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BUG: KMSAN: uninit-value in tctx_task_work+0x1304/0x1ce0
 tctx_task_work+0x1304/0x1ce0
 task_work_run+0x157/0x290
 get_signal+0x164/0x2d40
 arch_do_signal_or_restart+0x72/0xdd0
 exit_to_user_mode_loop+0x146/0x3b0
 exit_to_user_mode_prepare+0x195/0x240
 syscall_exit_to_user_mode+0x23/0x40
 do_syscall_64+0x49/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was created at:
 kmem_cache_alloc_bulk+0xf3d/0x1550
 __io_alloc_req_refill+0x486/0x882
 io_submit_sqes+0x8de/0x1020
 __se_sys_io_uring_enter+0x887/0x2530
 __x64_sys_io_uring_enter+0x1a1/0x200
 do_syscall_64+0x3d/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CPU: 1 PID: 5937 Comm: syz-executor.4 Not tainted 5.18.0-syzkaller-16253-g2f3064574275 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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