syzbot


WARNING in kcov_task_exit

Status: upstream: reported on 2025/10/05 04:48
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+47cf95ca1f9dcca872c8@syzkaller.appspotmail.com
First crash: 224d, last: now
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
523e8a01-7718-4f4b-9347-0dc94cdedb36 repro WARNING in kcov_task_exit 2026/03/07 12:39 2026/03/07 12:39 2026/03/07 12:49 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] kcov: fix potential kcov_mode corruption under CONFIG_PREEMPT_RT 3 (3) 2026/05/09 08:09
[syzbot] [kernel?] WARNING in kcov_task_exit 0 (1) 2025/10/05 04:48

Sample crash report:
------------[ cut here ]------------
kcov->t != t
WARNING: kernel/kcov.c:483 at kcov_task_exit+0xf5/0x160 kernel/kcov.c:483, CPU#1: syz.3.2417/13312
Modules linked in:
CPU: 1 UID: 0 PID: 13312 Comm: syz.3.2417 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:kcov_task_exit+0xf5/0x160 kernel/kcov.c:483
Code: 10 00 00 48 8b bb 90 00 00 00 e8 36 b3 55 00 48 89 df 5b 41 5e 41 5f e9 29 70 5b 00 7c 1c 5b 41 5e 41 5f e9 8d 1b 5c 09 cc 90 <0f> 0b 90 4c 89 f7 5b 41 5e 41 5f e9 9b b3 5a 09 48 89 df be 03 00
RSP: 0018:ffffc900064dfd20 EFLAGS: 00010206
RAX: 15d0c6e583c2fd00 RBX: ffff88801dec9f00 RCX: 0000000000000000
RDX: 00000000e0899ed9 RSI: ffffffff8ba74fc0 RDI: 00000000ffffffff
RBP: ffffc900064dfe78 R08: ffffffff8b1f2900 R09: ffffffff8dfc8140
R10: dffffc0000000000 R11: fffffbfff1f11dff R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88801dec9f08 R15: ffff888020bd0000
FS:  00005555646df500(0000) GS:ffff888126276000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555cfdf9f8 CR3: 000000007741e000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 do_exit+0x150/0x22c0 kernel/exit.c:908
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
 __do_sys_exit_group kernel/exit.c:1129 [inline]
 __se_sys_exit_group kernel/exit.c:1127 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1127
 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbebfffce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdd24353d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbebfffce59
RDX: 00007fbebf259000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffdd243543c R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000020e
R13: 00000000000927c0 R14: 00000000000bbb34 R15: 00007ffdd2435490
 </TASK>

Crashes (11065):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/13 08:36 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/13 06:29 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/13 05:19 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/13 04:05 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/13 00:32 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 20:26 upstream c21b90f77687 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 19:01 upstream c21b90f77687 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 17:40 upstream 50897c955902 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 16:01 upstream 50897c955902 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 10:41 upstream 50897c955902 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 10:38 upstream 50897c955902 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 08:02 upstream 50897c955902 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 06:28 upstream 50897c955902 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/12 05:20 upstream 50897c955902 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/11 19:26 upstream 5d6919055dec e6eb7c0b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/11 18:09 upstream 5d6919055dec e6eb7c0b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/03/07 12:25 upstream 651690480a96 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2025/10/04 19:59 upstream cbf33b8e0b36 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2025/10/01 04:45 upstream 50c19e20ed2e 65a0eece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in kcov_task_exit
2026/05/13 10:35 linux-next e98d21c170b0 fec2a7ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/13 09:36 linux-next e98d21c170b0 fec2a7ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/13 07:24 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/13 05:28 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/13 02:48 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/13 01:49 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/13 00:14 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 23:06 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 22:29 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 21:27 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/12 21:27 linux-next e98d21c170b0 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/12 20:07 linux-next e98d21c170b0 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/12 16:38 linux-next e98d21c170b0 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 14:58 linux-next e98d21c170b0 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 13:46 linux-next e98d21c170b0 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 13:11 linux-next e98d21c170b0 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 11:51 linux-next e98d21c170b0 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 09:04 linux-next e98d21c170b0 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/12 07:01 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 04:10 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 03:04 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/12 02:00 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/12 01:12 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/12 00:11 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
2026/05/11 22:39 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/11 22:34 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/11 21:34 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in kcov_task_exit
2026/05/11 20:19 linux-next e98d21c170b0 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in kcov_task_exit
* Struck through repros no longer work on HEAD.