[syzbot] [pm?] WARNING in ct_kernel_exit

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 365f9c7a6b81 Merge branches 'for-next/core' and 'for-next/..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=127b16b9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=72c97575381cec47
dashboard link: https://syzkaller.appspot.com/bug?extid=79883955da3a62652a80
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=124451b9580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=122f9632580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/eafe0adb7386/disk-365f9c7a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/29422d607579/vmlinux-365f9c7a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/98ca955a8b54/Image-365f9c7a.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+798839...@syzkaller.appspotmail.com

vhci_hcd vhci_hcd.1: suspend vhci_hcd
vhci_hcd vhci_hcd.0: suspend vhci_hcd
Disabling non-boot CPUs ...
psci: CPU1 killed (polled 0 ms)
------------[ cut here ]------------
WARNING: kernel/context_tracking.c:120 at ct_kernel_exit+0x1b4/0x1f4 kernel/context_tracking.c:118, CPU#0: syz.1.501/5462
Modules linked in:
CPU: 0 UID: 0 PID: 5462 Comm: syz.1.501 Not tainted syzkaller #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
pstate: 634003c5 (nZCv DAIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : ct_kernel_exit+0x1b4/0x1f4 kernel/context_tracking.c:118
lr : instrument_atomic_read include/linux/instrumented.h:82 [inline]
lr : atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
lr : ct_rcu_watching include/linux/context_tracking_state.h:91 [inline]
lr : ct_kernel_exit+0x13c/0x1f4 kernel/context_tracking.c:119
sp : ffff800095f775f0
x29: ffff800095f775f0 x28: dfff800000000000 x27: ffff800095f77660
x26: 00000000000000c0 x25: ffff700012beeecc x24: ffff800088abf998
x23: ffff800088b0b6a0 x22: ffff0001ade38998 x21: ffff0001ade38998
x20: 0000000000000000 x19: 0000000000000005 x18: 00000000ffffffff
x17: ffff80008a791000 x16: 0000000000000005 x15: ffff80008a31ada0
x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000000
x11: 0000000000000000 x10: ffff600035bc7135 x9 : dfff800000000000
x8 : 0000000000000040 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000008 x3 : ffff8000868e6858
x2 : 0000000000000000 x1 : 0000000000000004 x0 : 0000000000000001
Call trace:
ct_kernel_exit+0x1b4/0x1f4 kernel/context_tracking.c:118 (P)
ct_idle_enter+0x24/0x38 kernel/context_tracking.c:299
ct_cpuidle_enter include/linux/cpuidle.h:134 [inline]
cpu_suspend+0x264/0x474 arch/arm64/kernel/suspend.c:140
psci_system_suspend_enter+0x4c/0x80 drivers/firmware/psci/psci.c:544
suspend_enter kernel/power/suspend.c:468 [inline]
suspend_devices_and_enter+0x88c/0xd0c kernel/power/suspend.c:533
enter_state kernel/power/suspend.c:618 [inline]
pm_suspend+0x498/0x698 kernel/power/suspend.c:644
state_store+0x14c/0x1fc kernel/power/main.c:819
kobj_attr_store+0x6c/0x90 lib/kobject.c:840
sysfs_kf_write+0xe0/0x108 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x260/0x3b8 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x51c/0xa0c fs/read_write.c:687
ksys_write+0x12c/0x228 fs/read_write.c:739
__do_sys_write fs/read_write.c:750 [inline]
__se_sys_write fs/read_write.c:747 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:747
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736
el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
irq event stamp: 69726
hardirqs last enabled at (69725): [<ffff80008690522c>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:187 [inline]
hardirqs last enabled at (69725): [<ffff80008690522c>] _raw_spin_unlock_irq+0x30/0x80 kernel/locking/spinlock.c:206
