KCSAN: data-race in osq_lock / osq

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in osq_lock / osq_lock mm	6				26	2117d	2136d	0/29	closed as invalid on 2019/11/19 14:54
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BUG: KCSAN: data-race in osq_lock / osq_lock

read to 0xffff88812c12d3d4 of 4 bytes by task 23304 on cpu 0:
 osq_lock+0x170/0x2f0 kernel/locking/osq_lock.c:143
 rwsem_optimistic_spin+0x5f/0x320 kernel/locking/rwsem.c:800
 rwsem_down_write_slowpath+0x109/0x950 kernel/locking/rwsem.c:1150
 __down_write kernel/locking/rwsem.c:1392 [inline]
 down_write+0x88/0x90 kernel/locking/rwsem.c:1535
 i_mmap_lock_write include/linux/fs.h:526 [inline]
 __vma_adjust+0x196/0x11d0 mm/mmap.c:809
 vma_adjust include/linux/mm.h:2261 [inline]
 __split_vma+0x338/0x350 mm/mmap.c:2682
 split_vma+0x73/0xa0 mm/mmap.c:2714
 mprotect_fixup+0x3e8/0x510 mm/mprotect.c:407
 do_mprotect_pkey+0x3eb/0x660 mm/mprotect.c:553
 __do_sys_mprotect mm/mprotect.c:578 [inline]
 __se_sys_mprotect mm/mprotect.c:575 [inline]
 __x64_sys_mprotect+0x51/0x70 mm/mprotect.c:575
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff88812c12d3d4 of 4 bytes by task 23334 on cpu 1:
 osq_lock+0x89/0x2f0 kernel/locking/osq_lock.c:99
 rwsem_optimistic_spin+0x5f/0x320 kernel/locking/rwsem.c:800
 rwsem_down_write_slowpath+0x109/0x950 kernel/locking/rwsem.c:1150
 __down_write kernel/locking/rwsem.c:1392 [inline]
 down_write+0x88/0x90 kernel/locking/rwsem.c:1535
 i_mmap_lock_write include/linux/fs.h:526 [inline]
 __vma_adjust+0x196/0x11d0 mm/mmap.c:809
 vma_adjust include/linux/mm.h:2261 [inline]
 __split_vma+0x338/0x350 mm/mmap.c:2682
 split_vma+0x73/0xa0 mm/mmap.c:2714
 mprotect_fixup+0x3e8/0x510 mm/mprotect.c:407
 do_mprotect_pkey+0x3eb/0x660 mm/mprotect.c:553
 __do_sys_mprotect mm/mprotect.c:578 [inline]
 __se_sys_mprotect mm/mprotect.c:575 [inline]
 __x64_sys_mprotect+0x51/0x70 mm/mprotect.c:575
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 23334 Comm: blkid Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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