Hello, syzbot found the following issue on: HEAD commit: 449dc8c9 Merge tag 'for-v5.9' of git://git.kernel.org/pub/.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11293dc6900000 kernel config: https://syzkaller.appspot.com/x/.config?x=9d25235bf0162fbc dashboard link: https://syzkaller.appspot.com/bug?extid=ef4b654b49ed7ff049bf compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=126b0f1a900000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13e32994900000 The issue was bisected to: commit e62753e4e2926f249d088cc0517be5ed4efec6d6 Author: Bijan Mottahedeh <bijan.mottahedeh@xxxxxxxxxx> Date: Sat May 23 04:31:18 2020 +0000 io_uring: call statx directly bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1195de52900000 final oops: https://syzkaller.appspot.com/x/report.txt?x=1395de52900000 console output: https://syzkaller.appspot.com/x/log.txt?x=1595de52900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ef4b654b49ed7ff049bf@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: e62753e4e292 ("io_uring: call statx directly") ======================================================== WARNING: possible irq lock inversion dependency detected 5.8.0-syzkaller #0 Not tainted -------------------------------------------------------- syz-executor659/6838 just changed the state of lock: ffff8880a8bc44d8 (&ctx->completion_lock){-...}-{2:2}, at: io_timeout_fn+0x6b/0x360 fs/io_uring.c:4999 but this lock took another, HARDIRQ-unsafe lock in the past: (&fs->lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs->lock); local_irq_disable(); lock(&ctx->completion_lock); lock(&fs->lock); <Interrupt> lock(&ctx->completion_lock); *** DEADLOCK *** 1 lock held by syz-executor659/6838: #0: ffff8880a8bc4428 (&ctx->uring_lock){+.+.}-{3:3}, at: __do_sys_io_uring_enter fs/io_uring.c:8035 [inline] #0: ffff8880a8bc4428 (&ctx->uring_lock){+.+.}-{3:3}, at: __se_sys_io_uring_enter+0x19d/0x1300 fs/io_uring.c:7995 the shortest dependencies between 2nd lock and 1st lock: -> (&fs->lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __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] set_fs_pwd+0x3b/0x220 fs/fs_struct.c:39 init_chdir+0xe2/0x10b fs/init.c:54 devtmpfs_setup+0xa5/0xd4 drivers/base/devtmpfs.c:415 devtmpfsd+0x11/0x40 drivers/base/devtmpfs.c:430 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 SOFTIRQ-ON-W at: lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __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] set_fs_pwd+0x3b/0x220 fs/fs_struct.c:39 init_chdir+0xe2/0x10b fs/init.c:54 devtmpfs_setup+0xa5/0xd4 drivers/base/devtmpfs.c:415 devtmpfsd+0x11/0x40 drivers/base/devtmpfs.c:430 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 INITIAL USE at: lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __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] set_fs_pwd+0x3b/0x220 fs/fs_struct.c:39 init_chdir+0xe2/0x10b fs/init.c:54 devtmpfs_setup+0xa5/0xd4 drivers/base/devtmpfs.c:415 devtmpfsd+0x11/0x40 drivers/base/devtmpfs.c:430 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 } ... key at: [<ffffffff8b84e190>] copy_fs_struct.__key+0x0/0x10 ... acquired at: lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __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_req_clean_work fs/io_uring.c:1126 [inline] io_dismantle_req+0x285/0x5d0 fs/io_uring.c:1544 __io_free_req+0x24/0x190 fs/io_uring.c:1562 __io_double_put_req fs/io_uring.c:1909 [inline] __io_fail_links+0x1d7/0x6c0 fs/io_uring.c:1659 io_fail_links fs/io_uring.c:1675 [inline] __io_req_find_next fs/io_uring.c:1698 [inline] io_req_find_next+0x101a/0x1260 fs/io_uring.c:1706 io_steal_work fs/io_uring.c:1897 [inline] io_wq_submit_work+0x446/0x590 fs/io_uring.c:5792 io_worker_handle_work+0xf8f/0x1570 fs/io-wq.c:527 io_wqe_worker+0x2ff/0x810 fs/io-wq.c:569 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 -> (&ctx->completion_lock){-...}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x9e/0xc0 kernel/locking/spinlock.c:159 io_timeout_fn+0x6b/0x360 fs/io_uring.c:4999 __run_hrtimer kernel/time/hrtimer.c:1520 [inline] __hrtimer_run_queues+0x47f/0x930 kernel/time/hrtimer.c:1584 hrtimer_interrupt+0x373/0xd60 kernel/time/hrtimer.c:1646 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1079 [inline] __sysvec_apic_timer_interrupt+0xf0/0x260 arch/x86/kernel/apic/apic.c:1096 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] sysvec_apic_timer_interrupt+0x94/0xf0 arch/x86/kernel/apic/apic.c:1090 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 arch_local_irq_enable arch/x86/include/asm/paravirt.h:780 [inline] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0x57/0x80 kernel/locking/spinlock.c:199 spin_unlock_irq include/linux/spinlock.h:404 [inline] io_timeout fs/io_uring.c:5162 [inline] io_issue_sqe+0x5b64/0xb8c0 