====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc7-syzkaller-00191-gfda5e3f28400 #0 Not tainted ------------------------------------------------------ syz.7.1888/14748 is trying to acquire lock: ffff88807eae4fe0 ( &mm->mmap_lock){++++}-{4:4}, at: __might_fault+0xaa/0x120 mm/memory.c:6751 but task is already holding lock: ffff888142b3a670 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0xdd/0x9a0 kernel/trace/blktrace.c:735 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&q->debugfs_mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_mq_init_sched+0x3fa/0x830 block/blk-mq-sched.c:473 elevator_init_mq+0x20e/0x320 block/elevator.c:610 add_disk_fwnode+0x10d/0xf80 block/genhd.c:413 sd_probe+0xba6/0x1100 drivers/scsi/sd.c:4024 really_probe+0x2b8/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:459 __device_attach_async_helper+0x22d/0x300 drivers/base/dd.c:987 async_run_entry_fn+0xa8/0x420 kernel/async.c:129 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #4 (&q->q_usage_counter(queue)#50){++++}-{0:0} : lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 blk_queue_enter+0xe1/0x600 block/blk-core.c:328 blk_mq_alloc_request+0x4fa/0xaa0 block/blk-mq.c:652 scsi_alloc_request drivers/scsi/scsi_lib.c:1225 [inline] scsi_execute_cmd+0x16c/0x10e0 drivers/scsi/scsi_lib.c:307 read_capacity_16+0x2b4/0x1450 drivers/scsi/sd.c:2655 sd_read_capacity drivers/scsi/sd.c:2824 [inline] sd_revalidate_disk+0x1013/0xbce0 drivers/scsi/sd.c:3734 sd_probe+0x9fa/0x1100 drivers/scsi/sd.c:4010 really_probe+0x2b8/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:459 __device_attach_async_helper+0x22d/0x300 drivers/base/dd.c:987 async_run_entry_fn+0xa8/0x420 kernel/async.c:129 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #3 (&q->limits_lock){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 queue_limits_start_update include/linux/blkdev.h:947 [inline] loop_reconfigure_limits+0x43f/0x900 drivers/block/loop.c:998 loop_set_block_size drivers/block/loop.c:1473 [inline] lo_simple_ioctl drivers/block/loop.c:1496 [inline] lo_ioctl+0x1351/0x1f50 drivers/block/loop.c:1559 lo_compat_ioctl+0x292/0x330 drivers/block/loop.c:1692 compat_blkdev_ioctl+0x5d8/0x7b0 block/ioctl.c:749 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x502/0xc10 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #2 (&q->q_usage_counter(io)#23){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 bio_queue_enter block/blk.h:75 [inline] blk_mq_submit_bio+0x1536/0x2390 block/blk-mq.c:3090 __submit_bio+0x2c6/0x560 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 mpage_bio_submit_read fs/mpage.c:75 [inline] mpage_readahead+0x630/0x780 fs/mpage.c:377 read_pages+0x176/0x750 mm/readahead.c:160 page_cache_ra_unbounded+0x606/0x720 mm/readahead.c:295 do_page_cache_ra mm/readahead.c:325 [inline] force_page_cache_ra mm/readahead.c:354 [inline] page_cache_sync_ra+0x3c5/0xad0 mm/readahead.c:566 page_cache_sync_readahead include/linux/pagemap.h:1397 [inline] filemap_get_pages+0x605/0x2080 mm/filemap.c:2537 filemap_read+0x452/0xf50 mm/filemap.c:2637 blkdev_read_iter+0x2d8/0x430 block/fops.c:770 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x991/0xb70 fs/read_write.c:565 ksys_read+0x18f/0x2b0 fs/read_write.c:708 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 -> #1 (mapping.invalidate_lock#2){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1524 filemap_invalidate_lock_shared include/linux/fs.h:873 [inline] page_cache_ra_unbounded+0x142/0x720 