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KCSAN: data-race in nr_blockdev_pages / page_cache_delete_batch (3)

Status: auto-obsoleted due to no activity on 2022/10/27 09:21
Subsystems: block
[Documentation on labels]
First crash: 1084d, last: 1073d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in nr_blockdev_pages / page_cache_delete_batch (2) block 6 4 1138d 1189d 0/29 auto-closed as invalid on 2022/08/23 18:22
upstream KCSAN: data-race in nr_blockdev_pages / page_cache_delete_batch block 6 1 1230d 1230d 0/29 auto-closed as invalid on 2022/05/23 16:48

Sample crash report:
==================================================================
BUG: KCSAN: data-race in nr_blockdev_pages / page_cache_delete_batch

read-write to 0xffff8881023d7648 of 8 bytes by task 13044 on cpu 1:
 page_cache_delete_batch+0x445/0x470 mm/filemap.c:315
 delete_from_page_cache_batch+0x18f/0x2a0 mm/filemap.c:334
 truncate_inode_pages_range+0x3ca/0xae0 mm/truncate.c:370
 truncate_inode_pages+0x20/0x30 mm/truncate.c:452
 kill_bdev block/bdev.c:75 [inline]
 set_blocksize+0x24e/0x270 block/bdev.c:151
 sb_set_blocksize+0x2c/0xa0 block/bdev.c:160
 __ext4_fill_super fs/ext4/super.c:4753 [inline]
 ext4_fill_super+0x228b/0x5010 fs/ext4/super.c:5517
 get_tree_bdev+0x2b4/0x3b0 fs/super.c:1323
 ext4_get_tree+0x18/0x20 fs/ext4/super.c:5547
 vfs_get_tree+0x49/0x190 fs/super.c:1530
 do_new_mount+0x200/0x650 fs/namespace.c:3040
 path_mount+0x4ad/0xbb0 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x281/0x2d0 fs/namespace.c:3568
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881023d7648 of 8 bytes by task 27245 on cpu 0:
 nr_blockdev_pages+0x7f/0xd0 block/bdev.c:522
 si_meminfo+0x3a/0x60 mm/page_alloc.c:5924
 update_defense_level+0x46/0x560 net/netfilter/ipvs/ip_vs_ctl.c:102
 defense_work_handler+0x1b/0x80 net/netfilter/ipvs/ip_vs_ctl.c:236
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

value changed: 0x0000000000000001 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 27245 Comm: kworker/0:2 Not tainted 6.0.0-rc6-syzkaller-00030-g06f7db949993-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2022
Workqueue: events_long defense_work_handler
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/09/22 09:20 upstream 06f7db949993 60af5050 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in nr_blockdev_pages / page_cache_delete_batch
2022/09/12 03:20 upstream 4ed9c1e971b1 356d8217 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in nr_blockdev_pages / page_cache_delete_batch
* Struck through repros no longer work on HEAD.