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BUG: KMSAN: uninit-value in iov_iter_alignment_iovec+0x1a8/0x470 lib/iov_iter.c:894
 iov_iter_alignment_iovec+0x1a8/0x470 lib/iov_iter.c:894
 iov_iter_alignment+0x1ac/0x2d0 lib/iov_iter.c:939
 check_direct_IO fs/btrfs/direct-io.c:787 [inline]
 check_direct_read fs/btrfs/direct-io.c:997 [inline]
 btrfs_direct_read+0x20b/0x9c0 fs/btrfs/direct-io.c:1026
 btrfs_file_read_iter+0xe3/0x2d0 fs/btrfs/file.c:3652
 aio_read+0x4b2/0x690 fs/aio.c:1602
 __io_submit_one fs/aio.c:-1 [inline]
 io_submit_one+0x2804/0x3280 fs/aio.c:2052
 __do_sys_io_submit fs/aio.c:2111 [inline]
 __se_sys_io_submit+0x275/0x700 fs/aio.c:2081
 __x64_sys_io_submit+0x96/0xe0 fs/aio.c:2081
 x64_sys_call+0xbed/0x3c80 arch/x86/include/generated/asm/syscalls_64.h:210
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable inline_vecs created at:
 aio_read+0x4c/0x690 fs/aio.c:1583
 __io_submit_one fs/aio.c:-1 [inline]
 io_submit_one+0x2804/0x3280 fs/aio.c:2052

CPU: 1 UID: 0 PID: 6839 Comm: syz-executor Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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