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KCSAN: data-race in generic_file_direct_write / ondemand_readahead (2)

Status: auto-obsoleted due to no activity on 2023/05/06 18:38
Subsystems: fs
[Documentation on labels]
First crash: 402d, last: 402d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in generic_file_direct_write / ondemand_readahead (3) fs 2 189d 213d 0/26 auto-obsoleted due to no activity on 2023/12/05 20:59
upstream KCSAN: data-race in generic_file_direct_write / ondemand_readahead fs 1 984d 984d 0/26 auto-closed as invalid on 2021/10/01 19:27

Sample crash report:
loop5: detected capacity change from 0 to 2048
==================================================================
BUG: KCSAN: data-race in generic_file_direct_write / ondemand_readahead

write to 0xffff88813ef9dce8 of 8 bytes by task 13066 on cpu 1:
 i_size_write include/linux/fs.h:888 [inline]
 generic_file_direct_write+0x390/0x400 mm/filemap.c:3877
 __generic_file_write_iter+0x122/0x290 mm/filemap.c:4010
 generic_file_write_iter+0x7d/0x1c0 mm/filemap.c:4086
 do_iter_write+0x418/0x700 fs/read_write.c:861
 vfs_iter_write+0x50/0x70 fs/read_write.c:902
 iter_file_splice_write+0x456/0x7d0 fs/splice.c:778
 do_splice_from fs/splice.c:856 [inline]
 direct_splice_actor+0x84/0xa0 fs/splice.c:1022
 splice_direct_to_actor+0x2ee/0x5f0 fs/splice.c:977
 do_splice_direct+0x104/0x180 fs/splice.c:1065
 do_sendfile+0x3b8/0x950 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1309
 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 0xffff88813ef9dce8 of 8 bytes by task 13060 on cpu 0:
 i_size_read include/linux/fs.h:866 [inline]
 do_page_cache_ra mm/readahead.c:287 [inline]
 page_cache_ra_order mm/readahead.c:560 [inline]
 ondemand_readahead+0x4f0/0x6c0 mm/readahead.c:682
 page_cache_sync_ra+0x284/0x2a0 mm/readahead.c:709
 page_cache_sync_readahead include/linux/pagemap.h:1214 [inline]
 filemap_get_pages+0x257/0xea0 mm/filemap.c:2598
 filemap_read+0x223/0x680 mm/filemap.c:2693
 generic_file_read_iter+0x76/0x320 mm/filemap.c:2840
 call_read_iter include/linux/fs.h:1845 [inline]
 generic_file_splice_read+0xe3/0x290 fs/splice.c:402
 do_splice_to fs/splice.c:885 [inline]
 splice_direct_to_actor+0x25a/0x5f0 fs/splice.c:956
 do_splice_direct+0x104/0x180 fs/splice.c:1065
 do_sendfile+0x3b8/0x950 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1309
 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

value changed: 0x000000000000de00 -> 0x000000000000e000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13060 Comm: syz-executor.5 Not tainted 6.3.0-rc4-syzkaller-00199-g7b50567bdcad #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/01 18:30 upstream 7b50567bdcad f325deb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_file_direct_write / ondemand_readahead
* Struck through repros no longer work on HEAD.