hardirqs last disabled at (69726): [<ffff800080473cc0>] arch_suspend_disable_irqs+0x34/0x4c kernel/power/suspend.c:403
softirqs last enabled at (68262): [<ffff80008030ff18>] softirq_handle_end kernel/softirq.c:468 [inline]
softirqs last enabled at (68262): [<ffff80008030ff18>] handle_softirqs+0xc28/0xd98 kernel/softirq.c:650
softirqs last disabled at (68257): [<ffff8000800204c0>] __do_softirq+0x14/0x20 kernel/softirq.c:656
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
WARNING: kernel/context_tracking.c:165 at ct_kernel_enter+0x138/0x170 kernel/context_tracking.c:150, CPU#0: syz.1.501/5462
Modules linked in:
CPU: 0 UID: 0 PID: 5462 Comm: syz.1.501 Tainted: G W syzkaller #0 PREEMPT
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
pstate: 600003c5 (nZCv DAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : ct_kernel_enter+0x138/0x170 kernel/context_tracking.c:150
lr : instrument_atomic_read include/linux/instrumented.h:82 [inline]
lr : atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
lr : ct_rcu_watching include/linux/context_tracking_state.h:91 [inline]
lr : ct_kernel_enter+0xc8/0x170 kernel/context_tracking.c:164
sp : ffff800095f775e0
x29: ffff800095f775e0 x28: dfff800000000000 x27: ffff800095f77660
x26: 00000000000000c0 x25: ffff700012beeecc x24: 0000000100000000
x23: ffff800088b0b6a0 x22: ffff800088abf998 x21: ffff0001ade38998
x20: ffff0001ade38998 x19: 0000000000000000 x18: 00000000ffffffff
x17: 000000040044ffff x16: 041000f5b5503510 x15: 0000000000000000
x14: ffff0000db381d40 x13: 0000000000000001 x12: 0000000000000000
x11: 0000000000000000 x10: ffff600035bc7135 x9 : dfff800000000000
x8 : 0000000000000040 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000000 x3 : ffff8000868e6a20
x2 : 0000000000000000 x1 : 0000000000000004 x0 : 0000000000000001
Call trace:
ct_kernel_enter+0x138/0x170 kernel/context_tracking.c:150 (P)
ct_idle_exit+0x24/0x48 kernel/context_tracking.c:317
ct_cpuidle_exit include/linux/cpuidle.h:144 [inline]
cpu_suspend+0x2dc/0x474 arch/arm64/kernel/suspend.c:158
psci_system_suspend_enter+0x4c/0x80 drivers/firmware/psci/psci.c:544
suspend_enter kernel/power/suspend.c:468 [inline]
suspend_devices_and_enter+0x88c/0xd0c kernel/power/suspend.c:533
enter_state kernel/power/suspend.c:618 [inline]
pm_suspend+0x498/0x698 kernel/power/suspend.c:644
state_store+0x14c/0x1fc kernel/power/main.c:819
kobj_attr_store+0x6c/0x90 lib/kobject.c:840
sysfs_kf_write+0xe0/0x108 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x260/0x3b8 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x51c/0xa0c fs/read_write.c:687
ksys_write+0x12c/0x228 fs/read_write.c:739
__do_sys_write fs/read_write.c:750 [inline]
__se_sys_write fs/read_write.c:747 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:747
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736
el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
irq event stamp: 69728
hardirqs last enabled at (69727): [<ffff800084649440>] psci_system_suspend_enter+0x4c/0x80 drivers/firmware/psci/psci.c:544
hardirqs last disabled at (69728): [<ffff800084649440>] psci_system_suspend_enter+0x4c/0x80 drivers/firmware/psci/psci.c:544
softirqs last enabled at (68262): [<ffff80008030ff18>] softirq_handle_end kernel/softirq.c:468 [inline]
softirqs last enabled at (68262): [<ffff80008030ff18>] handle_softirqs+0xc28/0xd98 kernel/softirq.c:650
softirqs last disabled at (68257): [<ffff8000800204c0>] __do_softirq+0x14/0x20 kernel/softirq.c:656
---[ end trace 0000000000000000 ]---
Enabling non-boot CPUs ...
CPU1 is up
OOM killer enabled.
Restarting tasks: Starting
Restarting tasks: Done
random: crng reseeded on system resumption
PM: suspend exit


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