syzbot


WARNING in wbt_init_enable_default

Status: upstream: reported C repro on 2025/12/25 07:34
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+71fcf20f7c1e5043d78c@syzkaller.appspotmail.com
First crash: 106d, last: 6h16m
Cause bisection: failed (error log, bisect log)
  
Discussions (4)
Title Replies (including bot) Last reply
[PATCH v2] blk-wbt: remove WARN_ON_ONCE from wbt_init_enable_default() 4 (4) 2026/04/04 14:56
[PATCH] blk-wbt: remove WARN_ON_ONCE from wbt_init_enable_default() 3 (3) 2026/03/16 06:53
[syzbot] Monthly block report (Mar 2026) 0 (1) 2026/03/03 23:41
[syzbot] [block?] WARNING in wbt_init_enable_default 2 (4) 2026/02/13 03:30

Sample crash report:
0x000000000001-0x000000020000 : ""
ftl_cs: FTL header corrupt!
"mq-deadline" elevator initialization, failed -12, falling back to "none"
------------[ cut here ]------------
!rwb
WARNING: block/blk-wbt.c:784 at wbt_init_enable_default+0xcb/0x120 block/blk-wbt.c:784, CPU#0: syz.0.23/6066
Modules linked in:
CPU: 0 UID: 0 PID: 6066 Comm: syz.0.23 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:wbt_init_enable_default+0xcb/0x120 block/blk-wbt.c:784
Code: df e8 d9 cc a2 06 4c 89 e7 e8 e1 38 00 00 48 89 df e8 29 56 a2 06 e8 04 76 2b fd 5b 5d 41 5c e9 9b 22 a4 06 e8 f6 75 2b fd 90 <0f> 0b 90 eb 81 e8 eb 75 2b fd 90 0f 0b 90 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc90003b3f590 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88803364e000 RCX: 0000000000000040
RDX: ffff88802e719e40 RSI: ffffffff84daf70a RDI: ffffffff8bfa9120
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff82708ed4 R12: ffff88802b37a620
R13: ffff88803364e390 R14: ffff88802b37a630 R15: ffff88803364e090
FS:  00007f472043f6c0(0000) GS:ffff8881245a5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000da000 CR3: 000000007affe000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 blk_register_queue+0x39e/0x4e0 block/blk-sysfs.c:942
 __add_disk+0x73f/0xe40 block/genhd.c:528
 add_disk_fwnode+0x118/0x5c0 block/genhd.c:597
 add_mtd_blktrans_dev+0xd0b/0x1520 drivers/mtd/mtd_blkdevs.c:382
 mtdblock_add_mtd+0x1cc/0x270 drivers/mtd/mtdblock.c:333
 blktrans_notify_add drivers/mtd/mtd_blkdevs.c:464 [inline]
 blktrans_notify_add+0xa2/0xf0 drivers/mtd/mtd_blkdevs.c:456
 add_mtd_device+0xbe3/0x1750 drivers/mtd/mtdcore.c:820
 mtd_add_partition+0x30a/0x660 drivers/mtd/mtdpart.c:279
 mtdchar_blkpg_ioctl+0x207/0x250 drivers/mtd/mtdchar.c:562
 mtdchar_ioctl+0x1670/0x1fd0 drivers/mtd/mtdchar.c:1218
 mtdchar_unlocked_ioctl+0xb0/0xf0 drivers/mtd/mtdchar.c:1241
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f471f59bf79
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:00007f472043f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f471f816090 RCX: 00007f471f59bf79
RDX: 0000000000000000 RSI: 0000000000001269 RDI: 0000000000000004
RBP: 00007f471f6327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f471f816128 R14: 00007f471f816090 R15: 00007ffe9ebc84a8
 </TASK>

