protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
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BUG: KCSAN: data-race in fprop_fraction_percpu / percpu_counter_add_batch

read to 0xffff8881251099e8 of 8 bytes by task 16235 on cpu 0:
 fprop_fraction_percpu+0x9c/0x1c0 lib/flex_proportions.c:238
 __wb_calc_thresh+0x6f/0x250 mm/page-writeback.c:775
 wb_dirty_limits mm/page-writeback.c:1531 [inline]
 balance_dirty_pages+0x1187/0x1ba0 mm/page-writeback.c:1693
 balance_dirty_pages_ratelimited+0x752/0xb40 mm/page-writeback.c:1913
 generic_perform_write+0x22d/0x320 mm/filemap.c:3340
 __generic_file_write_iter+0x251/0x380 mm/filemap.c:3433
 ext4_file_write_iter+0x1bd/0xa00 fs/ext4/file.c:268
 call_write_iter include/linux/fs.h:1895 [inline]
 new_sync_write+0x388/0x4a0 fs/read_write.c:483
 __vfs_write+0xb1/0xc0 fs/read_write.c:496
 vfs_write fs/read_write.c:558 [inline]
 vfs_write+0x18a/0x390 fs/read_write.c:542
 ksys_write+0xd5/0x1b0 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x4c/0x60 fs/read_write.c:620
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8881251099e8 of 8 bytes by interrupt on cpu 1:
 percpu_counter_add_batch+0xca/0x150 lib/percpu_counter.c:91
 percpu_counter_add include/linux/percpu_counter.h:55 [inline]
 __fprop_inc_percpu_max+0xb9/0x150 lib/flex_proportions.c:272
 wb_domain_writeout_inc mm/page-writeback.c:581 [inline]
 __wb_writeout_inc mm/page-writeback.c:610 [inline]
 test_clear_page_writeback+0x5c7/0x790 mm/page-writeback.c:2737
 end_page_writeback+0x9e/0x190 mm/filemap.c:1338
 ext4_finish_bio+0x40d/0x520 fs/ext4/page-io.c:110
 ext4_end_bio+0xd2/0x310 fs/ext4/page-io.c:334
 bio_endio+0x3a8/0x4f0 block/bio.c:1818
 req_bio_endio block/blk-core.c:242 [inline]
 blk_update_request+0x427/0x7b0 block/blk-core.c:1462
 scsi_end_request+0x6b/0x3e0 drivers/scsi/scsi_lib.c:579
 scsi_io_completion+0x11d/0xc80 drivers/scsi/scsi_lib.c:963
 scsi_finish_command+0x280/0x380 drivers/scsi/scsi.c:228
 scsi_softirq_done+0x259/0x280 drivers/scsi/scsi_lib.c:1477
 blk_done_softirq+0x1eb/0x250 block/blk-softirq.c:37

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15223 Comm: kworker/u4:1 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfn (flush-8:0)
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