BTRFS error (device loop4): open_ctree failed: -4
assertion failed: percpu_counter_sum_positive(em_counter) == 0, in fs/btrfs/disk-io.c:1266
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kernel BUG at fs/btrfs/disk-io.c:1266!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 UID: 0 PID: 6656 Comm: syz.4.28 Not tainted 6.14.0-rc5-syzkaller-g14d05f12084d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : btrfs_free_fs_info+0x320/0x324 fs/btrfs/disk-io.c:1266
lr : btrfs_free_fs_info+0x320/0x324 fs/btrfs/disk-io.c:1266
sp : ffff80009c307760
x29: ffff80009c307760 x28: 1fffe0001e38e80d x27: dfff800000000000
x26: ffff0000c9af55d8 x25: 00000000fffffffc x24: ffff0000f1c74068
x23: ffff0000c9af4000 x22: dfff800000000000 x21: 0000000000000002
x20: ffff0000c9af5150 x19: ffff0000c9af4000 x18: 0000000000000008
x17: 202c30203d3d2029 x16: ffff8000832b8f3c x15: 0000000000000001
x14: 1ffff00013860e48 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000080000 x10: 00000000000242eb x9 : 4508ad9d39d8ce00
x8 : 4508ad9d39d8ce00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff80009c306f38 x4 : ffff80008fcaf7a0 x3 : ffff80008324af54
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 000000000000005a
Call trace:
 btrfs_free_fs_info+0x320/0x324 fs/btrfs/disk-io.c:1266 (P)
 btrfs_kill_super+0x48/0x58 fs/btrfs/super.c:2101
 deactivate_locked_super+0xc4/0x12c fs/super.c:473
 btrfs_get_tree_super fs/btrfs/super.c:1900 [inline]
 btrfs_get_tree+0xe68/0x12c4 fs/btrfs/super.c:2093
 vfs_get_tree+0x90/0x28c fs/super.c:1814
 fc_mount+0x24/0xac fs/namespace.c:1271
 btrfs_get_tree_subvol fs/btrfs/super.c:2051 [inline]
 btrfs_get_tree+0x4f0/0x12c4 fs/btrfs/super.c:2094
 vfs_get_tree+0x90/0x28c fs/super.c:1814
 do_new_mount+0x278/0x900 fs/namespace.c:3560
 path_mount+0x590/0xe04 fs/namespace.c:3887
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount fs/namespace.c:4088 [inline]
 __arm64_sys_mount+0x4f4/0x5d0 fs/namespace.c:4088
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: f004c322 91340042 52809e43 9772d5ef (d4210000) 
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