======================================================
WARNING: possible circular locking dependency detected
6.13.0-rc3-syzkaller-00193-ge9b8ffafd20a #0 Not tainted
------------------------------------------------------
syz.1.223/6820 is trying to acquire lock:
ffff888025ac74b0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_mq_exit_sched+0xd1/0x310 block/blk-mq-sched.c:531
but task is already holding lock:
ffff888106ba10b8 (&eq->sysfs_lock){+.+.}-{4:4}, at: elevator_exit block/elevator.c:158 [inline]
ffff888106ba10b8 (&eq->sysfs_lock){+.+.}-{4:4}, at: elevator_disable+0xb5/0x490 block/elevator.c:674
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&eq->sysfs_lock){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
elevator_exit block/elevator.c:158 [inline]
elevator_disable+0xb5/0x490 block/elevator.c:674
blk_mq_elv_switch_none block/blk-mq.c:4942 [inline]
__blk_mq_update_nr_hw_queues+0x41e/0x1590 block/blk-mq.c:5005
blk_mq_update_nr_hw_queues+0x2a/0x40 block/blk-mq.c:5068
nbd_start_device+0x15b/0xd70 drivers/block/nbd.c:1413
nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline]
__nbd_ioctl drivers/block/nbd.c:1539 [inline]
nbd_ioctl+0x21a/0xfd0 drivers/block/nbd.c:1579
blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #3 (&q->q_usage_counter(io)#51){++++}-{0:0}:
bio_queue_enter block/blk.h:75 [inline]
blk_mq_submit_bio+0x1fb6/0x24c0 block/blk-mq.c:3090
__submit_bio+0x384/0x540 block/blk-core.c:629
__submit_bio_noacct_mq block/blk-core.c:710 [inline]
submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:739
submit_bio_noacct+0x93a/0x1e20 block/blk-core.c:868
mpage_bio_submit_read fs/mpage.c:75 [inline]
mpage_readahead+0x41d/0x590 fs/mpage.c:377
read_pages+0x1a8/0xdc0 mm/readahead.c:160
page_cache_ra_unbounded+0x3dc/0x750 mm/readahead.c:295
do_page_cache_ra mm/readahead.c:325 [inline]
force_page_cache_ra+0x24b/0x340 mm/readahead.c:354
page_cache_sync_ra+0x110/0x9c0 mm/readahead.c:566
page_cache_sync_readahead include/linux/pagemap.h:1397 [inline]
filemap_get_pages+0xd7b/0x1be0 mm/filemap.c:2546
filemap_read+0x3ca/0xd70 mm/filemap.c:2646
blkdev_read_iter+0x187/0x480 block/fops.c:770
new_sync_read fs/read_write.c:484 [inline]
vfs_read+0x87f/0xbe0 fs/read_write.c:565
ksys_read+0x12b/0x250 fs/read_write.c:708
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #2 (mapping.invalidate_lock#2){.+.+}-{4:4}:
down_read+0x9a/0x330 kernel/locking/rwsem.c:1524
filemap_invalidate_lock_shared include/linux/fs.h:873 [inline]
page_cache_ra_unbounded+0x173/0x750 mm/readahead.c:226
do_page_cache_ra mm/readahead.c:325 [inline]
page_cache_ra_order+0x8f2/0xc80 mm/readahead.c:524
do_sync_mmap_readahead mm/filemap.c:3203 [inline]
filemap_fault+0x14a5/0x2820 mm/filemap.c:3344
__do_fault+0x10a/0x490 mm/memory.c:4907
do_read_fault mm/memory.c:5322 [inline]
do_fault mm/memory.c:5456 [inline]
do_pte_missing+0xebd/0x3e00 mm/memory.c:3979
handle_pte_fault mm/memory.c:5801 [inline]
__handle_mm_fault+0x103c/0x2a40 mm/memory.c:5944
handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6112
faultin_page mm/gup.c:1196 [inline]
__get_user_pages+0x8d9/0x3b50 mm/gup.c:1494
__get_user_pages_locked mm/gup.c:1760 [inline]
get_user_pages_unlocked+0x1c2/0x780 mm/gup.c:2737
hva_to_pfn_slow virt/kvm/kvm_main.c:2820 [inline]
hva_to_pfn+0x8be/0xc20 virt/kvm/kvm_main.c:2916
kvm_follow_pfn virt/kvm/kvm_main.c:2963 [inline]
kvm_follow_pfn+0x29f/0x3f0 virt/kvm/kvm_main.c:2947
__kvm_faultin_pfn+0x11c/0x1a0 virt/kvm/kvm_main.c:2984
__kvm_mmu_faultin_pfn arch/x86/kvm/mmu/mmu.c:4354 [inline]
kvm_mmu_faultin_pfn+0x469/0x1f30 arch/x86/kvm/mmu/mmu.c:4474
kvm_tdp_mmu_page_fault arch/x86/kvm/mmu/mmu.c:4642 [inline]
kvm_tdp_page_fault+0x182/0x3d0 arch/x86/kvm/mmu/mmu.c:4678
kvm_mmu_do_page_fault+0x58d/0x690 arch/x86/kvm/mmu/mmu_internal.h:325
kvm_mmu_page_fault+0x20f/0x1bb0 arch/x86/kvm/mmu/mmu.c:6090
handle_ept_violation+0x25a/0x640 arch/x86/kvm/vmx/vmx.c:5832
__vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6620 [inline]
vmx_handle_exit+0x733/0x1f70 arch/x86/kvm/vmx/vmx.c:6637
vcpu_enter_guest arch/x86/kvm/x86.c:11081 [inline]
vcpu_run+0x3047/0x4f50 arch/x86/kvm/x86.c:11242
