BUG: scheduling while atomic in kernfs_drain

Status: premoderation: reported on 2026/08/01 01:34
Reported-by: syzbot+69c853ee63005ce8447d@syzkaller.appspotmail.com
First crash: 56d, last: 8d07h

Sample crash report:
BUG: scheduling while atomic: syz.0.93/615/0x00000002
Modules linked in:
CPU: 0 UID: 0 PID: 615 Comm: syz.0.93 Not tainted syzkaller #0 59fd58dbf897e2c8ba33f91efbb53ce34092dff9
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 __schedule_bug+0x12b/0x200 kernel/sched/core.c:6629
 schedule_debug kernel/sched/core.c:6656 [inline]
 __schedule+0xb85/0x20b0 kernel/sched/core.c:7700
 __schedule_loop kernel/sched/core.c:7960 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7975
 kernfs_drain+0x278/0x420 fs/kernfs/dir.c:507
 __kernfs_remove+0x402/0x940 fs/kernfs/dir.c:1524
 kernfs_remove_by_name_ns+0x100/0x180 fs/kernfs/dir.c:1742
 sysfs_remove_file_ns+0x68/0x80 fs/sysfs/file.c:506
 sysfs_remove_file include/linux/sysfs.h:773 [inline]
 device_remove_file drivers/base/core.c:3074 [inline]
 device_del+0x56c/0xcf0 drivers/base/core.c:3879
 device_unregister drivers/base/core.c:3922 [inline]
 device_destroy+0xb0/0x100 drivers/base/core.c:4521
 android_device_destroy+0x118/0x180 drivers/usb/gadget/android_configfs_uevent.c:223
 gadgets_drop+0x1d/0x30 drivers/usb/gadget/configfs.c:2075
 client_drop_item fs/configfs/dir.c:943 [inline]
 configfs_rmdir+0x8ba/0x9b0 fs/configfs/dir.c:1546
 vfs_rmdir+0x3db/0x560 fs/namei.c:4348
 do_rmdir+0x29a/0x590 fs/namei.c:4407
 __do_sys_rmdir fs/namei.c:4426 [inline]
 __se_sys_rmdir fs/namei.c:4424 [inline]
 __x64_sys_rmdir+0x4b/0x60 fs/namei.c:4424
 x64_sys_call+0xaf7/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:85
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f631059e159
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:00007f6311533028 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 00007f6310825fa0 RCX: 00007f631059e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000002c0
RBP: 00007f631063506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6310826038 R14: 00007f6310825fa0 R15: 00007ffe67aa1d28
 </TASK>
------------[ cut here ]------------
WARNING: CPU: 0 PID: 615 at lib/stackdepot.c:635 stack_depot_save_flags+0x266/0x800 lib/stackdepot.c:633
Modules linked in:
CPU: 0 UID: 0 PID: 615 Comm: syz.0.93 Tainted: G        W          syzkaller #0 59fd58dbf897e2c8ba33f91efbb53ce34092dff9
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:stack_depot_save_flags+0x266/0x800 lib/stackdepot.c:635
Code: 48 83 3d 34 fe db 05 00 0f 84 00 04 00 00 48 c7 45 c0 00 00 00 00 48 89 d3 65 8b 05 4c 2f 1e 7d 4d 89 d7 a9 00 00 f0 00 74 2d <0f> 0b 48 c7 45 c8 00 00 00 00 9c 8f 45 c8 4c 8b 6d c8 fa 48 c7 c7
RSP: 0018:ffffc9000dac79d0 EFLAGS: 00010206
RAX: 000000007fffffff RBX: ffff8881f54cfa60 RCX: 00000000002cfa60
RDX: ffff8881f54cfa60 RSI: 0000000000000001 RDI: 000000009e20f32f
RBP: ffffc9000dac7a30 R08: 000000002d390eed R09: 000000008925b2b8
R10: 000000000000000d R11: ffffffff8175a7a0 R12: 00000000fd52cfa6
R13: 0000000000000000 R14: ffffc9000dac7a40 R15: 000000000000000d
FS:  00007f63115336c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c355f37 CR3: 000000011f052000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 kasan_save_stack mm/kasan/common.c:50 [inline]
 kasan_save_track+0x4f/0x80 mm/kasan/common.c:70
 kasan_save_free_info+0x44/0x50 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:249 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2445 [inline]
 slab_free mm/slub.c:4714 [inline]
 kfree+0x158/0x440 mm/slub.c:4875
 put_fragment fs/configfs/dir.c:175 [inline]
 release_configfs_dirent fs/configfs/configfs_internal.h:139 [inline]
 configfs_put fs/configfs/configfs_internal.h:157 [inline]
 configfs_d_iput+0x1d8/0x290 fs/configfs/dir.c:63
 dentry_unlink_inode+0x363/0x430 fs/dcache.c:410
 d_delete+0xa8/0x120 fs/dcache.c:2405
 d_delete_notify include/linux/fsnotify.h:358 [inline]
 vfs_rmdir+0x264/0x560 fs/namei.c:4361
 do_rmdir+0x29a/0x590 fs/namei.c:4407
 __do_sys_rmdir fs/namei.c:4426 [inline]
 __se_sys_rmdir fs/namei.c:4424 [inline]
 __x64_sys_rmdir+0x4b/0x60 fs/namei.c:4424
 x64_sys_call+0xaf7/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:85
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f631059e159
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:00007f6311533028 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 00007f6310825fa0 RCX: 00007f631059e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000002c0
RBP: 00007f631063506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6310826038 R14: 00007f6310825fa0 R15: 00007ffe67aa1d28
 </TASK>
---[ end trace 0000000000000000 ]---
BUG: scheduling while atomic: syz.0.93/615/0x00000000
Modules linked in:
CPU: 1 UID: 0 PID: 615 Comm: syz.0.93 Tainted: G        W          syzkaller #0 59fd58dbf897e2c8ba33f91efbb53ce34092dff9
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 __schedule_bug+0x12b/0x200 kernel/sched/core.c:6629
 schedule_debug kernel/sched/core.c:6656 [inline]
 __schedule+0xb85/0x20b0 kernel/sched/core.c:7700
 __schedule_loop kernel/sched/core.c:7960 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7975
 futex_wait_queue+0xfc/0x240 kernel/futex/waitwake.c:376
 __futex_wait+0x15b/0x3d0 kernel/futex/waitwake.c:677
 futex_wait+0x128/0x7c0 kernel/futex/waitwake.c:706
 do_futex+0x32a/0x510 kernel/futex/syscalls.c:132
 __do_sys_futex kernel/futex/syscalls.c:209 [inline]
 __se_sys_futex+0x13c/0x320 kernel/futex/syscalls.c:190
 __x64_sys_futex+0xe9/0x110 kernel/futex/syscalls.c:190
 x64_sys_call+0x227f/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:203
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f631059e159
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:00007f63115330e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f6310825fa8 RCX: 00007f631059e159
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6310825fa8
RBP: 00007f6310825fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6310826038 R14: 00007ffe67aa1c40 R15: 00007ffe67aa1d28
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/17 20:26 android16-6.12 e79b240621d0 8d7d05f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust BUG: scheduling while atomic in kernfs_drain
2026/08/31 11:04 android16-6.12 96b3287eace8 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust BUG: scheduling while atomic in kernfs_drain
2026/08/20 02:26 android16-6.12 d47db5b1e129 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust BUG: scheduling while atomic in kernfs_drain
2026/08/01 01:33 android16-6.12 1a138e24e292 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust BUG: scheduling while atomic in kernfs_drain
* Struck through repros no longer work on HEAD.