[peterz-queue:sched/proxy] [sched/fair] 3272406483: RIP:set_next_task_idle

From: kernel test robot

Date: Tue May 26 2026 - 23:00:05 EST

Hello,

kernel test robot noticed "RIP:set_next_task_idle" on:

commit: 327240648305b45989b073e5e241e3aebd039570 ("sched/fair: Add newidle balance to pick_task_fair()")
https://git.kernel.org/cgit/linux/kernel/git/peterz/queue.git sched/proxy

in testcase: stress-ng
version: stress-ng-x86_64-c09248db3-1_20260512
with following parameters:

nr_threads: 100%
testtime: 60s
test: prctl
cpufreq_governor: performance

config: x86_64-rhel-9.4
compiler: gcc-14
test machine: 256 threads 2 sockets Intel(R) Xeon(R) 6767P CPU @ 2.4GHz (Granite Rapids) with 256G memory

(please refer to attached dmesg/kmsg for entire log/backtrace)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-lkp/202605271046.4dc3cd8c-lkp@xxxxxxxxx

[ 247.632336][ T9849] ------------[ cut here ]------------
[ 247.634037][ T0] ------------[ cut here ]------------
[ 247.634058][T10006] ------------[ cut here ]------------
[ 247.634062][T10006] WARNING: kernel/sched/sched.h:1788 at set_next_task_idle+0xce/0x130, CPU#216: stress-ng-prctl/10006
[ 247.634068][T10006] Modules linked in: ipmi_ssif intel_ifs i10nm_edac skx_edac_common nfit x86_pkg_temp_thermal coretemp btrfs libblake2b intel_uncore_frequency_tpmi kvm_intel raid6_pq cxl_pci intel_rapl_tpmi intel_tpmi_power_domains isst_tpmi xor isst_tpmi_core intel_rapl_common intel_uncore_frequency_common cxl_mem snd_pcm kvm cxl_acpi snd_timer binfmt_misc cxl_port ast irqbypass pmt_telemetry iaa_crypto cxl_pmem snd dax_hmem nvme isst_if_mmio drm_client_lib intel_cstate qat_4xxx pmt_discovery pmt_class intel_sdsi intel_vsec_tpmi drm_shmem_helper acpi_ipmi soundcore cxl_core idxd i2c_i801 intel_qat intel_uncore pcspkr ipmi_si einj nvme_core isst_if_common intel_vsec i2c_smbus idxd_bus drm_kms_helper wmi crc8 ipmi_devintf libnvdimm ipmi_msghandler pfr_update joydev pfr_telemetry fuse drm nfnetlink
[ 247.634098][T10006] CPU: 216 UID: 0 PID: 10006 Comm: stress-ng-prctl Not tainted 7.1.0-rc2+ #1 PREEMPTLAZY
[ 247.634100][T10006] Hardware name: IEIT SYSTEMS NF5180-M8-A0-R0-00/NF5180-M8-A0-R0-00, BIOS 02.03.00 03/03/2025
[ 247.634102][T10006] RIP: 0010:set_next_task_idle (sched/sched.h:1788 (discriminator 1) sched/sched.h:1802 (discriminator 1) sched/pelt.h:80 (discriminator 1) sched/pelt.h:157 (discriminator 1) sched/idle.c:498 (discriminator 1))
[ 247.634104][T10006] Code: 0b 00 00 5b 5d c3 cc cc cc cc 83 83 f8 0d 00 00 01 83 bb 60 0b 00 00 01 0f 87 68 ff ff ff 0f 0b e9 61 ff ff ff 83 f9 01 77 a6 <0f> 0b 0f 0b eb a0 0f 0b 48 8b 83 58 0b 00 00 48 01 d0 48 2b 83 48
All code
========
0: 0b 00 or (%rax),%eax
2: 00 5b 5d add %bl,0x5d(%rbx)
5: c3 ret
6: cc int3
7: cc int3
8: cc int3
9: cc int3
a: 83 83 f8 0d 00 00 01 addl $0x1,0xdf8(%rbx)
11: 83 bb 60 0b 00 00 01 cmpl $0x1,0xb60(%rbx)
18: 0f 87 68 ff ff ff ja 0xffffffffffffff86
1e: 0f 0b ud2
20: e9 61 ff ff ff jmp 0xffffffffffffff86
25: 83 f9 01 cmp $0x1,%ecx
28: 77 a6 ja 0xffffffffffffffd0
2a:* 0f 0b ud2 <-- trapping instruction
2c: 0f 0b ud2
2e: eb a0 jmp 0xffffffffffffffd0
30: 0f 0b ud2
32: 48 8b 83 58 0b 00 00 mov 0xb58(%rbx),%rax
39: 48 01 d0 add %rdx,%rax
3c: 48 rex.W
3d: 2b .byte 0x2b
3e: 83 .byte 0x83
3f: 48 rex.W

