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KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (5)

Status: auto-closed as invalid on 2022/03/11 03:48
Subsystems: ext4
[Documentation on labels]
First crash: 807d, last: 805d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages ext4 3 1051d 1075d 0/26 auto-closed as invalid on 2021/07/08 08:36
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (4) ext4 6 850d 872d 0/26 auto-closed as invalid on 2022/01/24 21:33
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (3) ext4 13 910d 969d 0/26 auto-closed as invalid on 2021/11/26 15:32
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (6) ext4 5 711d 712d 0/26 closed as invalid on 2022/05/13 11:20
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (2) ext4 2 1005d 1009d 0/26 auto-closed as invalid on 2021/08/23 09:16

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages

write to 0xffff8881360a4718 of 8 bytes by task 4493 on cpu 1:
 i_size_write include/linux/fs.h:907 [inline]
 ext4_dio_write_end_io+0xd3/0x100 fs/ext4/file.c:397
 iomap_dio_complete+0xb8/0x3e0 fs/iomap/direct-io.c:78
 iomap_dio_rw+0x56/0x80 fs/iomap/direct-io.c:683
 ext4_dio_write_iter fs/ext4/file.c:564 [inline]
 ext4_file_write_iter+0xab3/0x11f0 fs/ext4/file.c:675
 call_write_iter include/linux/fs.h:2074 [inline]
 do_iter_readv_writev+0x2de/0x380 fs/read_write.c:725
 do_iter_write+0x192/0x5c0 fs/read_write.c:851
 vfs_iter_write+0x4c/0x70 fs/read_write.c:892
 iter_file_splice_write+0x43a/0x790 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881360a4718 of 8 bytes by task 4511 on cpu 0:
 i_size_read include/linux/fs.h:885 [inline]
 ext4_readpage_limit fs/ext4/readpage.c:220 [inline]
 ext4_mpage_readpages+0x385/0xff0 fs/ext4/readpage.c:264
 ext4_readahead+0x99/0xa0 fs/ext4/inode.c:3182
 read_pages+0xba/0x5f0 mm/readahead.c:129
 page_cache_ra_unbounded+0x16a/0x400 mm/readahead.c:210
 ondemand_readahead+0x4f8/0x700
 page_cache_sync_ra+0xaf/0xe0 mm/readahead.c:579
 page_cache_sync_readahead include/linux/pagemap.h:1056 [inline]
 filemap_get_pages mm/filemap.c:2589 [inline]
 filemap_read+0x3ed/0x1430 mm/filemap.c:2676
 generic_file_read_iter+0x72/0x320 mm/filemap.c:2822
 ext4_file_read_iter+0x1db/0x290
 call_read_iter include/linux/fs.h:2068 [inline]
 generic_file_splice_read+0x24f/0x330 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000429000 -> 0x0000000000438000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4511 Comm: syz-executor.2 Not tainted 5.17.0-rc2-syzkaller-00064-gc36c04c2e132 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/04 03:43 upstream c36c04c2e132 30646bfe .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
2022/02/01 22:50 upstream 9f7fb8de5d9b 4ebb2798 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
* Struck through repros no longer work on HEAD.