loop7: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
6.14.0-rc7-syzkaller-00179-gb3ee1e460951 #0 Not tainted
------------------------------------------------------
syz.7.1860/11291 is trying to acquire lock:
ffff88806b928be0 (&mm->mmap_lock){++++}-{4:4}, at: gup_fast_fallback+0x246/0x29c0 mm/gup.c:3406

but task is already holding lock:
ffff888055a16a68 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
ffff888055a16a68 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: __blockdev_direct_IO+0x31d/0x4890 fs/direct-io.c:1140

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       down_write+0x99/0x220 kernel/locking/rwsem.c:1577
       inode_lock include/linux/fs.h:877 [inline]
       ntfs_file_mmap+0x5bc/0x850 fs/ntfs3/file.c:379
       call_mmap include/linux/fs.h:2245 [inline]
       mmap_file mm/internal.h:124 [inline]
       __mmap_new_file_vma mm/vma.c:2296 [inline]
       __mmap_new_vma mm/vma.c:2360 [inline]
       __mmap_region mm/vma.c:2462 [inline]
       mmap_region+0x246f/0x2fc0 mm/vma.c:2540
       do_mmap+0xecc/0x13a0 mm/mmap.c:561
       vm_mmap_pgoff+0x2a0/0x530 mm/util.c:578
       ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:607
       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

-> #0 (&mm->mmap_lock){++++}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3163 [inline]
       check_prevs_add kernel/locking/lockdep.c:3282 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
       __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       gup_fast_fallback+0x25f/0x29c0 mm/gup.c:3406
       pin_user_pages_fast+0xcc/0x160 mm/gup.c:3530
       iov_iter_extract_user_pages lib/iov_iter.c:1849 [inline]
       iov_iter_extract_pages+0x3bb/0x5c0 lib/iov_iter.c:1912
       dio_refill_pages fs/direct-io.c:172 [inline]
       dio_get_page fs/direct-io.c:213 [inline]
       do_direct_IO fs/direct-io.c:915 [inline]
       __blockdev_direct_IO+0x1443/0x4890 fs/direct-io.c:1243
       blockdev_direct_IO include/linux/fs.h:3412 [inline]
       ntfs_direct_IO+0x194/0x370 fs/ntfs3/inode.c:809
       generic_file_read_iter+0x343/0x550 mm/filemap.c:2870
       aio_read+0x365/0x500 fs/aio.c:1602
       io_submit_one+0x884/0x18a0 fs/aio.c:2052
       __do_sys_io_submit fs/aio.c:2111 [inline]
       __se_sys_io_submit+0x171/0x2e0 fs/aio.c:2081
       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

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sb->s_type->i_mutex_key#23);
                               lock(&mm->mmap_lock);
                               lock(&sb->s_type->i_mutex_key#23);
  rlock(&mm->mmap_lock);

 *** DEADLOCK ***

1 lock held by syz.7.1860/11291:
 #0: ffff888055a16a68 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
 #0: ffff888055a16a68 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: __blockdev_direct_IO+0x31d/0x4890 fs/direct-io.c:1140

stack backtrace:
CPU: 0 UID: 0 PID: 11291 Comm: syz.7.1860 Not tainted 6.14.0-rc7-syzkaller-00179-gb3ee1e460951 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __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:2076
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
 gup_fast_fallback+0x25f/0x29c0 mm/gup.c:3406
 pin_user_pages_fast+0xcc/0x160 mm/gup.c:3530
 iov_iter_extract_user_pages lib/iov_iter.c:1849 [inline]
 iov_iter_extract_pages+0x3bb/0x5c0 lib/iov_iter.c:1912
 dio_refill_pages fs/direct-io.c:172 [inline]
 dio_get_page fs/direct-io.c:213 [inline]
 do_direct_IO fs/direct-io.c:915 [inline]
 __blockdev_direct_IO+0x1443/0x4890 fs/direct-io.c:1243
 blockdev_direct_IO include/linux/fs.h:3412 [inline]
 ntfs_direct_IO+0x194/0x370 fs/ntfs3/inode.c:809
 generic_file_read_iter+0x343/0x550 mm/filemap.c:2870
 aio_read+0x365/0x500 fs/aio.c:1602
 io_submit_one+0x884/0x18a0 fs/aio.c:2052
 __do_sys_io_submit fs/aio.c:2111 [inline]
 __se_sys_io_submit+0x171/0x2e0 fs/aio.c:2081
 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
RIP: 0033:0x7fa7d178d169
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:00007fa7d2592038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1
RAX: ffffffffffffffda RBX: 00007fa7d19a5fa0 RCX: 00007fa7d178d169
RDX: 0000200000000540 RSI: 0000000000003f0a RDI: 00007fa7d2550000
RBP: 00007fa7d180e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa7d19a5fa0 R15: 00007ffc54ce4a28
 </TASK>