Code starting with the faulting instruction
===========================================
0: 0f 0b ud2
2: 0f 0b ud2
4: eb a0 jmp 0xffffffffffffffa6
6: 0f 0b ud2
8: 48 8b 83 58 0b 00 00 mov 0xb58(%rbx),%rax
f: 48 01 d0 add %rdx,%rax
12: 48 rex.W
13: 2b .byte 0x2b
14: 83 .byte 0x83
15: 48 rex.W
[ 247.634106][T10006] RSP: 0018:ffa0000032147b70 EFLAGS: 00010097
[ 247.634107][T10006] RAX: 000000000175bccb RBX: ff11062cb6c31d00 RCX: 0000000000000000
[ 247.634108][T10006] RDX: 00000039a6323750 RSI: ff11060e88082100 RDI: ff11062cb6c31d00
[ 247.634109][T10006] RBP: ff11060e88082100 R08: ffffffff813c52d0 R09: ff11060e97964200
[ 247.634110][T10006] R10: 000000000000006c R11: 000000000000001a R12: ffffffff83f09d00
[ 247.634111][T10006] R13: ff11062cb6c31d00 R14: ff11060e88082100 R15: ff11062cb6c31d00
[ 247.634112][T10006] FS: 0000000000000000(0000) GS:ff11062d32d28000(0000) knlGS:0000000000000000
[ 247.634113][T10006] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 247.634114][T10006] CR2: 000055f864cf9c90 CR3: 0000062d81422001 CR4: 0000000000f73ef0
[ 247.634114][T10006] PKRU: 55555554
[ 247.634115][T10006] Call Trace:
[ 247.634118][T10006] <TASK>
[ 247.634120][T10006] pick_next_task (sched/sched.h:2737 sched/core.c:6346)
[ 247.634123][T10006] __schedule (sched/core.c:7120)
[ 247.634126][T10006] do_task_dead (sched/core.c:7223)
[ 247.634128][T10006] do_exit (trace/events/sched.h:335 (discriminator 4) trace/events/sched.h:335 (discriminator 4) exit.c:975 (discriminator 4))
[ 247.634131][T10006] do_group_exit (exit.c:1128)
[ 247.634133][T10006] __x64_sys_exit_group (exit.c:1157)
[ 247.634135][T10006] x64_sys_call (x86/entry/syscall_64.c:37)
[ 247.634136][T10006] do_syscall_64 (x86/entry/syscall_64.c:63 (discriminator 1) x86/entry/syscall_64.c:94 (discriminator 1))
[ 247.634138][T10006] ? __x64_sys_rt_sigaction (signal.c:4646 signal.c:4630 signal.c:4630)
[ 247.634140][T10006] ? do_syscall_64 (x86/include/asm/atomic64_64.h:15 linux/atomic/atomic-arch-fallback.h:2583 linux/atomic/atomic-long.h:38 linux/atomic/atomic-instrumented.h:3189 linux/unwind_deferred.h:37 linux/irq-entry-common.h:278 linux/entry-common.h:320 x86/entry/syscall_64.c:100)
[ 247.634142][T10006] ? restore_altstack (signal.c:4469)
[ 247.634143][T10006] ? __do_sys_rt_sigreturn (x86/kernel/signal_64.c:268 (discriminator 1))
[ 247.634146][T10006] ? do_syscall_64 (x86/include/asm/atomic64_64.h:15 linux/atomic/atomic-arch-fallback.h:2583 linux/atomic/atomic-long.h:38 linux/atomic/atomic-instrumented.h:3189 linux/unwind_deferred.h:37 linux/irq-entry-common.h:278 linux/entry-common.h:320 x86/entry/syscall_64.c:100)
[ 247.634147][T10006] ? __perf_sw_event (events/internal.h:229 events/core.c:11020 events/core.c:11045)
[ 247.634149][T10006] ? handle_mm_fault (linux/perf_event.h:1604 memory.c:6617 memory.c:6744)
[ 247.634151][T10006] ? syscall_user_dispatch (entry/syscall_user_dispatch.c:51 (discriminator 2))
[ 247.634152][ T0] ------------[ cut here ]------------
[ 247.634152][T10006] ? do_user_addr_fault (x86/mm/fault.c:1335)
[ 247.634155][T10006] ? do_syscall_64 (x86/include/asm/preempt.h:95 linux/randomize_kstack.h:58 x86/entry/syscall_64.c:92)
[ 247.634157][T10006] ? irqentry_exit (x86/include/asm/atomic64_64.h:15 linux/atomic/atomic-arch-fallback.h:2583 linux/atomic/atomic-long.h:38 linux/atomic/atomic-instrumented.h:3189 linux/unwind_deferred.h:37 linux/irq-entry-common.h:278 linux/irq-entry-common.h:325 entry/common.c:162)
[ 247.634155][ T0] WARNING: kernel/sched/fair.c:7617 at hrtick_start_fair+0x88/0xb0, CPU#67: swapper/67/0
[ 247.634160][T10006] entry_SYSCALL_64_after_hwframe (x86/entry/entry_64.S:130)
[ 247.634161][ T0] Modules linked in: ipmi_ssif intel_ifs i10nm_edac
[ 247.634163][T10006] RIP: 0033:0x7fd729a742d5
[ 247.634165][ T0] skx_edac_common
[ 247.634166][ T0] nfit
[ 247.634168][T10006] Code: Unable to access opcode bytes at 0x7fd729a742ab.

