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KCSAN: data-race in __delete_from_page_cache / ext4_writepages

Status: auto-closed as invalid on 2020/06/18 13:43
Subsystems: iomap
[Documentation on labels]
First crash: 1569d, last: 1454d
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __delete_from_page_cache / ext4_writepages (3) iomap 68 1067d 1234d 0/26 auto-closed as invalid on 2021/06/27 20:06
upstream KCSAN: data-race in __delete_from_page_cache / ext4_writepages (4) iomap 8 878d 937d 0/26 auto-closed as invalid on 2022/01/02 10:49
upstream KCSAN: data-race in __delete_from_page_cache / ext4_writepages (2) iomap 3 1397d 1405d 0/26 auto-closed as invalid on 2020/08/01 18:05

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __delete_from_page_cache / ext4_writepages

write to 0xffff888113d90380 of 8 bytes by task 2065 on cpu 1:
 page_cache_delete mm/filemap.c:153 [inline]
 __delete_from_page_cache+0x1e4/0x490 mm/filemap.c:238
 invalidate_complete_page2 mm/truncate.c:651 [inline]
 invalidate_inode_pages2_range+0x6ad/0xab0 mm/truncate.c:744
 iomap_dio_rw+0x540/0x9a0 fs/iomap/direct-io.c:481
 ext4_dio_write_iter fs/ext4/file.c:532 [inline]
 ext4_file_write_iter+0xb84/0xd30 fs/ext4/file.c:640
 call_write_iter include/linux/fs.h:1907 [inline]
 do_iter_readv_writev+0x4a7/0x5d0 fs/read_write.c:694
 do_iter_write fs/read_write.c:999 [inline]
 do_iter_write+0x137/0x3a0 fs/read_write.c:980
 vfs_iter_write+0x56/0x80 fs/read_write.c:1040
 iter_file_splice_write+0x530/0x830 fs/splice.c:760
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x97/0xb0 fs/splice.c:1037
 splice_direct_to_actor+0x22f/0x540 fs/splice.c:992
 do_splice_direct+0x152/0x1d0 fs/splice.c:1080
 do_sendfile+0x380/0x800 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0x121/0x140 fs/read_write.c:1568
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888113d90380 of 8 bytes by task 2067 on cpu 0:
 ext4_writepages+0x186/0x1e10 fs/ext4/inode.c:2637
 do_writepages+0x6b/0x170 mm/page-writeback.c:2344
 __filemap_fdatawrite_range+0x1bb/0x220 mm/filemap.c:421
 file_write_and_wait_range+0xfb/0x160 mm/filemap.c:760
 ext4_sync_file+0x26e/0x8b0 fs/ext4/fsync.c:153
 vfs_fsync_range+0x7c/0x150 fs/sync.c:197
 generic_write_sync include/linux/fs.h:2872 [inline]
 ext4_buffered_write_iter+0x211/0x280 fs/ext4/file.c:277
 ext4_file_write_iter+0xf4/0xd30 fs/ext4/file.c:642
 call_write_iter include/linux/fs.h:1907 [inline]
 do_iter_readv_writev+0x4a7/0x5d0 fs/read_write.c:694
 do_iter_write fs/read_write.c:999 [inline]
 do_iter_write+0x137/0x3a0 fs/read_write.c:980
 vfs_iter_write+0x56/0x80 fs/read_write.c:1040
 iter_file_splice_write+0x530/0x830 fs/splice.c:760
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x97/0xb0 fs/splice.c:1037
 splice_direct_to_actor+0x22f/0x540 fs/splice.c:992
 do_splice_direct+0x152/0x1d0 fs/splice.c:1080
 do_sendfile+0x380/0x800 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1576 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0xb8/0x140 fs/read_write.c:1568
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2067 Comm: syz-executor.3 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/01 09:34 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 143a10e9 .config console log report ci2-upstream-kcsan-gce
2020/04/30 01:40 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 2dd552a5 .config console log report ci2-upstream-kcsan-gce
2020/04/20 14:19 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 347a5dc3 .config console log report ci2-upstream-kcsan-gce
2020/03/08 14:09 https://github.com/google/ktsan.git kcsan 941e0d917bbf 2e9971bb .config console log report ci2-upstream-kcsan-gce
2020/02/19 08:04 https://github.com/google/ktsan.git kcsan b12d66a6c34f 135c18aa .config console log report ci2-upstream-kcsan-gce
2020/02/13 20:08 https://github.com/google/ktsan.git kcsan 55121bc1808a e6247653 .config console log report ci2-upstream-kcsan-gce
2020/02/11 08:48 https://github.com/google/ktsan.git kcsan f60f0f543333 084454ae .config console log report ci2-upstream-kcsan-gce
2020/01/24 02:55 https://github.com/google/ktsan.git kcsan 245a43005292 11ebf937 .config console log report ci2-upstream-kcsan-gce
2020/01/19 21:42 https://github.com/google/ktsan.git kcsan 245a43005292 0342f8c7 .config console log report ci2-upstream-kcsan-gce
2020/01/07 13:29 https://github.com/google/ktsan.git kcsan 245a43005292 1bcd407e .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.