=====================================================
BUG: KMSAN: uninit-value in snd_rawmidi_ioctl+0xf08/0x1340 sound/core/rawmidi.c:887
 snd_rawmidi_ioctl+0xf08/0x1340 sound/core/rawmidi.c:887
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0x2df/0x4a0 fs/ioctl.c:860
 __x64_sys_ioctl+0xd8/0x110 fs/ioctl.c:860
 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

Uninit was created at:
 slab_alloc_node mm/slub.c:3228 [inline]
 slab_alloc mm/slub.c:3237 [inline]
 kmem_cache_alloc_trace+0x739/0xfc0 mm/slub.c:3254
 kmalloc include/linux/slab.h:591 [inline]
 snd_rawmidi_open+0x70d/0x1390 sound/core/rawmidi.c:445
 snd_open+0x702/0x890 sound/core/sound.c:169
 chrdev_open+0xc71/0xe00 fs/char_dev.c:414
 do_dentry_open+0x1193/0x1bd0 fs/open.c:822
 vfs_open+0xaf/0xe0 fs/open.c:945
 do_open fs/namei.c:3428 [inline]
 path_openat+0x53d7/0x5eb0 fs/namei.c:3561
 do_filp_open+0x306/0x760 fs/namei.c:3588
 do_sys_openat2+0x263/0x8f0 fs/open.c:1200
 do_sys_open fs/open.c:1216 [inline]
 __do_sys_openat fs/open.c:1232 [inline]
 __se_sys_openat fs/open.c:1227 [inline]
 __x64_sys_openat+0x35f/0x3c0 fs/open.c:1227
 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
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