WARNING in futex_pivot_pending

Status: upstream: reported C repro on 2026/08/15 14:36
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+9c28ada89c468ad30713@syzkaller.appspotmail.com
First crash: 18d, last: 30m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
268170df assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in futex_pivot_pending 2026/08/12 03:36 2026/08/12 03:36 2026/08/12 04:14 f8d35649
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] futex: Temporarily set the task state to running for pivot pending 1 (1) 2026/08/17 05:33
[syzbot] [kernel?] WARNING in futex_pivot_pending 2 (5) 2026/08/17 05:18
Last patch testing requests (2)
Created Duration User Patch Repo Result
2026/08/17 04:48 23m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci OK job log log
2026/08/16 02:25 22m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci OK job log log

Sample crash report:
------------[ cut here ]------------
do not call blocking ops when !TASK_RUNNING; state=2 set at [<000000005ac9bcea>] prepare_to_wait_event+0x2e4/0x3ac kernel/sched/wait.c:-1
WARNING: kernel/sched/core.c:9124 at __might_sleep+0xc0/0xdc kernel/sched/core.c:9120, CPU#0: syz.0.17/4919
Modules linked in:
CPU: 0 UID: 0 PID: 4919 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026
pstate: 63400005 (nZCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : __might_sleep+0xc0/0xdc kernel/sched/core.c:9120
lr : __might_sleep+0xc0/0xdc kernel/sched/core.c:9120
sp : ffff800094447930
x29: ffff800094447930 x28: ffff8000805a793c x27: ffff800094447a00
x26: 0000000000000000 x25: ffff800094447a08 x24: 0000000000000000
x23: ffff700012888f3c x22: ffff0000d181ee90 x21: 0000000000000002
x20: ffff8000869ca160 x19: 000000000000026f x18: 00000000ffffffff
x17: ffff8000801672c8 x16: ffff80008016750c x15: ffff800080348f2c
x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000002 x9 : 3e2ed006ccb06300
x8 : 3e2ed006ccb06300 x7 : ffff80008048c60c x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff8000802f6830
x2 : 0000000100000000 x1 : ffff0000d181d7c0 x0 : 0000000000000000
Call trace:
 __might_sleep+0xc0/0xdc kernel/sched/core.c:9120 (P)
 __mutex_lock_common kernel/locking/mutex.c:623 [inline]
 __mutex_lock+0xf8/0xf14 kernel/locking/mutex.c:821
 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874
 class_mutex_constructor include/linux/mutex.h:253 [inline]
 futex_pivot_pending+0x30/0xa4 kernel/futex/core.c:1789
 futex_hash_allocate+0x73c/0xc20 kernel/futex/core.c:1872
 futex_hash_prctl+0xd0/0x324 kernel/futex/core.c:2027
 __do_sys_prctl kernel/sys.c:2885 [inline]
 __se_sys_prctl kernel/sys.c:2534 [inline]
 __arm64_sys_prctl+0x8d0/0x13d0 kernel/sys.c:2534
 __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:758
 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590
irq event stamp: 64
hardirqs last  enabled at (63): [<ffff80008048fba4>] vprintk_store+0x924/0xb94 kernel/printk/printk.c:2385
hardirqs last disabled at (64): [<ffff80008690cc28>] el1_brk64+0x20/0x54 arch/arm64/kernel/entry-common.c:445
softirqs last  enabled at (30): [<ffff80008013891c>] local_bh_enable include/linux/bottom_half.h:33 [inline]
softirqs last  enabled at (30): [<ffff80008013891c>] put_cpu_fpsimd_context arch/arm64/kernel/fpsimd.c:251 [inline]
softirqs last  enabled at (30): [<ffff80008013891c>] do_sve_acc+0x32c/0x4b8 arch/arm64/kernel/fpsimd.c:1349
softirqs last disabled at (28): [<ffff8000801386fc>] local_bh_disable include/linux/bottom_half.h:20 [inline]
softirqs last disabled at (28): [<ffff8000801386fc>] get_cpu_fpsimd_context arch/arm64/kernel/fpsimd.c:234 [inline]
softirqs last disabled at (28): [<ffff8000801386fc>] do_sve_acc+0x10c/0x4b8 arch/arm64/kernel/fpsimd.c:1325
---[ end trace 0000000000000000 ]---

Crashes (255):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/27 18:43 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 e2fa417d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/11 16:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f9054278acf4 37a258dd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/11 16:25 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f9054278acf4 37a258dd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/30 11:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/30 00:55 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/29 22:08 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/29 20:55 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/29 19:17 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/29 07:30 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/28 11:20 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/28 09:32 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/27 23:03 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/27 18:19 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/27 14:13 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/27 13:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/27 07:58 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/27 05:37 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/27 00:02 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/26 19:54 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/26 14:28 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/26 09:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/26 06:26 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/26 05:36 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/26 04:27 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/26 00:48 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 19:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 14:02 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 13:10 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 10:44 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 08:37 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 05:46 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 04:34 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 04:33 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/25 01:58 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/24 18:23 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 68f892e99df9 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/24 16:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/24 14:28 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/24 12:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/24 10:53 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/24 06:44 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/24 04:12 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/24 03:50 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/23 21:50 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/23 20:52 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/23 15:07 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/22 21:48 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/22 20:33 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/22 19:07 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/22 16:45 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
2026/08/22 07:45 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in futex_pivot_pending
* Struck through repros no longer work on HEAD.