=====================================================
BUG: KMSAN: uninit-value in io_fallback_req_func+0x218/0x5f7 fs/io_uring.c:1372
 io_fallback_req_func+0x218/0x5f7 fs/io_uring.c:1372
 process_one_work+0xdb9/0x1820 kernel/workqueue.c:2298
 worker_thread+0x10bc/0x21f0 kernel/workqueue.c:2445
 kthread+0x721/0x850 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:524 [inline]
 kmem_cache_alloc_bulk+0xec5/0x1560 mm/slub.c:3747
 __io_alloc_req_refill+0x482/0x867 fs/io_uring.c:2015
 io_alloc_req_refill fs/io_uring.c:2041 [inline]
 io_submit_sqes+0x88c/0x1040 fs/io_uring.c:7356
 __do_sys_io_uring_enter fs/io_uring.c:10072 [inline]
 __se_sys_io_uring_enter+0x62f/0x23a0 fs/io_uring.c:10014
 __x64_sys_io_uring_enter+0x19d/0x200 fs/io_uring.c:10014
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CPU: 0 PID: 1454 Comm: kworker/0:2 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events io_fallback_req_func
=====================================================