Crashes (410):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/12 20:41 upstream 37a93dd5c49b 504cb1bf .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/02/08 16:53 upstream e7aa57247700 4c131dc4 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/02/07 12:50 upstream 2687c848e578 f20fc9f9 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in wbt_init_enable_default
2025/12/29 08:40 upstream c875a6c32467 d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in wbt_init_enable_default
2025/12/23 12:45 upstream b927546677c8 d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in wbt_init_enable_default
2026/04/05 01:21 upstream 3aae9383f42f 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/04/04 19:09 upstream 7ca6d1cfec80 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in wbt_init_enable_default
2026/04/04 05:50 upstream 631919fb12fe 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in wbt_init_enable_default
2026/04/04 00:38 upstream 631919fb12fe 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/04/03 21:48 upstream 631919fb12fe 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in wbt_init_enable_default
2026/04/02 20:46 upstream 5619b098e2fb 8b15d4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in wbt_init_enable_default
2026/04/02 16:09 upstream 9147566d8016 8b15d4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in wbt_init_enable_default
2026/04/02 13:17 upstream 9147566d8016 0cb124d5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in wbt_init_enable_default
2026/04/02 09:31 upstream 9147566d8016 91bc79b0 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/04/02 06:36 upstream 9147566d8016 0cb124d5 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/03/31 05:21 upstream d0c3bcd5b897 d0af506e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/03/30 04:56 upstream f242ac4a0944 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/03/28 13:21 upstream 7df48e363130 ef441708 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/03/28 10:48 upstream 7df48e363130 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in wbt_init_enable_default
2026/03/27 19:11 upstream 46b513250491 74a13a23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/03/27 12:17 upstream 46b513250491 50cdcaa1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in wbt_init_enable_default
2026/03/27 07:36 upstream 46b513250491 50cdcaa1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in wbt_init_enable_default
2026/03/27 06:16 upstream 46b513250491 50cdcaa1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/03/26 20:11 upstream 0138af2472df 4b3d9a38 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/03/26 16:38 upstream 0138af2472df fca8d360 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in wbt_init_enable_default
2026/03/26 08:52 upstream d2a43e7f89da c6143aac .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/03/25 06:55 upstream bbeb83d3182a 35e4ff71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/03/24 22:09 upstream e3c33bc767b5 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in wbt_init_enable_default
2026/03/24 15:09 upstream c369299895a5 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/03/24 08:18 upstream c369299895a5 baf8bf12 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/03/24 02:02 upstream c369299895a5 baf8bf12 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in wbt_init_enable_default
2026/03/23 16:22 upstream c369299895a5 5e3db351 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in wbt_init_enable_default
2026/03/23 14:22 upstream c369299895a5 5e3db351 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in wbt_init_enable_default
2026/03/23 12:47 upstream c369299895a5 5e3db351 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in wbt_init_enable_default
2026/03/22 11:54 upstream 113ae7b4decc 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in wbt_init_enable_default
2026/03/22 03:09 upstream 113ae7b4decc 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in wbt_init_enable_default
2026/03/20 23:15 upstream 0e4f8f1a3d08 85bf2a64 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in wbt_init_enable_default
2026/03/20 17:13 upstream 0e4f8f1a3d08 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in wbt_init_enable_default
2026/04/02 17:17 upstream 9147566d8016 8b15d4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in wbt_init_enable_default
2025/12/24 07:28 upstream b927546677c8 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in wbt_init_enable_default
2025/12/25 04:03 upstream ccd1cdca5cd4 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in wbt_init_enable_default
2026/04/05 04:08 net 1caa871bb061 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in wbt_init_enable_default
2026/04/03 19:03 net 51f4e090b9f8 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in wbt_init_enable_default
2026/04/01 01:01 net 47ab2c12c87a aeea1c72 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in wbt_init_enable_default
2026/03/31 16:30 bpf c369299895a5 aeea1c72 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in wbt_init_enable_default
2026/03/27 15:27 bpf c369299895a5 74a13a23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in wbt_init_enable_default
2026/03/26 23:54 bpf c369299895a5 fca8d360 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in wbt_init_enable_default
2026/03/22 23:59 bpf ec69c9e88315 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in wbt_init_enable_default
2026/03/21 06:49 net e069034bd660 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in wbt_init_enable_default
2026/04/06 11:47 bpf-next a1aa9ef47c29 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in wbt_init_enable_default
2026/04/05 17:35 bpf-next 6a14beefab45 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in wbt_init_enable_default
2026/04/05 16:16 net-next 3741f8fa004b 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in wbt_init_enable_default
2026/04/04 04:06 bpf-next 6a14beefab45 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in wbt_init_enable_default
2026/04/01 03:24 bpf-next 0eeb0094ba03 fb8b2c26 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in wbt_init_enable_default
2026/03/30 12:19 net-next cf0d9080c6f7 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in wbt_init_enable_default
2026/03/28 19:02 net-next ced629dc8e5c 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in wbt_init_enable_default
2026/03/28 16:33 bpf-next 5e961eebef30 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in wbt_init_enable_default
2026/03/28 02:00 bpf-next 5e961eebef30 74a13a23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in wbt_init_enable_default
2026/03/26 03:49 net-next d1e59a469737 c6143aac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in wbt_init_enable_default
2026/03/23 09:52 net-next fb78a629b4f0 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in wbt_init_enable_default
2026/03/23 03:59 bpf-next bfec8e88ff60 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in wbt_init_enable_default
2026/03/22 09:06 net-next fb78a629b4f0 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in wbt_init_enable_default
2026/03/21 13:10 bpf-next 4b21ea502483 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in wbt_init_enable_default
2026/04/05 19:43 linux-next cc13002a9f98 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in wbt_init_enable_default
2026/04/02 03:40 linux-next bd0f139e5fc1 0cb124d5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in wbt_init_enable_default
2026/03/30 23:47 linux-next cf7c3c02fdd0 458630d8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in wbt_init_enable_default
2026/03/25 23:18 linux-next 66ba480978ce 4367a094 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in wbt_init_enable_default
2026/03/22 22:23 linux-next 785f0eb2f85d 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in wbt_init_enable_default
2026/03/21 15:32 linux-next 785f0eb2f85d 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in wbt_init_enable_default
* Struck through repros no longer work on HEAD.