x13c/0x23c mm/page_alloc.c:4028 __alloc_pages_slowpath+0x378/0x1edc mm/page_alloc.c:4296 __alloc_pages+0x3bc/0x698 mm/page_alloc.c:4781 alloc_pages+0x4bc/0x7c0 __stack_depot_save+0x4ac/0x678 lib/stackdepot.c:410 kasan_save_stack+0x54/0x6c mm/kasan/common.c:46 __kasan_record_aux_stack+0xcc/0xe8 mm/kasan/generic.c:491 kasan_record_aux_stack+0x14/0x20 mm/kasan/generic.c:496 task_work_add+0x94/0x3c0 kernel/task_work.c:48 task_tick_mm_cid kernel/sched/core.c:11940 [inline] scheduler_tick+0x2d0/0x52c kernel/sched/core.c:5626 update_process_times+0x198/0x1f4 kernel/time/timer.c:2076 tick_sched_handle kernel/time/tick-sched.c:243 [inline] tick_sched_timer+0x330/0x4e8 kernel/time/tick-sched.c:1481 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x458/0xca0 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x2c0/0xb64 kernel/time/hrtimer.c:1811 timer_handler drivers/clocksource/arm_arch_timer.c:656 [inline] arch_timer_handler_virt+0x74/0x88 drivers/clocksource/arm_arch_timer.c:667 handle_percpu_devid_irq+0x2a4/0x804 kernel/irq/chip.c:930 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq_desc kernel/irq/irqdesc.c:651 [inline] generic_handle_domain_irq+0x7c/0xc4 kernel/irq/irqdesc.c:707 __gic_handle_irq drivers/irqchip/irq-gic-v3.c:728 [inline] __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:779 [inline] gic_handle_irq+0x70/0x1e4 drivers/irqchip/irq-gic-v3.c:823 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:882 do_interrupt_handler+0xd4/0x138 arch/arm64/kernel/entry-common.c:274 __el1_irq arch/arm64/kernel/entry-common.c:471 [inline] el1_interrupt+0x34/0x68 arch/arm64/kernel/entry-common.c:486 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:587 __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:182 [inline] arch_local_irq_restore arch/arm64/include/asm/irqflags.h:202 [inline] dump_stack_lvl+0x104/0x124 lib/dump_stack.c:107 dump_stack+0x1c/0x28 lib/dump_stack.c:113 dump_header+0xb4/0x954 mm/oom_kill.c:460 oom_kill_process+0x10c/0x6ec mm/oom_kill.c:1036 out_of_memory+0xe24/0x103c mm/oom_kill.c:1156 __alloc_pages_may_oom mm/page_alloc.c:3669 [inline] __alloc_pages_slowpath+0x1714/0x1edc mm/page_alloc.c:4444 __alloc_pages+0x3bc/0x698 mm/page_alloc.c:4781 alloc_pages+0x4bc/0x7c0 alloc_slab_page+0xa0/0x164 mm/slub.c:1851 allocate_slab mm/slub.c:2006 [inline] new_slab+0x210/0x2f4 mm/slub.c:2051 ___slab_alloc+0x80c/0xdf4 mm/slub.c:3192 __slab_alloc mm/slub.c:3291 [inline] __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] kmem_cache_alloc_node+0x318/0x46c mm/slub.c:3496 __alloc_skb+0x19c/0x3d8 net/core/skbuff.c:644 alloc_skb include/linux/skbuff.h:1288 [inline] alloc_skb_with_frags+0xb4/0x590 net/core/skbuff.c:6378 sock_alloc_send_pskb+0x76c/0x884 net/core/sock.c:2729 unix_dgram_sendmsg+0x480/0x16c0 net/unix/af_unix.c:1944 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] __sys_sendto+0x3b4/0x538 net/socket.c:2144 __do_sys_sendto net/socket.c:2156 [inline] __se_sys_sendto net/socket.c:2152 [inline] __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2152 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x4c/0x15c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 other info that might help us debug this: Chain exists of: &pgdat->kcompactd_wait --> &p->pi_lock --> &rq->__lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->__lock); lock(&p->pi_lock); lock(&rq->__lock); lock(&pgdat->kcompactd_wait); *** DEADLOCK *** 2 locks held by klogd/5578: #0: ffff8000161245e8 (oom_lock){+.+.}-{3:3}, at: __alloc_pages_may_oom mm/page_alloc.c:3618 [inline] #0: ffff8000161245e8 (oom_lock){+.+.}-{3:3}, at: __alloc_pages_slowpath+0x1694/0x1edc mm/page_alloc.c:4444 #1: ffff0001b4259b18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:558 [inline] #1: ffff0001b4259b18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1366 [inline] #1: ffff0001b4259b18 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1653 [inline] #1: ffff0001b4259b18 (&rq->__lock){-.-.