loop0: detected capacity change from 0 to 32768
bcachefs (loop0): starting version 1.7: mi_btree_bitmap opts=metadata_checksum=none,data_checksum=none,compression=lz4,erasure_code,degraded,no_splitbrain_check,fsck,norecovery,nojournal_transaction_names,reconstruct_alloc,nocow
bcachefs (loop0): recovering from clean shutdown, journal seq 10
bcachefs (loop0): Version upgrade required:
Version upgrade from 0.24: unwritten_extents to 1.7: mi_btree_bitmap incomplete
Doing incompatible version upgrade from 0.24: unwritten_extents to 1.13: inode_has_child_snapshots
running recovery passes: check_allocations,check_alloc_info,check_lrus,check_btree_backpointers,check_backpointers_to_extents,check_extents_to_backpointers,check_alloc_to_lru_refs,bucket_gens_init,check_snapshot_trees,check_snapshots,check_subvols,check_subvol_children,delete_dead_snapshots,check_inodes,check_extents,check_indirect_extents,check_dirents,check_xattrs,check_root,check_unreachable_inodes,check_subvolume_structure,check_directory_structure,check_nlinks,set_fs_needs_rebalance
bcachefs (loop0): dropping and reconstructing all alloc info
bcachefs (loop0): check_topology... done
bcachefs (loop0): accounting_read... done
bcachefs (loop0): alloc_read... done
bcachefs (loop0): stripes_read... done
bcachefs (loop0): snapshots_read... done
bcachefs (loop0): check_allocations... done
bcachefs (loop0): going read-write
bcachefs (loop0): done starting filesystem
netlink: 4 bytes leftover after parsing attributes in process `syz.0.0'.
======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc6-syzkaller-00169-g906bd684e4b1 #0 Not tainted
------------------------------------------------------
syz.0.0/5328 is trying to acquire lock:
ffffffff8ea17308 (pcpu_alloc_mutex){+.+.}-{3:3}, at: pcpu_alloc_noprof+0x27f/0x16b0 mm/percpu.c:1795
but task is already holding lock:
ffff88804ff01c50 (&bc->lock){+.+.}-{3:3}, at: bch2_btree_node_mem_alloc+0x4ec/0x1340 fs/bcachefs/btree_cache.c:782
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&bc->lock){+.+.}-{3:3}:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
bch2_btree_cache_scan+0x192/0xd00 fs/bcachefs/btree_cache.c:460
do_shrink_slab+0x701/0x1160 mm/shrinker.c:437
shrink_slab+0x1093/0x14d0 mm/shrinker.c:664
shrink_one+0x43b/0x850 mm/vmscan.c:4824
shrink_many mm/vmscan.c:4885 [inline]
lru_gen_shrink_node mm/vmscan.c:4963 [inline]
shrink_node+0x3791/0x3e20 mm/vmscan.c:5943
kswapd_shrink_node mm/vmscan.c:6771 [inline]
balance_pgdat mm/vmscan.c:6963 [inline]
kswapd+0x1ca3/0x3700 mm/vmscan.c:7232
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #1 (fs_reclaim){+.+.}-{0:0}:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
__fs_reclaim_acquire mm/page_alloc.c:3834 [inline]
fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3848
might_alloc include/linux/sched/mm.h:318 [inline]
slab_pre_alloc_hook mm/slub.c:4036 [inline]
slab_alloc_node mm/slub.c:4114 [inline]
__do_kmalloc_node mm/slub.c:4263 [inline]
__kmalloc_noprof+0xa9/0x400 mm/slub.c:4276
kmalloc_noprof include/linux/slab.h:882 [inline]
kzalloc_noprof include/linux/slab.h:1014 [inline]
pcpu_mem_zalloc mm/percpu.c:510 [inline]
pcpu_alloc_chunk mm/percpu.c:1443 [inline]
pcpu_create_chunk+0x57/0xbc0 mm/percpu-vm.c:338
pcpu_balance_populated mm/percpu.c:2075 [inline]
pcpu_balance_workfn+0xc4d/0xd40 mm/percpu.c:2212
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 (pcpu_alloc_mutex){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
pcpu_alloc_noprof+0x27f/0x16b0 mm/percpu.c:1795
__six_lock_init+0x104/0x150 fs/bcachefs/six.c:869
bch2_btree_lock_init+0x38/0x100 fs/bcachefs/btree_locking.c:12
bch2_btree_node_mem_alloc+0x4f8/0x1340 fs/bcachefs/btree_cache.c:785
__bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:325 [inline]
bch2_btree_reserve_get+0x2df/0x1890 fs/bcachefs/btree_update_interior.c:554
bch2_btree_update_start+0xe56/0x14e0 fs/bcachefs/btree_update_interior.c:1252
bch2_btree_split_leaf+0x123/0x840 fs/bcachefs/btree_update_interior.c:1850
bch2_trans_commit_error+0x212/0x1390 fs/bcachefs/btree_trans_commit.c:942