fs/io_uring.c:5594 __io_queue_sqe+0x287/0xff0 fs/io_uring.c:5981 io_submit_sqe fs/io_uring.c:6130 [inline] io_submit_sqes+0x14cf/0x25d0 fs/io_uring.c:6327 __do_sys_io_uring_enter fs/io_uring.c:8036 [inline] __se_sys_io_uring_enter+0x1af/0x1300 fs/io_uring.c:7995 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 INITIAL USE at: lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x9e/0xc0 kernel/locking/spinlock.c:159 io_cqring_add_event fs/io_uring.c:1419 [inline] __io_req_complete+0x15e/0x2c0 fs/io_uring.c:1458 io_issue_sqe+0x8678/0xb8c0 fs/io_uring.c:3569 io_wq_submit_work+0x35e/0x590 fs/io_uring.c:5775 io_worker_handle_work+0xf8f/0x1570 fs/io-wq.c:527 io_wqe_worker+0x2ff/0x810 fs/io-wq.c:569 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 } ... key at: [<ffffffff8b84ef58>] io_ring_ctx_alloc.__key.111+0x0/0x10 ... acquired at: mark_lock_irq kernel/locking/lockdep.c:3568 [inline] mark_lock+0x529/0x1b00 kernel/locking/lockdep.c:4006 mark_usage kernel/locking/lockdep.c:3902 [inline] __lock_acquire+0xa5c/0x2ab0 kernel/locking/lockdep.c:4380 lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x9e/0xc0 kernel/locking/spinlock.c:159 io_timeout_fn+0x6b/0x360 fs/io_uring.c:4999 __run_hrtimer kernel/time/hrtimer.c:1520 [inline] __hrtimer_run_queues+0x47f/0x930 kernel/time/hrtimer.c:1584 hrtimer_interrupt+0x373/0xd60 kernel/time/hrtimer.c:1646 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1079 [inline] __sysvec_apic_timer_interrupt+0xf0/0x260 arch/x86/kernel/apic/apic.c:1096 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] sysvec_apic_timer_interrupt+0x94/0xf0 arch/x86/kernel/apic/apic.c:1090 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 arch_local_irq_enable arch/x86/include/asm/paravirt.h:780 [inline] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0x57/0x80 kernel/locking/spinlock.c:199 spin_unlock_irq include/linux/spinlock.h:404 [inline] io_timeout fs/io_uring.c:5162 [inline] io_issue_sqe+0x5b64/0xb8c0 fs/io_uring.c:5594 __io_queue_sqe+0x287/0xff0 fs/io_uring.c:5981 io_submit_sqe fs/io_uring.c:6130 [inline] io_submit_sqes+0x14cf/0x25d0 fs/io_uring.c:6327 __do_sys_io_uring_enter fs/io_uring.c:8036 [inline] __se_sys_io_uring_enter+0x1af/0x1300 fs/io_uring.c:7995 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 stack backtrace: CPU: 1 PID: 6838 Comm: syz-executor659 Not tainted 5.8.0-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+0x1f0/0x31e lib/dump_stack.c:118 print_irq_inversion_bug+0xb67/0xe90 kernel/locking/lockdep.c:3428 check_usage_forwards+0x13f/0x240 kernel/locking/lockdep.c:3453 mark_lock_irq kernel/locking/lockdep.c:3568 [inline] mark_lock+0x529/0x1b00 kernel/locking/lockdep.c:4006 mark_usage kernel/locking/lockdep.c:3902 [inline] __lock_acquire+0xa5c/0x2ab0 kernel/locking/lockdep.c:4380 lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x9e/0xc0 kernel/locking/spinlock.c:159 io_timeout_fn+0x6b/0x360 fs/io_uring.c:4999 __run_hrtimer kernel/time/hrtimer.c:1520 [inline] __hrtimer_run_queues+0x47f/0x930 kernel/time/hrtimer.c:1584 hrtimer_interrupt+0x373/0xd60 kernel/time/hrtimer.c:1646 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1079 [inline] __sysvec_apic_timer_interrupt+0xf0/0x260 arch/x86/kernel/apic/apic.c:1096 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 </IRQ> __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] sysvec_apic_timer_interrupt+0x94/0xf0 arch/x86/kernel/apic/apic.c:1090 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x57/0x80 kernel/locking/spinlock.c:199 Code: 00 00 00 00 fc ff df 80 3c 08 00 74 0c 48 c7 c7 c8 14 4d 89 e8 6a 28 8b f9 48 83 3d 0a a9 23 01 00 74 25 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 6f 62 27 f9 65 8b 05 34 92 d8 77 85 c0 74 02 5b RSP: 0018:ffffc9000102f8f0 EFLAGS: 00000286 RAX: 1ffffffff129a299 RBX: ffff8880a8bc44c0 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff88296b8f RBP: ffffc9000102fb80 R08: dffffc0000000000 R09: fffffbfff167c6b8 R10: fffffbfff167c6b8 R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff8880a2dfdc08 R15: ffff8880a2dfdc58 spin_unlock_irq include/linux/spinlock.h:404 [inline] io_timeout fs/io_uring.c:5162 [inline] io_issue_sqe+0x5b64/0xb8c0 fs/io_uring.c:5594 __io_queue_sqe+0x287/0xff0 fs/io_uring.c:5981 io_submit_sqe fs/io_uring.c:6130 [inline] io_submit_sqes+0x14cf/0x25d0 fs/io_uring.c:6327 __do_sys_io_uring_enter fs/io_uring.c:8036 [inline] __se_sys_io_uring_enter+0x1af/0x1300 fs/io_uring.c:7995 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x440b99 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffea6abdbf8 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440b99 RDX: 0000000000000000 RSI: 000000000000450c RDI: 0000000000000005 RBP: 00000000006cb018 R08 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
