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BUG: KCSAN: data-race in __filemap_add_folio / nr_blockdev_pages

read-write to 0xffff8881006324b0 of 8 bytes by task 13107 on cpu 0:
 __filemap_add_folio+0x5b5/0x7f0 mm/filemap.c:928
 filemap_add_folio+0x9f/0x1b0 mm/filemap.c:969
 __filemap_get_folio+0x340/0x6b0 mm/filemap.c:1979
 grow_dev_folio fs/buffer.c:1039 [inline]
 grow_buffers fs/buffer.c:1105 [inline]
 __getblk_slow fs/buffer.c:1131 [inline]
 bdev_getblk+0x173/0x3b0 fs/buffer.c:1431
 getblk_unmovable include/linux/buffer_head.h:368 [inline]
 ext4_getblk+0x1bf/0x550 fs/ext4/inode.c:867
 ext4_xattr_inode_write fs/ext4/xattr.c:1413 [inline]
 ext4_xattr_inode_lookup_create+0x934/0xef0 fs/ext4/xattr.c:1594
 ext4_xattr_ibody_set+0x131/0x3b0 fs/ext4/xattr.c:2258
 ext4_xattr_set_handle+0x9a4/0xdb0 fs/ext4/xattr.c:2435
 ext4_xattr_set+0x19b/0x250 fs/ext4/xattr.c:2549
 ext4_xattr_trusted_set+0x3c/0x50 fs/ext4/xattr_trusted.c:38
 __vfs_setxattr+0x2e5/0x310 fs/xattr.c:200
 __vfs_setxattr_noperm+0xed/0x420 fs/xattr.c:234
 __vfs_setxattr_locked+0x1af/0x1d0 fs/xattr.c:295
 vfs_setxattr+0x142/0x290 fs/xattr.c:321
 do_setxattr fs/xattr.c:636 [inline]
 filename_setxattr+0x1ae/0x2b0 fs/xattr.c:665
 path_setxattrat+0x28a/0x320 fs/xattr.c:713
 __do_sys_lsetxattr fs/xattr.c:754 [inline]
 __se_sys_lsetxattr fs/xattr.c:750 [inline]
 __x64_sys_lsetxattr+0x71/0x90 fs/xattr.c:750
 x64_sys_call+0x2014/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:190
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881006324b0 of 8 bytes by task 5169 on cpu 1:
 nr_blockdev_pages+0x7c/0xd0 block/bdev.c:485
 si_meminfo+0x87/0xd0 mm/show_mem.c:80
 update_defense_level+0x4b/0x5c0 net/netfilter/ipvs/ip_vs_ctl.c:102
 defense_work_handler+0x1f/0x80 net/netfilter/ipvs/ip_vs_ctl.c:235
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4de/0xa20 kernel/workqueue.c:3319
 worker_thread+0x52c/0x710 kernel/workqueue.c:3400
 kthread+0x4b7/0x540 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x000000000000000d -> 0x000000000000000e

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5169 Comm: kworker/1:5 Not tainted 6.15.0-rc1-syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_long defense_work_handler
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