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BUG: KMSAN: uninit-value in iov_iter_alignment_iovec+0x1a8/0x470 lib/iov_iter.c:788
 iov_iter_alignment_iovec+0x1a8/0x470 lib/iov_iter.c:788
 iov_iter_alignment+0x1aa/0x290 lib/iov_iter.c:833
 check_direct_IO fs/btrfs/file.c:1452 [inline]
 check_direct_read fs/btrfs/file.c:3736 [inline]
 btrfs_direct_read fs/btrfs/file.c:3765 [inline]
 btrfs_file_read_iter+0x46f/0xc70 fs/btrfs/file.c:3826
 call_read_iter include/linux/fs.h:2114 [inline]
 aio_read+0x4b3/0x690 fs/aio.c:1611
 io_submit_one+0x2809/0x3280 fs/aio.c:2061
 __do_sys_io_submit fs/aio.c:2120 [inline]
 __se_sys_io_submit+0x275/0x700 fs/aio.c:2090
 __x64_sys_io_submit+0x96/0xe0 fs/aio.c:2090
 x64_sys_call+0x3620/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:210
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable inline_vecs created at:
 aio_read+0x4c/0x690 fs/aio.c:1592
 io_submit_one+0x2809/0x3280 fs/aio.c:2061

CPU: 1 PID: 5053 Comm: syz-executor335 Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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