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KCSAN: data-race in __mpage_writepage / generic_write_end (7)

Status: auto-obsoleted due to no activity on 2023/06/19 15:13
Subsystems: exfat
[Documentation on labels]
First crash: 341d, last: 341d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __mpage_writepage / generic_write_end exfat 7 1405d 1436d 0/26 closed as invalid on 2020/06/18 14:13
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (8) exfat 1 300d 300d 0/26 auto-obsoleted due to no activity on 2023/07/30 18:33
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (2) exfat 9 1324d 1389d 0/26 auto-closed as invalid on 2020/10/09 21:50
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (5) exfat 1 714d 714d 0/26 auto-closed as invalid on 2022/06/11 23:17
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (6) exfat 4 398d 476d 0/26 auto-obsoleted due to no activity on 2023/04/23 23:08
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (3) exfat 1 1234d 1230d 0/26 auto-closed as invalid on 2021/01/07 12:23
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (9) exfat 47 78d 134d 0/26 auto-obsoleted due to no activity on 2024/03/08 15:44
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (4) exfat 2 771d 805d 0/26 auto-closed as invalid on 2022/04/16 04:47

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __mpage_writepage / generic_write_end

write to 0xffff888109b17ce8 of 8 bytes by task 4847 on cpu 0:
 i_size_write include/linux/fs.h:905 [inline]
 generic_write_end+0xb4/0x360 fs/buffer.c:2241
 fat_write_end+0x4e/0x160 fs/fat/inode.c:244
 generic_perform_write+0x253/0x3d0 mm/filemap.c:3934
 __generic_file_write_iter+0xe6/0x290 mm/filemap.c:4051
 generic_file_write_iter+0x7d/0x1c0 mm/filemap.c:4083
 do_iter_write+0x4ae/0x770 fs/read_write.c:860
 vfs_iter_write+0x50/0x70 fs/read_write.c:901
 iter_file_splice_write+0x456/0x7d0 fs/splice.c:795
 do_splice_from fs/splice.c:873 [inline]
 direct_splice_actor+0x84/0xa0 fs/splice.c:1039
 splice_direct_to_actor+0x2ee/0x5f0 fs/splice.c:994
 do_splice_direct+0x104/0x180 fs/splice.c:1082
 do_sendfile+0x3b8/0x950 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888109b17ce8 of 8 bytes by task 34 on cpu 1:
 i_size_read include/linux/fs.h:883 [inline]
 __mpage_writepage+0xc3/0xdb0 fs/mpage.c:489
 write_cache_pages+0x3a1/0x760 mm/page-writeback.c:2473
 mpage_writepages+0x72/0xe0 fs/mpage.c:679
 fat_writepages+0x24/0x30 fs/fat/inode.c:200
 do_writepages+0x1c5/0x340 mm/page-writeback.c:2551
 __writeback_single_inode+0x91/0x860 fs/fs-writeback.c:1603
 writeback_sb_inodes+0x511/0xaa0 fs/fs-writeback.c:1894
 wb_writeback+0x23b/0x6c0 fs/fs-writeback.c:2068
 wb_do_writeback fs/fs-writeback.c:2211 [inline]
 wb_workfn+0x1a8/0x8d0 fs/fs-writeback.c:2251
 process_one_work+0x3e6/0x750 kernel/workqueue.c:2405
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2552
 kthread+0x1d7/0x210 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

value changed: 0x00000000002f2000 -> 0x00000000002f2278

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 34 Comm: kworker/u4:2 Not tainted 6.4.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
Workqueue: writeback wb_workfn (flush-7:3)
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/15 09:10 upstream f1fcbaa18b28 f1743960 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __mpage_writepage / generic_write_end
* Struck through repros no longer work on HEAD.