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BUG: KCSAN: data-race in __wb_update_bandwidth / percpu_counter_add_batch

read-write to 0xffff888100fad148 of 8 bytes by interrupt on cpu 1:
 percpu_counter_add_batch+0xc9/0x140 lib/percpu_counter.c:96
 wb_stat_mod include/linux/backing-dev.h:66 [inline]
 __wb_writeout_add+0x45/0x1d0 mm/page-writeback.c:583
 __folio_end_writeback+0x215/0x4a0 mm/page-writeback.c:3042
 folio_end_writeback+0x74/0x1f0 mm/filemap.c:1632
 mpage_write_end_io+0x281/0x3a0 fs/mpage.c:72
 bio_endio+0x369/0x410 block/bio.c:1636
 blk_update_request+0x382/0x880 block/blk-mq.c:929
 blk_mq_end_request+0x26/0x50 block/blk-mq.c:1057
 lo_complete_rq+0xce/0x180 drivers/block/loop.c:389
 blk_complete_reqs block/blk-mq.c:1132 [inline]
 blk_done_softirq+0x74/0xb0 block/blk-mq.c:1137
 handle_softirqs+0xc3/0x280 kernel/softirq.c:554
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:928
 smpboot_thread_fn+0x31c/0x4c0 kernel/smpboot.c:164
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff888100fad148 of 8 bytes by task 4076 on cpu 0:
 percpu_counter_read include/linux/percpu_counter.h:110 [inline]
 __wb_update_bandwidth+0x9b/0x5d0 mm/page-writeback.c:1484
 wb_update_bandwidth mm/page-writeback.c:1511 [inline]
 do_writepages+0x443/0x480 mm/page-writeback.c:2660
 filemap_fdatawrite_wbc+0xdb/0x100 mm/filemap.c:397
 __filemap_fdatawrite_range mm/filemap.c:430 [inline]
 file_write_and_wait_range+0xc8/0x170 mm/filemap.c:788
 __generic_file_fsync+0x4c/0x140 fs/libfs.c:1516
 fat_file_fsync+0x4c/0x100 fs/fat/file.c:191
 vfs_fsync_range+0x122/0x140 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2794 [inline]
 generic_file_write_iter+0x191/0x1d0 mm/filemap.c:4140
 do_iter_readv_writev+0x339/0x3e0
 vfs_writev+0x2e4/0x890 fs/read_write.c:971
 do_pwritev fs/read_write.c:1072 [inline]
 __do_sys_pwritev fs/read_write.c:1119 [inline]
 __se_sys_pwritev fs/read_write.c:1114 [inline]
 __x64_sys_pwritev+0x100/0x1c0 fs/read_write.c:1114
 x64_sys_call+0x2a3d/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:297
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000030 -> 0x0000000000000040

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4076 Comm: syz.3.268 Not tainted 6.10.0-rc5-syzkaller-00280-g27b31deb900d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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