syzbot

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BUG: KCSAN: data-race in snd_pcm_oss_make_ready_locked / snd_pcm_oss_poll

write to 0xffff88809c0bff00 of 1 bytes by task 14311 on cpu 0:
 snd_pcm_oss_poll+0x40e/0x5f0 sound/core/oss/pcm_oss.c:2830
 vfs_poll include/linux/poll.h:90 [inline]
 do_select+0x7cf/0x1020 fs/select.c:534
 core_sys_select+0x2c7/0x5f0 fs/select.c:677
 do_pselect.constprop.0+0x125/0x160 fs/select.c:759
 __do_sys_pselect6 fs/select.c:784 [inline]
 __se_sys_pselect6 fs/select.c:769 [inline]
 __x64_sys_pselect6+0x12a/0x160 fs/select.c:769
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88809c0bff00 of 1 bytes by task 14309 on cpu 1:
 snd_pcm_oss_make_ready_locked+0x3c/0xe0 sound/core/oss/pcm_oss.c:1165
 snd_pcm_oss_read1 sound/core/oss/pcm_oss.c:1494 [inline]
 snd_pcm_oss_read+0x26d/0x510 sound/core/oss/pcm_oss.c:2742
 __vfs_read+0x58/0xb0 fs/read_write.c:426
 vfs_read fs/read_write.c:462 [inline]
 vfs_read+0x13e/0x2b0 fs/read_write.c:447
 ksys_read+0xc5/0x1a0 fs/read_write.c:588
 __do_sys_read fs/read_write.c:598 [inline]
 __se_sys_read fs/read_write.c:596 [inline]
 __x64_sys_read+0x49/0x60 fs/read_write.c:596
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 14309 Comm: syz-executor.0 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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