}-{2:2}, at: scheduler_tick+0xa4/0x52c kernel/sched/core.c:5616 stack backtrace: CPU: 1 PID: 5578 Comm: klogd Not tainted 6.4.0-rc3-syzkaller-geb0f1697d729 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2066 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2188 check_prev_add kernel/locking/lockdep.c:3108 [inline] check_prevs_add kernel/locking/lockdep.c:3227 [inline] validate_chain kernel/locking/lockdep.c:3842 [inline] __lock_acquire+0x3310/0x75f0 kernel/locking/lockdep.c:5074 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5691 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162 __wake_up_common_lock kernel/sched/wait.c:137 [inline] __wake_up+0xec/0x1a8 kernel/sched/wait.c:160 wakeup_kcompactd+0x254/0x310 mm/compaction.c:2942 wakeup_kswapd+0x350/0x8c8 mm/vmscan.c:7792 wake_all_kswapds+0x13c/0x23c mm/page_alloc.c:4028 __alloc_pages_slowpath+0x378/0x1edc mm/page_alloc.c:4296 __alloc_pages+0x3bc/0x698 mm/page_alloc.c:4781 alloc_pages+0x4bc/0x7c0 __stack_depot_save+0x4ac/0x678 lib/stackdepot.c:410 kasan_save_stack+0x54/0x6c mm/kasan/common.c:46 __kasan_record_aux_stack+0xcc/0xe8 mm/kasan/generic.c:491 kasan_record_aux_stack+0x14/0x20 mm/kasan/generic.c:496 task_work_add+0x94/0x3c0 kernel/task_work.c:48 task_tick_mm_cid kernel/sched/core.c:11940 [inline] scheduler_tick+0x2d0/0x52c kernel/sched/core.c:5626 update_process_times+0x198/0x1f4 kernel/time/timer.c:2076 tick_sched_handle kernel/time/tick-sched.c:243 [inline] tick_sched_timer+0x330/0x4e8 kernel/time/tick-sched.c:1481 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x458/0xca0 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x2c0/0xb64 kernel/time/hrtimer.c:1811 timer_handler drivers/clocksource/arm_arch_timer.c:656 [inline] arch_timer_handler_virt+0x74/0x88 drivers/clocksource/arm_arch_timer.c:667 handle_percpu_devid_irq+0x2a4/0x804 kernel/irq/chip.c:930 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq_desc kernel/irq/irqdesc.c:651 [inline] generic_handle_domain_irq+0x7c/0xc4 kernel/irq/irqdesc.c:707 __gic_handle_irq drivers/irqchip/irq-gic-v3.c:728 [inline] __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:779 [inline] gic_handle_irq+0x70/0x1e4 drivers/irqchip/irq-gic-v3.c:823 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:882 do_interrupt_handler+0xd4/0x138 arch/arm64/kernel/entry-common.c:274 __el1_irq arch/arm64/kernel/entry-common.c:471 [inline] el1_interrupt+0x34/0x68 arch/arm64/kernel/entry-common.c:486 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:587 __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:182 [inline] arch_local_irq_restore arch/arm64/include/asm/irqflags.h:202 [inline] dump_stack_lvl+0x104/0x124 lib/dump_stack.c:107 dump_stack+0x1c/0x28 lib/dump_stack.c:113 dump_header+0xb4/0x954 mm/oom_kill.c:460 oom_kill_process+0x10c/0x6ec mm/oom_kill.c:1036 out_of_memory+0xe24/0x103c mm/oom_kill.c:1156 __alloc_pages_may_oom mm/page_alloc.c:3669 [inline] __alloc_pages_slowpath+0x1714/0x1edc mm/page_alloc.c:4444 __alloc_pages+0x3bc/0x698 mm/page_alloc.c:4781 alloc_pages+0x4bc/0x7c0 alloc_slab_page+0xa0/0x164 mm/slub.c:1851 allocate_slab mm/slub.c:2006 [inline] new_slab+0x210/0x2f4 mm/slub.c:2051 ___slab_alloc+0x80c/0xdf4 mm/slub.c:3192 __slab_alloc mm/slub.c:3291 [inline] __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] kmem_cache_alloc_node+0x318/0x46c mm/slub.c:3496 __alloc_skb+0x19c/0x3d8 net/core/skbuff.c:644 alloc_skb include/linux/skbuff.h:1288 [inline] alloc_skb_with_frags+0xb4/0x590 net/core/skbuff.c:6378 sock_alloc_send_pskb+0x76c/0x884 net/core/sock.c:2729 unix_dgram_sendmsg+0x480/0x16c0 net/unix/af_unix.c:1944 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] __sys_sendto+0x3b4/0x538 net/socket.c:2144 __do_sys_sendto net/socket.c:2156 [inline] __se_sys_sendto net/socket.c:2152 [inline] __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2152 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x4c/0x15c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing.
