syzbot


WARNING in kcov_remote_start

Status: upstream: reported on 2026/05/22 01:58
Reported-by: syzbot+a0da97bbf72cfbc5a796@syzkaller.appspotmail.com
First crash: 4d06h, last: 4d06h
Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in kcov_remote_start (2) -1 1 89d 89d 0/3 upstream: reported on 2026/02/26 04:25
linux-5.15 WARNING in kcov_remote_start -1 4 501d 600d 0/3 auto-obsoleted due to no activity on 2025/04/19 19:40
upstream WARNING in kcov_remote_start (4) usb -1 107983 685d 715d 26/29 fixed on 2024/07/10 08:24
upstream WARNING in kcov_remote_start (2) usb -1 C 1153 2456d 2456d 0/29 closed as invalid on 2019/09/04 14:27
upstream WARNING in kcov_remote_start (5) wireless -1 4243 581d 680d 28/29 fixed on 2024/10/22 14:56
upstream WARNING in kcov_remote_start (3) usb -1 265513 719d 788d 25/29 fixed on 2024/06/05 13:52
upstream WARNING in kcov_remote_start usb -1 C 655 2456d 2456d 0/29 closed as invalid on 2019/09/03 16:37
upstream WARNING in kcov_remote_start (6) kernel prio:low -1 25314 5m 567d 0/29 upstream: reported on 2024/11/04 21:25
linux-6.1 WARNING in kcov_remote_start -1 10 10d 331d 0/3 upstream: reported on 2025/06/28 15:34

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 17041 at kernel/kcov.c:870 arch_local_irq_restore arch/x86/include/asm/irqflags.h:138 [inline]
WARNING: CPU: 0 PID: 17041 at kernel/kcov.c:870 kcov_remote_start+0x551/0x7e0 kernel/kcov.c:888
Modules linked in:
CPU: 0 PID: 17041 Comm: syz.0.3779 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:kcov_remote_start+0x551/0x7e0 kernel/kcov.c:870
Code: ff ff 4c 89 ff be 03 00 00 00 e8 ba 13 a3 02 e9 f0 fa ff ff e8 30 b6 ff 08 f7 c3 00 02 00 00 0f 84 df fa ff ff e9 5a fc ff ff <0f> 0b e8 08 cb ff 08 89 c0 48 c7 c7 00 c3 02 00 48 03 3c c5 30 9a
RSP: 0018:ffffc9000c67f470 EFLAGS: 00010002
RAX: 0000000080000200 RBX: 0000000000000246 RCX: 0000000000000002
RDX: 0000000000000002 RSI: ffffffff8acadd60 RDI: ffffffff8b1c9860
RBP: ffffc9000c67f710 R08: dffffc0000000000 R09: 1ffffffff2238ead
R10: dffffc0000000000 R11: fffffbfff2238eae R12: ffff8880b8e2c300
R13: ffffffff8187301f R14: ffff888022f3bc00 R15: 0000000000000000
FS:  00007fbe0e4726c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff71ecb9440 CR3: 0000000075708000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 kcov_remote_start_common include/linux/kcov.h:50 [inline]
 ieee80211_rx_list+0x813/0x32d0 net/mac80211/rx.c:5419
 ieee80211_rx_napi+0x1b2/0x3d0 net/mac80211/rx.c:5460
 ieee80211_rx include/net/mac80211.h:4971 [inline]
 ieee80211_handle_queued_frames+0x106/0x1a0 net/mac80211/main.c:319
 ieee80211_stop_device+0x2b/0xa0 net/mac80211/util.c:2331
 ieee80211_do_stop+0x1707/0x1e20 net/mac80211/iface.c:748
 ieee80211_stop+0x436/0x4a0 net/mac80211/iface.c:807
 __dev_close_many+0x1d5/0x2b0 net/core/dev.c:1603
 __dev_close net/core/dev.c:1615 [inline]
 __dev_change_flags+0x2dc/0x6a0 net/core/dev.c:8721
 dev_change_flags+0x88/0x1a0 net/core/dev.c:8795
 dev_ioctl+0x7b4/0x1140 net/core/dev_ioctl.c:770
 sock_do_ioctl+0x239/0x310 net/socket.c:1233
 sock_ioctl+0x5ba/0x7e0 net/socket.c:1340
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbe0d59ce59
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:00007fbe0e472028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fbe0d815fa0 RCX: 00007fbe0d59ce59
RDX: 0000200000000080 RSI: 0000000000008914 RDI: 0000000000000007
RBP: 00007fbe0d632d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbe0d816038 R14: 00007fbe0d815fa0 R15: 00007ffe55c71768
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/22 01:58 linux-6.6.y eac8889a3a1c 70ae9b03 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf WARNING in kcov_remote_start
* Struck through repros no longer work on HEAD.