syzbot

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BUG: KCSAN: data-race in snd_pcm_oss_ioctl / snd_pcm_oss_set_trigger

write to 0xffff88802d552300 of 1 bytes by task 13358 on cpu 0:
 snd_pcm_oss_set_trigger+0x2c3/0x490 sound/core/oss/pcm_oss.c:2098
 snd_pcm_oss_poll+0x429/0x510 sound/core/oss/pcm_oss.c:2841
 vfs_poll include/linux/poll.h:90 [inline]
 do_select+0x8b1/0xfc0 fs/select.c:534
 core_sys_select+0x408/0x690 fs/select.c:677
 do_pselect fs/select.c:759 [inline]
 __do_sys_pselect6+0x1bf/0x220 fs/select.c:800
 __se_sys_pselect6 fs/select.c:791 [inline]
 __x64_sys_pselect6+0x74/0x80 fs/select.c:791
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88802d552300 of 1 bytes by task 13368 on cpu 1:
 snd_pcm_oss_get_ptr sound/core/oss/pcm_oss.c:2174 [inline]
 snd_pcm_oss_ioctl+0xd7f/0x2940 sound/core/oss/pcm_oss.c:2693
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 13368 Comm: syz-executor.5 Not tainted 5.11.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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