======================================================
WARNING: possible circular locking dependency detected
5.2.0-rc7+ #40 Not tainted
------------------------------------------------------
syz-executor292/8718 is trying to acquire lock:
00000000df43932d (&rp->fetch_lock){+.+.}, at: mon_bin_vma_fault+0x73/0x2d0 drivers/usb/mon/mon_bin.c:1237

but task is already holding lock:
00000000a168186b (&mm->mmap_sem#2){++++}, at: __mm_populate+0x270/0x380 mm/gup.c:1588

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&mm->mmap_sem#2){++++}:
       __might_fault mm/memory.c:4496 [inline]
       __might_fault+0x15e/0x1e0 mm/memory.c:4481
       _copy_to_user+0x30/0x120 lib/usercopy.c:25
       copy_to_user include/linux/uaccess.h:152 [inline]
       mon_bin_read+0x329/0x640 drivers/usb/mon/mon_bin.c:825
       do_loop_readv_writev fs/read_write.c:714 [inline]
       do_loop_readv_writev fs/read_write.c:701 [inline]
       do_iter_read+0x4a4/0x660 fs/read_write.c:935
       compat_readv+0x18e/0x200 fs/read_write.c:1186
       do_compat_preadv64+0x190/0x1c0 fs/read_write.c:1235
       __do_compat_sys_preadv fs/read_write.c:1255 [inline]
       __se_compat_sys_preadv fs/read_write.c:1249 [inline]
       __ia32_compat_sys_preadv+0xc7/0x140 fs/read_write.c:1249
       do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
       do_fast_syscall_32+0x27b/0xd7d arch/x86/entry/common.c:408
       entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

-> #0 (&rp->fetch_lock){+.+.}:
       lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
       __mutex_lock_common kernel/locking/mutex.c:926 [inline]
       __mutex_lock+0xf7/0x1310 kernel/locking/mutex.c:1073
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088
       mon_bin_vma_fault+0x73/0x2d0 drivers/usb/mon/mon_bin.c:1237
       __do_fault+0x111/0x4d0 mm/memory.c:3127
       do_cow_fault mm/memory.c:3566 [inline]
       do_fault mm/memory.c:3668 [inline]
       handle_pte_fault mm/memory.c:3897 [inline]
       __handle_mm_fault+0xf67/0x3eb0 mm/memory.c:4021
       handle_mm_fault+0x3b7/0xa90 mm/memory.c:4058
       faultin_page mm/gup.c:654 [inline]
       __get_user_pages+0x7b6/0x1a40 mm/gup.c:857
       populate_vma_page_range+0x20d/0x2a0 mm/gup.c:1560
       __mm_populate+0x204/0x380 mm/gup.c:1608
       mm_populate include/linux/mm.h:2411 [inline]
       vm_mmap_pgoff+0x213/0x230 mm/util.c:368
       ksys_mmap_pgoff+0x4aa/0x630 mm/mmap.c:1611
       __do_sys_mmap_pgoff mm/mmap.c:1622 [inline]
       __se_sys_mmap_pgoff mm/mmap.c:1618 [inline]
       __ia32_sys_mmap_pgoff+0xdd/0x1a0 mm/mmap.c:1618
       do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
       do_fast_syscall_32+0x27b/0xd7d arch/x86/entry/common.c:408
       entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_sem#2);
                               lock(&rp->fetch_lock);
                               lock(&mm->mmap_sem#2);
  lock(&rp->fetch_lock);

 *** DEADLOCK ***

1 lock held by syz-executor292/8718:
 #0: 00000000a168186b (&mm->mmap_sem#2){++++}, at: __mm_populate+0x270/0x380 mm/gup.c:1588

stack backtrace:
CPU: 0 PID: 8718 Comm: syz-executor292 Not tainted 5.2.0-rc7+ #40
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_circular_bug.cold+0x1cc/0x28f kernel/locking/lockdep.c:1565
 check_prev_add kernel/locking/lockdep.c:2310 [inline]
 check_prevs_add kernel/locking/lockdep.c:2418 [inline]
 validate_chain kernel/locking/lockdep.c:2800 [inline]
 __lock_acquire+0x3755/0x5490 kernel/locking/lockdep.c:3793
 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
 __mutex_lock_common kernel/locking/mutex.c:926 [inline]
 __mutex_lock+0xf7/0x1310 kernel/locking/mutex.c:1073
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088
 mon_bin_vma_fault+0x73/0x2d0 drivers/usb/mon/mon_bin.c:1237
 __do_fault+0x111/0x4d0 mm/memory.c:3127
 do_cow_fault mm/memory.c:3566 [inline]
 do_fault mm/memory.c:3668 [inline]
 handle_pte_fault mm/memory.c:3897 [inline]
 __handle_mm_fault+0xf67/0x3eb0 mm/memory.c:4021
 handle_mm_fault+0x3b7/0xa90 mm/memory.c:4058
 faultin_page mm/gup.c:654 [inline]
 __get_user_pages+0x7b6/0x1a40 mm/gup.c:857
 populate_vma_page_range+0x20d/0x2a0 mm/gup.c:1560
 __mm_populate+0x204/0x380 mm/gup.c:1608
 mm_populate include/linux/mm.h:2411 [inline]
 vm_mmap_pgoff+0x213/0x230 mm/util.c:368
 ksys_mmap_pgoff+0x4aa/0x630 mm/mmap.c:1611
 __do_sys_mmap_pgoff mm/mmap.c:1622 [inline]
 __se_sys_mmap_pgoff mm/mmap.c:1618 [inline]
 __ia32_sys_mmap_pgoff+0xdd/0x1a0 mm/mmap.c:1618
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x27b/0xd7d arch/x86/entry/common.c:408
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7fc5849
Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f7fa011c EFLAGS: 00000296 ORIG_RAX: 00000000000000c0
RAX: ffffffffffffffda RBX: 0000000020a05000 RCX: 0000000000400000
RDX: 0000000000000002 RSI: 0000000000008012 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000