kvm_arch_vcpu_ioctl_run+0x44a/0x1740 arch/x86/kvm/x86.c:11560
kvm_vcpu_ioctl+0x6ce/0x1520 virt/kvm/kvm_main.c:4340
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #1 (&mm->mmap_lock){++++}-{4:4}:
__might_fault mm/memory.c:6751 [inline]
__might_fault+0x11b/0x190 mm/memory.c:6744
_inline_copy_from_user include/linux/uaccess.h:162 [inline]
_copy_from_user+0x29/0xd0 lib/usercopy.c:18
copy_from_user include/linux/uaccess.h:212 [inline]
__blk_trace_setup+0xa8/0x180 kernel/trace/blktrace.c:626
blk_trace_ioctl+0x163/0x290 kernel/trace/blktrace.c:740
blkdev_ioctl+0x109/0x6d0 block/ioctl.c:682
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&q->debugfs_mutex){+.+.}-{4:4}:
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain kernel/locking/lockdep.c:3904 [inline]
__lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
blk_mq_exit_sched+0xd1/0x310 block/blk-mq-sched.c:531
elevator_exit block/elevator.c:159 [inline]
elevator_disable+0xc0/0x490 block/elevator.c:674
blk_mq_elv_switch_none block/blk-mq.c:4942 [inline]
__blk_mq_update_nr_hw_queues+0x41e/0x1590 block/blk-mq.c:5005
blk_mq_update_nr_hw_queues+0x2a/0x40 block/blk-mq.c:5068
nbd_start_device+0x15b/0xd70 drivers/block/nbd.c:1413
nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline]
__nbd_ioctl drivers/block/nbd.c:1539 [inline]
nbd_ioctl+0x21a/0xfd0 drivers/block/nbd.c:1579
blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Chain exists of:
&q->debugfs_mutex --> &q->q_usage_counter(io)#51 --> &eq->sysfs_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&eq->sysfs_lock);
lock(&q->q_usage_counter(io)#51);
lock(&eq->sysfs_lock);
lock(&q->debugfs_mutex);
*** DEADLOCK ***
7 locks held by syz.1.223/6820:
#0: ffff8880264fa198 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x151/0xfd0 drivers/block/nbd.c:1572
#1: ffff8880264fa0d8 (&set->tag_list_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x20/0x40 block/blk-mq.c:5067
#2: ffff888025ac7200 (&q->sysfs_dir_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues+0x205/0x1590 block/blk-mq.c:4995
#3: ffff888025ac7170 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues+0x214/0x1590 block/blk-mq.c:4996
#4: ffff888025ac6c40 (&q->q_usage_counter(io)#50){+.+.}-{0:0}, at: blk_mq_freeze_queue block/blk-mq.c:213 [inline]
#4: ffff888025ac6c40 (&q->q_usage_counter(io)#50){+.+.}-{0:0}, at: __blk_mq_update_nr_hw_queues+0x21c/0x1590 block/blk-mq.c:4997
#5: ffff888025ac6c78 (&q->q_usage_counter(queue)#34){+.+.}-{0:0}, at: blk_mq_freeze_queue block/blk-mq.c:213 [inline]
#5: ffff888025ac6c78 (&q->q_usage_counter(queue)#34){+.+.}-{0:0}, at: __blk_mq_update_nr_hw_queues+0x21c/0x1590 block/blk-mq.c:4997
#6: ffff888106ba10b8 (&eq->sysfs_lock){+.+.}-{4:4}, at: elevator_exit block/elevator.c:158 [inline]
#6: ffff888106ba10b8 (&eq->sysfs_lock){+.+.}-{4:4}, at: elevator_disable+0xb5/0x490 block/elevator.c:674
stack backtrace:
CPU: 2 UID: 0 PID: 6820 Comm: syz.1.223 Not tainted 6.13.0-rc3-syzkaller-00193-ge9b8ffafd20a #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
check_noncircular+0x31a/0x400 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 kernel/locking/lockdep.c:3904 [inline]
__lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
blk_mq_exit_sched+0xd1/0x310 block/blk-mq-sched.c:531
elevator_exit block/elevator.c:159 [inline]
elevator_disable+0xc0/0x490 block/elevator.c:674
blk_mq_elv_switch_none block/blk-mq.c:4942 [inline]
__blk_mq_update_nr_hw_queues+0x41e/0x1590 block/blk-mq.c:5005
blk_mq_update_nr_hw_queues+0x2a/0x40 block/blk-mq.c:5068
nbd_start_device+0x15b/0xd70 drivers/block/nbd.c:1413
nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline]
__nbd_ioctl drivers/block/nbd.c:1539 [inline]
nbd_ioctl+0x21a/0xfd0 drivers/block/nbd.c:1579
blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f112d785d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f112e547038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f112d976080 RCX: 00007f112d785d29
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f112d801aa8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f112d976080 R15: 00007ffdcb2f60f8
</TASK>