Code starting with the faulting instruction
===========================================
[ 247.634170][ T0] x86_pkg_temp_thermal
[ 247.634171][T10006] RSP: 002b:00007fff9cf52e58 EFLAGS: 00000202
[ 247.634173][ T0] coretemp
[ 247.634172][ T0] ------------[ cut here ]------------
[ 247.634173][T10006] ORIG_RAX: 00000000000000e7
[ 247.634175][ T0] btrfs libblake2b
[ 247.634177][T10006] RAX: ffffffffffffffda RBX: 00007fd7290a35c8 RCX: 00007fd729a742d5
[ 247.634179][ T0] intel_uncore_frequency_tpmi
[ 247.634180][T10006] RDX: 00000000000000e7 RSI: fffffffffffffc20 RDI: 0000000000000000
[ 247.634177][ T0] WARNING: kernel/sched/fair.c:6316 at set_next_entity+0x1cc/0x270, CPU#71: swapper/71/0
[ 247.634182][ T0] kvm_intel
[ 247.634183][T10006] RBP: 0000000000002716 R08: 00000000ffffffff R09: 0000000000000178
[ 247.634185][ T0] Modules linked in:
[ 247.634185][T10006] R10: 0000000000000019 R11: 0000000000000202 R12: 00007fff9cf52e64
[ 247.634185][ T0] raid6_pq
[ 247.634188][ T0] ipmi_ssif
[ 247.634189][T10006] R13: 00007fd6ff030000 R14: 000055f86505e0e0 R15: 00000000000026b5
[ 247.634190][ T0] cxl_pci
[ 247.634192][ T0] intel_ifs
[ 247.634193][T10006] </TASK>
[ 247.634194][ T0] intel_rapl_tpmi
[ 247.634195][ T0] i10nm_edac
[ 247.634196][T10006] ---[ end trace 0000000000000000 ]---
[ 247.634197][ T0] intel_tpmi_power_domains
[ 247.634198][ T0] skx_edac_common
[ 247.634200][ T0] isst_tpmi

The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20260527/202605271046.4dc3cd8c-lkp@xxxxxxxxx

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki