syzbot

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BUG: KMSAN: uninit-value in bch2_btree_node_get+0x5ed/0x1970 fs/bcachefs/btree_cache.c:1181
 bch2_btree_node_get+0x5ed/0x1970 fs/bcachefs/btree_cache.c:1181
 btree_path_down fs/bcachefs/btree_iter.c:976 [inline]
 bch2_btree_path_traverse_one+0x283d/0x4790 fs/bcachefs/btree_iter.c:1202
 bch2_btree_path_traverse fs/bcachefs/btree_iter.h:249 [inline]
 bch2_btree_iter_peek_node+0x31e/0x10f0 fs/bcachefs/btree_iter.c:1934
 async_btree_node_rewrite_trans fs/bcachefs/btree_update_interior.c:2210 [inline]
 async_btree_node_rewrite_work+0x29b/0x1aa0 fs/bcachefs/btree_update_interior.c:2253
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xc1a/0x1e80 kernel/workqueue.c:3319
 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3400
 kthread+0x6b9/0xef0 kernel/kthread.c:464
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 memcpy_u64s_small fs/bcachefs/util.h:416 [inline]
 bkey_reassemble fs/bcachefs/bkey.h:506 [inline]
 bch2_bkey_buf_reassemble fs/bcachefs/bkey_buf.h:28 [inline]
 btree_node_iter_and_journal_peek+0x889/0x2560 fs/bcachefs/btree_iter.c:918
 btree_path_down fs/bcachefs/btree_iter.c:947 [inline]
 bch2_btree_path_traverse_one+0x2131/0x4790 fs/bcachefs/btree_iter.c:1202
 bch2_btree_path_traverse fs/bcachefs/btree_iter.h:249 [inline]
 bch2_btree_iter_peek_node+0x31e/0x10f0 fs/bcachefs/btree_iter.c:1934
 async_btree_node_rewrite_trans fs/bcachefs/btree_update_interior.c:2210 [inline]
 async_btree_node_rewrite_work+0x29b/0x1aa0 fs/bcachefs/btree_update_interior.c:2253
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xc1a/0x1e80 kernel/workqueue.c:3319
 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3400
 kthread+0x6b9/0xef0 kernel/kthread.c:464
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
 ___kmalloc_large_node+0x22c/0x370 mm/slub.c:4249
 __kmalloc_large_node_noprof+0x3f/0x1e0 mm/slub.c:4266
 __do_kmalloc_node mm/slub.c:4282 [inline]
 __kmalloc_node_noprof+0xc96/0x1250 mm/slub.c:4300
 __kvmalloc_node_noprof+0xc0/0x2d0 mm/util.c:665
 btree_node_data_alloc fs/bcachefs/btree_cache.c:156 [inline]
 bch2_btree_node_mem_alloc+0xa96/0x2f10 fs/bcachefs/btree_cache.c:835
 __bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:304 [inline]
 bch2_btree_reserve_get+0x37f/0x2290 fs/bcachefs/btree_update_interior.c:532
 bch2_btree_update_start+0x1af9/0x2d60 fs/bcachefs/btree_update_interior.c:1232
 bch2_btree_split_leaf+0x120/0xc90 fs/bcachefs/btree_update_interior.c:1853
 bch2_trans_commit_error+0x1c0/0x1d60 fs/bcachefs/btree_trans_commit.c:908
 __bch2_trans_commit+0x1d5f/0xd310 fs/bcachefs/btree_trans_commit.c:1089
 bch2_trans_commit fs/bcachefs/btree_update.h:191 [inline]
 bch2_journal_replay+0x3125/0x4e20 fs/bcachefs/recovery.c:373
 bch2_run_recovery_pass fs/bcachefs/recovery_passes.c:226 [inline]
 bch2_run_recovery_passes+0x5a2/0x1160 fs/bcachefs/recovery_passes.c:291
 bch2_fs_recovery+0x489c/0x6230 fs/bcachefs/recovery.c:936
 bch2_fs_start+0x7ca/0xc20 fs/bcachefs/super.c:1041
 bch2_fs_get_tree+0x1564/0x24e0 fs/bcachefs/fs.c:2203
 vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
 do_new_mount+0x71f/0x15e0 fs/namespace.c:3560
 path_mount+0x742/0x1f10 fs/namespace.c:3887
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount+0x71f/0x800 fs/namespace.c:4088
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4088
 x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 9533 Comm: kworker/u8:1 Tainted: G        W          6.14.0-rc7-syzkaller #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: btree_node_rewrite async_btree_node_rewrite_work
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