BTRFS info (device loop1): enabling free space tree
=====================================================
BUG: KMSAN: uninit-value in iov_iter_alignment_iovec+0x19e/0x470 lib/iov_iter.c:808
 iov_iter_alignment_iovec+0x19e/0x470 lib/iov_iter.c:808
 iov_iter_alignment+0x174/0x2d0 lib/iov_iter.c:853
 check_direct_IO fs/btrfs/direct-io.c:786 [inline]
 check_direct_read fs/btrfs/direct-io.c:1008 [inline]
 btrfs_direct_read+0x2eb/0xcb0 fs/btrfs/direct-io.c:1037
 btrfs_file_read_iter+0x204/0x430 fs/btrfs/file.c:3831
 aio_read+0x493/0x6b0 fs/aio.c:1603
 __io_submit_one fs/aio.c:-1 [inline]
 io_submit_one+0x25d6/0x3450 fs/aio.c:2053
 __do_sys_io_submit fs/aio.c:2112 [inline]
 __se_sys_io_submit+0x27c/0x6a0 fs/aio.c:2082
 __x64_sys_io_submit+0x97/0xe0 fs/aio.c:2082
 x64_sys_call+0x3b5f/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:210
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable inline_vecs created at:
 aio_read+0x4f/0x6b0 fs/aio.c:1584
 __io_submit_one fs/aio.c:-1 [inline]
 io_submit_one+0x25d6/0x3450 fs/aio.c:2053

CPU: 1 UID: 0 PID: 6126 Comm: syz.1.39 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
=====================================================