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BUG: KMSAN: uninit-value in iov_iter_alignment_iovec+0x19e/0x470 lib/iov_iter.c:894
 iov_iter_alignment_iovec+0x19e/0x470 lib/iov_iter.c:894
 iov_iter_alignment+0x174/0x2d0 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+0x204/0xa20 fs/btrfs/direct-io.c:1026
 btrfs_file_read_iter+0xce/0x310 fs/btrfs/file.c:3657
 aio_read+0x490/0x6b0 fs/aio.c:1602
 __io_submit_one fs/aio.c:-1 [inline]
 io_submit_one+0x25a2/0x3420 fs/aio.c:2052
 __do_sys_io_submit fs/aio.c:2111 [inline]
 __se_sys_io_submit+0x27c/0x6a0 fs/aio.c:2081
 __x64_sys_io_submit+0x97/0xe0 fs/aio.c:2081
 x64_sys_call+0x12c8/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:210
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 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:1583
 __io_submit_one fs/aio.c:-1 [inline]
 io_submit_one+0x25a2/0x3420 fs/aio.c:2052

CPU: 1 UID: 0 PID: 9451 Comm: syz.6.886 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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