=====================================================
BUG: KMSAN: uninit-value in btrfs_clean_tree_block+0x2c3/0x370 fs/btrfs/disk-io.c:1126
 btrfs_clean_tree_block+0x2c3/0x370 fs/btrfs/disk-io.c:1126
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4741 [inline]
 btrfs_alloc_tree_block+0x745/0x20c0 fs/btrfs/extent-tree.c:4818
 __btrfs_cow_block+0x823/0x2490 fs/btrfs/ctree.c:415
 btrfs_cow_block+0xa4a/0xc80 fs/btrfs/ctree.c:570
 commit_cowonly_roots+0x1c5/0x14c0 fs/btrfs/transaction.c:1241
 btrfs_commit_transaction+0x1d8a/0x4b10 fs/btrfs/transaction.c:2288
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4303
 close_ctree+0x4e4/0xfbd fs/btrfs/disk-io.c:4370
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:340
 generic_shutdown_super+0x2bb/0x660 fs/super.c:465
 kill_anon_super+0x63/0xb0 fs/super.c:1057
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2348
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x19e/0x1a0 fs/super.c:366
 cleanup_mnt+0x797/0x870 fs/namespace.c:1137
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1144
 task_work_run+0x1f0/0x2c0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x3fc/0x490 kernel/entry/common.c:176
 exit_to_user_mode_prepare kernel/entry/common.c:208 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x80/0xc0 kernel/entry/common.c:302
 __do_fast_syscall_32+0xa5/0xf0 arch/x86/entry/common.c:183
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 __alloc_pages+0x8b3/0xfb0 mm/page_alloc.c:5423
 alloc_pages+0xa39/0xde0 mm/mempolicy.c:2191
 __page_cache_alloc mm/filemap.c:1022 [inline]
 pagecache_get_page+0x1384/0x1ec0 mm/filemap.c:1940
 find_or_create_page include/linux/pagemap.h:420 [inline]
 alloc_extent_buffer+0x8c5/0x3420 fs/btrfs/extent_io.c:6124
 btrfs_find_create_tree_block+0xb2/0xd0 fs/btrfs/disk-io.c:1090
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4717 [inline]
 btrfs_alloc_tree_block+0x507/0x20c0 fs/btrfs/extent-tree.c:4818
 __btrfs_cow_block+0x823/0x2490 fs/btrfs/ctree.c:415
 btrfs_cow_block+0xa4a/0xc80 fs/btrfs/ctree.c:570
 commit_cowonly_roots+0x1c5/0x14c0 fs/btrfs/transaction.c:1241
 btrfs_commit_transaction+0x1d8a/0x4b10 fs/btrfs/transaction.c:2288
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4303
 close_ctree+0x4e4/0xfbd fs/btrfs/disk-io.c:4370
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:340
 generic_shutdown_super+0x2bb/0x660 fs/super.c:465
 kill_anon_super+0x63/0xb0 fs/super.c:1057
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2348
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x19e/0x1a0 fs/super.c:366
 cleanup_mnt+0x797/0x870 fs/namespace.c:1137
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1144
 task_work_run+0x1f0/0x2c0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x3fc/0x490 kernel/entry/common.c:176
 exit_to_user_mode_prepare kernel/entry/common.c:208 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x80/0xc0 kernel/entry/common.c:302
 __do_fast_syscall_32+0xa5/0xf0 arch/x86/entry/common.c:183
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
=====================================================