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BUG: KMSAN: uninit-value in btrfs_clean_tree_block+0x28d/0x330 fs/btrfs/disk-io.c:1007
CPU: 1 PID: 9567 Comm: syz-executor.3 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197
 btrfs_clean_tree_block+0x28d/0x330 fs/btrfs/disk-io.c:1007
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4684 [inline]
 btrfs_alloc_tree_block+0x999/0x1f40 fs/btrfs/extent-tree.c:4762
 alloc_tree_block_no_bg_flush fs/btrfs/ctree.c:989 [inline]
 __btrfs_cow_block+0xb28/0x2490 fs/btrfs/ctree.c:1045
 btrfs_cow_block+0xa36/0xca0 fs/btrfs/ctree.c:1497
 commit_cowonly_roots+0x1cb/0x1620 fs/btrfs/transaction.c:1186
 btrfs_commit_transaction+0x2415/0x5780 fs/btrfs/transaction.c:2283
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4023
 close_ctree+0x46a/0xd8f fs/btrfs/disk-io.c:4087
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:321
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1108
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2263
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1118
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1125
 task_work_run+0x140/0x280 kernel/task_work.c:151
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
 exit_to_user_mode_prepare+0x3c9/0x490 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x35/0x50 kernel/entry/common.c:266
 __do_fast_syscall_32+0x12d/0x160 arch/x86/entry/common.c:80
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7fa0549
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000ffee961c EFLAGS: 00000292 ORIG_RAX: 0000000000000034
RAX: 0000000000000000 RBX: 00000000ffee96ac RCX: 0000000000000002
RDX: 0000000009488228 RSI: 000000000948828c RDI: 00000000080d8fe2
RBP: 00000000ffee96ac R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:121
 kmsan_alloc_page+0xd3/0x1f0 mm/kmsan/kmsan_shadow.c:274
 __alloc_pages_nodemask+0x827/0xf90 mm/page_alloc.c:4989
 alloc_pages_current+0x7b6/0xb60 mm/mempolicy.c:2271
 alloc_pages include/linux/gfp.h:547 [inline]
 __page_cache_alloc mm/filemap.c:977 [inline]
 pagecache_get_page+0x1127/0x2070 mm/filemap.c:1828
 find_or_create_page include/linux/pagemap.h:404 [inline]
 alloc_extent_buffer+0x7ae/0x27d0 fs/btrfs/extent_io.c:5209
 btrfs_find_create_tree_block+0x68/0x80 fs/btrfs/disk-io.c:972
 btrfs_init_new_buffer fs/btrfs/extent-tree.c:4665 [inline]
 btrfs_alloc_tree_block+0x50d/0x1f40 fs/btrfs/extent-tree.c:4762
 alloc_tree_block_no_bg_flush fs/btrfs/ctree.c:989 [inline]
 __btrfs_cow_block+0xb28/0x2490 fs/btrfs/ctree.c:1045
 btrfs_cow_block+0xa36/0xca0 fs/btrfs/ctree.c:1497
 commit_cowonly_roots+0x1cb/0x1620 fs/btrfs/transaction.c:1186
 btrfs_commit_transaction+0x2415/0x5780 fs/btrfs/transaction.c:2283
 btrfs_commit_super+0x1b7/0x1f0 fs/btrfs/disk-io.c:4023
 close_ctree+0x46a/0xd8f fs/btrfs/disk-io.c:4087
 btrfs_put_super+0x53/0x70 fs/btrfs/super.c:321
 generic_shutdown_super+0x2ab/0x650 fs/super.c:464
 kill_anon_super+0x63/0xb0 fs/super.c:1108
 btrfs_kill_super+0x61/0x90 fs/btrfs/super.c:2263
 deactivate_locked_super+0x10d/0x1e0 fs/super.c:335
 deactivate_super+0x1b7/0x1d0 fs/super.c:366
 cleanup_mnt+0x7a0/0x870 fs/namespace.c:1118
 __cleanup_mnt+0x3b/0x50 fs/namespace.c:1125
 task_work_run+0x140/0x280 kernel/task_work.c:151
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
 exit_to_user_mode_prepare+0x3c9/0x490 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x35/0x50 kernel/entry/common.c:266
 __do_fast_syscall_32+0x12d/0x160 arch/x86/entry/common.c:80
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
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