====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc5-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.3/21938 is trying to acquire lock: ffff88813fffece0 (&pgdat->kswapd_wait){..-.}-{2:2}, at: __wake_up_common_lock+0x25/0x1e0 kernel/sched/wait.c:105 but task is already holding lock: ffff888030a651f8 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xcb/0xc10 kernel/bpf/lpm_trie.c:324 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&trie->lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 trie_delete_elem+0x96/0x6a0 kernel/bpf/lpm_trie.c:451 0xffffffffa0002355 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420 trace_tlb_flush+0x118/0x140 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x7cb/0xae0 context_switch kernel/sched/core.c:5393 [inline] __schedule+0x1066/0x4a00 kernel/sched/core.c:6746 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6925 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6949 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:12 unwind_next_frame+0x2124/0x2a00 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc+0x174/0x340 mm/slub.c:3852 kmem_cache_zalloc include/linux/slab.h:739 [inline] alloc_buffer_head+0x2d/0x2a0 fs/buffer.c:3001 folio_alloc_buffers+0x2da/0x840 fs/buffer.c:924 grow_dev_folio fs/buffer.c:1067 [inline] grow_buffers fs/buffer.c:1108 [inline] __getblk_slow fs/buffer.c:1134 [inline] bdev_getblk+0x305/0x610 fs/buffer.c:1429 __bread_gfp+0xac/0x430 fs/buffer.c:1474 sb_bread include/linux/buffer_head.h:321 [inline] bfs_find_entry+0x1c3/0x3f0 fs/bfs/dir.c:333 bfs_lookup+0x14b/0x270 fs/bfs/dir.c:137 __lookup_slow+0x28c/0x3f0 fs/namei.c:1692 lookup_slow+0x53/0x70 fs/namei.c:1709 walk_component+0x2e1/0x410 fs/namei.c:2004 lookup_last fs/namei.c:2461 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2485 filename_lookup+0x256/0x610 fs/namei.c:2514 user_path_at_empty+0x42/0x60 fs/namei.c:2921 user_path_at include/linux/namei.h:57 [inline] do_mount fs/namespace.c:3689 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount+0x29a/0x3c0 fs/namespace.c:3875 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 raw_spin_rq_lock kernel/sched/sched.h:1387 [inline] rq_lock kernel/sched/sched.h:1701 [inline] task_fork_fair+0x61/0x1e0 kernel/sched/fair.c:12635 sched_cgroup_fork+0x37c/0x410 kernel/sched/core.c:4845 copy_process+0x2217/0x3df0 kernel/fork.c:2499 kernel_clone+0x223/0x870 kernel/fork.c:2797 user_mode_thread+0x132/0x1a0 kernel/fork.c:2875 rest_init+0x23/0x300 init/main.c:704 start_kernel+0x47a/0x500 init/main.c:1081 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x99/0xa0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 -> #1 (&p->pi_lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:553 [inline] try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4262 autoremove_wake_function+0x16/0x110 kernel/sched/wait.c:384 __wake_up_common kernel/sched/wait.c:89 [inline] __wake_up_common_lock+0x130/0x1e0 kernel/sched/wait.c:106 rmqueue mm/page_alloc.c:2919 [inline] get_page_from_freelist+0x30f1/0x35b0 mm/page_alloc.c:3314 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 alloc_pages_mpol+0x3e8/0x680 mm/mempolicy.c:2264 alloc_pages mm/mempolicy.c:2335 [inline] folio_alloc+0x128/0x180 mm/mempolicy.c:2342 filemap_alloc_folio+0xdf/0x500 mm/filemap.c:984 __filemap_get_folio+0x41a/0xbb0 mm/filemap.c:1926 grow_dev_folio fs/buffer.c:1042 [inline] grow_buffers fs/buffer.c:1108 [inline] __getblk_slow fs/buffer.c:1134 [inline] bdev_getblk+0x234/0x610 fs/buffer.c:1429 __bread_gfp+0xac/0x430 fs/buffer.c:1474 sb_bread include/linux/buffer_head.h:321 [inline] bfs_find_entry+0x1c3/0x3f0 fs/bfs/dir.c:333 bfs_lookup+0x14b/0x270 fs/bfs/dir.c:137 __lookup_slow+0x28c/0x3f0 fs/namei.c:1692 lookup_slow+0x53/0x70 fs/namei.c:1709 walk_component+0x2e1/0x410 fs/namei.c:2004 lookup_last fs/namei.c:2461 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2485 filename_lookup+0x256/0x610 fs/namei.c:2514 user_path_at_empty+0x42/0x60 fs/namei.c:2921 user_path_at include/linux/namei.h:57 [inline] do_mount fs/namespace.c:3689 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount+0x29a/0x3c0 fs/namespace.c:3875 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&pgdat->kswapd_wait){..-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 __wake_up_common_lock+0x25/0x1e0 kernel/sched/wait.c:105 rmqueue mm/page_alloc.c:2919 [inline] get_page_from_freelist+0x30f1/0x35b0 mm/page_alloc.c:3314 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] __kmalloc_large_node+0x91/0x1f0 mm/slub.c:3911 __do_kmalloc_node mm/slub.c:3954 [inline] __kmalloc_node+0x33e/0x4e0 mm/slub.c:3973 kmalloc_node include/linux/slab.h:648 [inline] bpf_map_kmalloc_node+0xd3/0x1c0 kernel/bpf/syscall.c:422 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:291 [inline] trie_update_elem+0x1d3/0xc10 kernel/bpf/lpm_trie.c:333 bpf_map_update_value+0x4d3/0x540 kernel/bpf/syscall.c:203 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5648 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &pgdat->kswapd_wait --> &rq->__lock --> &trie->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&trie->lock); lock(&rq->__lock); lock(&trie->lock); lock(&pgdat->kswapd_wait); *** DEADLOCK *** 2 locks held by syz-executor.3/21938: #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: bpf_map_update_value+0x3c4/0x540 kernel/bpf/syscall.c:202 #1: ffff888030a651f8 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xcb/0xc10 kernel/bpf/lpm_trie.c:324 stack backtrace: CPU: 0 PID: 21938 Comm: syz-executor.3 Not tainted 6.9.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 __wake_up_common_lock+0x25/0x1e0 kernel/sched/wait.c:105 rmqueue mm/page_alloc.c:2919 [inline] get_page_from_freelist+0x30f1/0x35b0 mm/page_alloc.c:3314 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] __kmalloc_large_node+0x91/0x1f0 mm/slub.c:3911 __do_kmalloc_node mm/slub.c:3954 [inline] __kmalloc_node+0x33e/0x4e0 mm/slub.c:3973 kmalloc_node include/linux/slab.h:648 [inline] bpf_map_kmalloc_node+0xd3/0x1c0 kernel/bpf/syscall.c:422 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:291 [inline] trie_update_elem+0x1d3/0xc10 kernel/bpf/lpm_trie.c:333 bpf_map_update_value+0x4d3/0x540 kernel/bpf/syscall.c:203 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5648 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3f3bc7dea9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3f3cad30c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f3f3bdabf80 RCX: 00007f3f3bc7dea9 RDX: 0000000000000020 RSI: 0000000020000080 RDI: 0000000000000002 RBP: 00007f3f3bcca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f3f3bdabf80 R15: 00007fff194b95a8