__bch2_trans_commit+0x7ead/0x93c0 fs/bcachefs/btree_trans_commit.c:1140
bch2_trans_commit fs/bcachefs/btree_update.h:184 [inline]
bch2_logged_op_start+0x1c8/0x310 fs/bcachefs/logged_ops.c:92
bch2_truncate+0x19e/0x2d0 fs/bcachefs/io_misc.c:294
bchfs_truncate+0x85f/0xc90 fs/bcachefs/fs-io.c:464
notify_change+0xbca/0xe90 fs/attr.c:503
do_truncate+0x220/0x310 fs/open.c:65
handle_truncate fs/namei.c:3395 [inline]
do_open fs/namei.c:3778 [inline]
path_openat+0x2e1e/0x3590 fs/namei.c:3933
do_filp_open+0x235/0x490 fs/namei.c:3960
do_sys_openat2+0x13e/0x1d0 fs/open.c:1415
do_sys_open fs/open.c:1430 [inline]
__do_sys_open fs/open.c:1438 [inline]
__se_sys_open fs/open.c:1434 [inline]
__x64_sys_open+0x225/0x270 fs/open.c:1434
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:
Chain exists of:
pcpu_alloc_mutex --> fs_reclaim --> &bc->lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&bc->lock);
lock(fs_reclaim);
lock(&bc->lock);
lock(pcpu_alloc_mutex);
*** DEADLOCK ***
6 locks held by syz.0.0/5328:
#0: ffff88803d116420 (sb_writers#11){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
#1: ffff8880124e88c8 (&sb->s_type->i_mutex_key#19){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline]
#1: ffff8880124e88c8 (&sb->s_type->i_mutex_key#19){+.+.}-{3:3}, at: do_truncate+0x20c/0x310 fs/open.c:63
#2: ffff88804ff00a38 (&c->snapshot_create_lock){.+.+}-{3:3}, at: bch2_truncate+0x166/0x2d0 fs/bcachefs/io_misc.c:292
#3: ffff88804ff04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:151 [inline]
#3: ffff88804ff04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:250 [inline]
#3: ffff88804ff04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7de/0xd20 fs/bcachefs/btree_iter.c:3228
#4: ffff88804ff266d0 (&c->gc_lock){++++}-{3:3}, at: bch2_btree_update_start+0x682/0x14e0 fs/bcachefs/btree_update_interior.c:1202
#5: ffff88804ff01c50 (&bc->lock){+.+.}-{3:3}, at: bch2_btree_node_mem_alloc+0x4ec/0x1340 fs/bcachefs/btree_cache.c:782
stack backtrace:
CPU: 0 UID: 0 PID: 5328 Comm: syz.0.0 Not tainted 6.12.0-rc6-syzkaller-00169-g906bd684e4b1 #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+0x241/0x360 lib/dump_stack.c:120
print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
check_noncircular+0x36a/0x4a0 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+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
pcpu_alloc_noprof+0x27f/0x16b0 mm/percpu.c:1795
__six_lock_init+0x104/0x150 fs/bcachefs/six.c:869
bch2_btree_lock_init+0x38/0x100 fs/bcachefs/btree_locking.c:12
bch2_btree_node_mem_alloc+0x4f8/0x1340 fs/bcachefs/btree_cache.c:785
__bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:325 [inline]
bch2_btree_reserve_get+0x2df/0x1890 fs/bcachefs/btree_update_interior.c:554
bch2_btree_update_start+0xe56/0x14e0 fs/bcachefs/btree_update_interior.c:1252
bch2_btree_split_leaf+0x123/0x840 fs/bcachefs/btree_update_interior.c:1850
bch2_trans_commit_error+0x212/0x1390 fs/bcachefs/btree_trans_commit.c:942
__bch2_trans_commit+0x7ead/0x93c0 fs/bcachefs/btree_trans_commit.c:1140
bch2_trans_commit fs/bcachefs/btree_update.h:184 [inline]
bch2_logged_op_start+0x1c8/0x310 fs/bcachefs/logged_ops.c:92
bch2_truncate+0x19e/0x2d0 fs/bcachefs/io_misc.c:294
bchfs_truncate+0x85f/0xc90 fs/bcachefs/fs-io.c:464
notify_change+0xbca/0xe90 fs/attr.c:503
do_truncate+0x220/0x310 fs/open.c:65
handle_truncate fs/namei.c:3395 [inline]
do_open fs/namei.c:3778 [inline]
path_openat+0x2e1e/0x3590 fs/namei.c:3933
do_filp_open+0x235/0x490 fs/namei.c:3960
do_sys_openat2+0x13e/0x1d0 fs/open.c:1415
do_sys_open fs/open.c:1430 [inline]
__do_sys_open fs/open.c:1438 [inline]
__se_sys_open fs/open.c:1434 [inline]
__x64_sys_open+0x225/0x270 fs/open.c:1434
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: 0033:0x7f369917e719
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:00007f3699ef8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f3699335f80 RCX: 00007f369917e719
RDX: 0000000000000000 RSI: 0000000000046342 RDI: 0000000020000040
RBP: 00007f36991f139e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3699335f80 R15: 00007ffea3924aa8
</TASK>
syz.0.0 (5328) used greatest stack depth: 12728 bytes left