Hello, syzbot found the following issue on: HEAD commit: e4fb79c7 Add linux-next specific files for 20201008 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=12555227900000 kernel config: https://syzkaller.appspot.com/x/.config?x=568d41fe4341ed0f dashboard link: https://syzkaller.appspot.com/bug?extid=cdcbdc0bd42e559b52b9 compiler: gcc (GCC) 10.1.0-syz 20200507 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+cdcbdc0bd42e559b52b9@xxxxxxxxxxxxxxxxxxxxxxxxx ================================ WARNING: inconsistent lock state 5.9.0-rc8-next-20201008-syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz-executor.2/6913 [HC0[0]:SC1[1]:HE0:SE0] takes: ffff888023003c18 (&xa->xa_lock#9){+.?.}-{2:2}, at: xa_destroy+0xaa/0x350 lib/xarray.c:2205 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5419 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] io_uring_add_task_file fs/io_uring.c:8607 [inline] io_uring_add_task_file+0x207/0x430 fs/io_uring.c:8590 io_uring_get_fd fs/io_uring.c:9116 [inline] io_uring_create fs/io_uring.c:9280 [inline] io_uring_setup+0x2727/0x3660 fs/io_uring.c:9314 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 irq event stamp: 362445 hardirqs last enabled at (362444): [<ffffffff8847f0df>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] hardirqs last enabled at (362444): [<ffffffff8847f0df>] _raw_spin_unlock_irqrestore+0x6f/0x90 kernel/locking/spinlock.c:191 hardirqs last disabled at (362445): [<ffffffff8847f6c9>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (362445): [<ffffffff8847f6c9>] _raw_spin_lock_irqsave+0xa9/0xd0 kernel/locking/spinlock.c:159 softirqs last enabled at (361998): [<ffffffff86db0172>] tcp_close+0x8d2/0x1220 net/ipv4/tcp.c:2576 softirqs last disabled at (362079): [<ffffffff88600f2f>] asm_call_irq_on_stack+0xf/0x20 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&xa->xa_lock#9); <Interrupt> lock(&xa->xa_lock#9); *** DEADLOCK *** 1 lock held by syz-executor.2/6913: #0: ffffffff8a554c80 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2474 [inline] #0: ffffffff8a554c80 (rcu_callback){....}-{0:0}, at: rcu_core+0x5d8/0x1240 kernel/rcu/tree.c:2718 stack backtrace: CPU: 0 PID: 6913 Comm: syz-executor.2 Not tainted 5.9.0-rc8-next-20201008-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fb lib/dump_stack.c:118 print_usage_bug kernel/locking/lockdep.c:3715 [inline] valid_state kernel/locking/lockdep.c:3726 [inline] mark_lock_irq kernel/locking/lockdep.c:3929 [inline] mark_lock.cold+0x32/0x74 kernel/locking/lockdep.c:4396 mark_usage kernel/locking/lockdep.c:4281 [inline] __lock_acquire+0x118a/0x56d0 kernel/locking/lockdep.c:4771 lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5419 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x94/0xd0 kernel/locking/spinlock.c:159 xa_destroy+0xaa/0x350 lib/xarray.c:2205 __io_uring_free+0x60/0xc0 fs/io_uring.c:7693 io_uring_free include/linux/io_uring.h:40 [inline] __put_task_struct+0xff/0x3f0 kernel/fork.c:732 put_task_struct include/linux/sched/task.h:111 [inline] delayed_put_task_struct+0x1f6/0x340 kernel/exit.c:172 rcu_do_batch kernel/rcu/tree.c:2484 [inline] rcu_core+0x645/0x1240 kernel/rcu/tree.c:2718 __do_softirq+0x203/0xab6 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 </IRQ> __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9b/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x235/0x280 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:66 Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 RSP: 0018:ffffc900053c7b78 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000002040 RDX: 0000000000008000 RSI: 0000000000000000 RDI: ffffc900161a5fc0 RBP: ffffc900053c7d08 R08: 0000000000000001 R09: ffffc900161a0000 R10: fffff52002c34fff R11: 0000000000000000 R12: ffff88805b9f0380 R13: ffff888010ccae08 R14: 0000000001200000 R15: 0000000000000000 memset include/linux/string.h:384 [inline] alloc_thread_stack_node kernel/fork.c:232 [inline] dup_task_struct kernel/fork.c:864 [inline] copy_process+0x68a/0x6e90 kernel/fork.c:1938 kernel_clone+0xe5/0xae0 kernel/fork.c:2456 __do_sys_clone+0xc8/0x110 kernel/fork.c:2573 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c3fa Code: f7 d8 64 89 04 25 d4 02 00 00 64 4c 8b 0c 25 10 00 00 00 31 d2 4d 8d 91 d0 02 00 00 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 f5 00 00 00 85 c0 41 89 c5 0f 85 fc 00 00 RSP: 002b:00007ffe5dc445b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ffe5dc445b0 RCX: 000000000045c3fa RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007ffe5dc445f0 R08: 0000000000000001 R09: 0000000002f46940 R10: 0000000002f46c10 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffe5dc44640 --- This report is generated by a bot. 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