mm/readahead.c:226 do_async_mmap_readahead mm/filemap.c:3222 [inline] filemap_fault+0x818/0x1490 mm/filemap.c:3321 __do_fault+0x135/0x390 mm/memory.c:4907 do_read_fault mm/memory.c:5322 [inline] do_fault mm/memory.c:5456 [inline] do_pte_missing mm/memory.c:3979 [inline] handle_pte_fault+0x39eb/0x5ed0 mm/memory.c:5801 __handle_mm_fault mm/memory.c:5944 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6112 faultin_page mm/gup.c:1196 [inline] __get_user_pages+0x1c82/0x49e0 mm/gup.c:1494 __get_user_pages_locked mm/gup.c:1760 [inline] get_user_pages_unlocked+0x2a8/0x9d0 mm/gup.c:2737 hva_to_pfn_slow virt/kvm/kvm_main.c:2820 [inline] hva_to_pfn+0x445/0xfe0 virt/kvm/kvm_main.c:2916 kvm_follow_pfn virt/kvm/kvm_main.c:2963 [inline] __kvm_faultin_pfn+0x497/0x580 virt/kvm/kvm_main.c:2984 __kvm_mmu_faultin_pfn arch/x86/kvm/mmu/mmu.c:4342 [inline] kvm_mmu_faultin_pfn+0x6c3/0x1580 arch/x86/kvm/mmu/mmu.c:4462 kvm_tdp_mmu_page_fault arch/x86/kvm/mmu/mmu.c:4630 [inline] kvm_tdp_page_fault+0x215/0x300 arch/x86/kvm/mmu/mmu.c:4666 kvm_mmu_do_page_fault+0x583/0xca0 arch/x86/kvm/mmu/mmu_internal.h:325 kvm_mmu_page_fault+0x2db/0xc30 arch/x86/kvm/mmu/mmu.c:6078 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6620 [inline] vmx_handle_exit+0x10e4/0x1e90 arch/x86/kvm/vmx/vmx.c:6637 vcpu_enter_guest arch/x86/kvm/x86.c:11081 [inline] vcpu_run+0x586a/0x8a90 arch/x86/kvm/x86.c:11242 kvm_arch_vcpu_ioctl_run+0xa76/0x19d0 arch/x86/kvm/x86.c:11560 kvm_vcpu_ioctl+0x920/0xea0 virt/kvm/kvm_main.c:4340 kvm_vcpu_compat_ioctl+0x23f/0x450 virt/kvm/kvm_main.c:4555 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x502/0xc10 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #0 (&mm->mmap_lock){++++}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __might_fault+0xc6/0x120 mm/memory.c:6751 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x2a/0xc0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] compat_blk_trace_setup kernel/trace/blktrace.c:664 [inline] blk_trace_ioctl+0x295/0x9a0 kernel/trace/blktrace.c:745 compat_blkdev_ioctl+0x462/0x7b0 block/ioctl.c:742 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x502/0xc10 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e other info that might help us debug this: Chain exists of: &mm->mmap_lock --> &q->q_usage_counter(queue)#50 --> &q->debugfs_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->debugfs_mutex); lock(&q->q_usage_counter(queue)#50 ); lock(&q->debugfs_mutex); rlock(&mm->mmap_lock); *** DEADLOCK *** 1 lock held by syz.7.1888/14748: #0: ffff888142b3a670 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0xdd/0x9a0 kernel/trace/blktrace.c:735 stack backtrace: CPU: 0 UID: 0 PID: 14748 Comm: syz.7.1888 Not tainted 6.13.0-rc7-syzkaller-00191-gfda5e3f28400 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __might_fault+0xc6/0x120 mm/memory.c:6751 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x2a/0xc0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] compat_blk_trace_setup kernel/trace/blktrace.c:664 [inline] blk_trace_ioctl+0x295/0x9a0 kernel/trace/blktrace.c:745 compat_blkdev_ioctl+0x462/0x7b0 block/ioctl.c:742 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x502/0xc10 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7f07579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f501455c EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 000000000000000a RCX: 00000000c0401273 RDX: 0000000020000780 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop