======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.256/7158 is trying to acquire lock:
ffff88802fee4610 (sb_internal){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
ffff88802fee4610 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1916 [inline]
ffff88802fee4610 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs.h:2099 [inline]
ffff88802fee4610 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x2d6/0xee0 fs/ext4/inode.c:215
but task is already holding lock:
ffff88802fee2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_write fs/ext4/ext4.h:1808 [inline]
ffff88802fee2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x2f3/0x1010 fs/ext4/migrate.c:438
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
percpu_down_read_internal+0x48/0x1c0 include/linux/percpu-rwsem.h:53
percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
ext4_writepages_down_read fs/ext4/ext4.h:1796 [inline]
ext4_writepages+0x1cc/0x350 fs/ext4/inode.c:3024
do_writepages+0x32e/0x550 mm/page-writeback.c:2604
__writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1719
writeback_single_inode+0x1f9/0x6a0 fs/fs-writeback.c:1840
write_inode_now+0x160/0x1d0 fs/fs-writeback.c:2903
iput_final fs/inode.c:1901 [inline]
iput+0x830/0xc50 fs/inode.c:1966
ext4_xattr_block_set+0x1fce/0x2ac0 fs/ext4/xattr.c:2199
ext4_xattr_move_to_block fs/ext4/xattr.c:2664 [inline]
ext4_xattr_make_inode_space fs/ext4/xattr.c:2739 [inline]
ext4_expand_extra_isize_ea+0x12da/0x1ea0 fs/ext4/xattr.c:2827
__ext4_expand_extra_isize+0x30d/0x400 fs/ext4/inode.c:6364
ext4_try_to_expand_extra_isize fs/ext4/inode.c:6407 [inline]
__ext4_mark_inode_dirty+0x46c/0x700 fs/ext4/inode.c:6485
ext4_evict_inode+0x80d/0xee0 fs/ext4/inode.c:254
evict+0x504/0x9c0 fs/inode.c:810
ext4_orphan_cleanup+0xc20/0x1460 fs/ext4/orphan.c:470
__ext4_fill_super fs/ext4/super.c:5617 [inline]
ext4_fill_super+0x5920/0x61e0 fs/ext4/super.c:5736
get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
vfs_get_tree+0x92/0x2b0 fs/super.c:1751
fc_mount fs/namespace.c:1208 [inline]
do_new_mount_fc fs/namespace.c:3651 [inline]
do_new_mount+0x302/0xa10 fs/namespace.c:3727
do_mount fs/namespace.c:4050 [inline]
__do_sys_mount fs/namespace.c:4238 [inline]
__se_sys_mount+0x313/0x410 fs/namespace.c:4215
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (sb_internal){.+.+}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
percpu_down_read_internal+0x48/0x1c0 include/linux/percpu-rwsem.h:53
percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
__sb_start_write include/linux/fs.h:1916 [inline]
sb_start_intwrite include/linux/fs.h:2099 [inline]
ext4_evict_inode+0x2d6/0xee0 fs/ext4/inode.c:215
evict+0x504/0x9c0 fs/inode.c:810
ext4_ext_migrate+0xd23/0x1010 fs/ext4/migrate.c:588
__ext4_ioctl fs/ext4/ioctl.c:1694 [inline]
ext4_ioctl+0x204b/0x48e0 fs/ext4/ioctl.c:1923
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sbi->s_writepages_rwsem);
lock(sb_internal);
lock(&sbi->s_writepages_rwsem);
rlock(sb_internal);
*** DEADLOCK ***
3 locks held by syz.0.256/7158:
#0: ffff88802fee4420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write_file+0x60/0x200 fs/namespace.c:552
#1: ffff88807caa9700 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
#1: ffff88807caa9700 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: __ext4_ioctl fs/ext4/ioctl.c:1693 [inline]
#1: ffff88807caa9700 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: ext4_ioctl+0x2043/0x48e0 fs/ext4/ioctl.c:1923
#2: ffff88802fee2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_write fs/ext4/ext4.h:1808 [inline]
#2: ffff88802fee2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x2f3/0x1010 fs/ext4/migrate.c:438
stack backtrace:
CPU: 0 UID: 0 PID: 7158 Comm: syz.0.256 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043
check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2175
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
percpu_down_read_internal+0x48/0x1c0 include/linux/percpu-rwsem.h:53
percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
__sb_start_write include/linux/fs.h:1916 [inline]
sb_start_intwrite include/linux/fs.h:2099 [inline]
ext4_evict_inode+0x2d6/0xee0 fs/ext4/inode.c:215
evict+0x504/0x9c0 fs/inode.c:810
ext4_ext_migrate+0xd23/0x1010 fs/ext4/migrate.c:588
__ext4_ioctl fs/ext4/ioctl.c:1694 [inline]
ext4_ioctl+0x204b/0x48e0 fs/ext4/ioctl.c:1923
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f70e578f6c9
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:00007f70e65e9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f70e59e5fa0 RCX: 00007f70e578f6c9
RDX: 0000000000000000 RSI: 0000000000006609 RDI: 0000000000000004
RBP: 00007f70e5811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f70e59e6038 R14: 00007f70e59e5fa0 R15: 00007ffe88ccf978
</TASK>