From: kernel test robot <yi1.lai@intel.com>
To: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: oe-lkp@lists.linux.dev, lkp@intel.com,
K Prateek Nayak <kprateek.nayak@amd.com>,
linux-kernel@vger.kernel.org, aubrey.li@linux.intel.com,
yu.c.chen@intel.com, Peter Zijlstra <peterz@infradead.org>,
Tim Chen <tim.c.chen@linux.intel.com>,
Ingo Molnar <mingo@redhat.com>,
Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Andrew Morton <akpm@linux-foundation.org>,
Arnd Bergmann <arnd@arndb.de>,
linux-arch@vger.kernel.org, linux-s390@vger.kernel.org,
linuxppc-dev@lists.ozlabs.org, linux-mips@vger.kernel.org,
loongarch@lists.linux.dev, driver-core@lists.linux.dev,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
Valentin Schneider <vschneid@redhat.com>,
Shrikanth Hegde <sshegde@linux.ibm.com>,
yi1.lai@intel.com
Subject: Re: [RFC PATCH v3 13/13] sched/fair: Switch nohz.idle_cpus to use sbm
Date: Mon, 19 Oct 2026 09:06:23 +0800 [thread overview]
Message-ID: <202610190859.d3459a50-lkp@intel.com> (raw)
In-Reply-To: <20261001192849.74788-14-kprateek.nayak@amd.com>
Hello,
kernel test robot noticed "kernel_BUG_at_kernel/smpboot.c" on:
commit: d7dd59cf6a0f621f224947f960403a747b0836f0 ("[RFC PATCH v3 13/13] sched/fair: Switch nohz.idle_cpus to use sbm")
url: https://github.com/intel-lab-lkp/linux/commits/K-Prateek-Nayak/lib-sbm-Introduce-helpers-for-architectures-to-configure-LLC-properties/20261001-192837
patch link: https://lore.kernel.org/all/20261001192849.74788-14-kprateek.nayak@amd.com/
patch subject: [RFC PATCH v3 13/13] sched/fair: Switch nohz.idle_cpus to use sbm
in testcase: boot
config: i386-randconfig-1006-20261010
compiler: clang-22
test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 4 -m 4G
(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 <yi1.lai@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202610190859.d3459a50-lkp@intel.com
[ 2.426107][ T37] ------------[ cut here ]------------
[ 2.430168][ T37] kernel BUG at kernel/smpboot.c:133!
[ 2.433726][ T37] Oops: invalid opcode: 0000 [#1] SMP PTI
[ 2.436546][ T37] CPU: 3 UID: 0 PID: 37 Comm: ksoftirqd/3 Tainted: G T 7.3.0-rc1+ #1 PREEMPTLAZY
[ 2.436546][ T37] Tainted: [T]=RANDSTRUCT
[ 2.436546][ T37] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 2.436546][ T37] EIP: smpboot_thread_fn (smpboot.c:117)
[ 2.436546][ T37] Code: 83 7e 04 00 74 13 8b 06 31 d2 0f a3 05 6c 07 59 84 0f 92 c2 e8 12 65 b7 01 89 f0 e8 4b e9 2e 00 31 c0 83 c4 08 5e 5f 5b 5d c3 <0f> 0b b8 08 52 f5 83 e8 75 85 e6 ff 0f 0b b8 f8 51 f5 83 e8 69 85
All code
========
0: 83 7e 04 00 cmpl $0x0,0x4(%rsi)
4: 74 13 je 0x19
6: 8b 06 mov (%rsi),%eax
8: 31 d2 xor %edx,%edx
a: 0f a3 05 6c 07 59 84 bt %eax,-0x7ba6f894(%rip) # 0xffffffff8459077d
11: 0f 92 c2 setb %dl
14: e8 12 65 b7 01 call 0x1b7652b
19: 89 f0 mov %esi,%eax
1b: e8 4b e9 2e 00 call 0x2ee96b
20: 31 c0 xor %eax,%eax
22: 83 c4 08 add $0x8,%esp
25: 5e pop %rsi
26: 5f pop %rdi
27: 5b pop %rbx
28: 5d pop %rbp
29: c3 ret
2a:* 0f 0b ud2 <-- trapping instruction
2c: b8 08 52 f5 83 mov $0x83f55208,%eax
31: e8 75 85 e6 ff call 0xffffffffffe685ab
36: 0f 0b ud2
38: b8 f8 51 f5 83 mov $0x83f551f8,%eax
3d: e8 .byte 0xe8
3e: 69 .byte 0x69
3f: 85 .byte 0x85
Code starting with the faulting instruction ===========================================
0: 0f 0b ud2
2: b8 08 52 f5 83 mov $0x83f55208,%eax
7: e8 75 85 e6 ff call 0xffffffffffe68581
c: 0f 0b ud2
e: b8 f8 51 f5 83 mov $0x83f551f8,%eax
13: e8 .byte 0xe8
14: 69 .byte 0x69
15: 85 .byte 0x85
[ 2.436546][ T37] EAX: 00000003 EBX: 858ac510 ECX: 83e26f98 EDX: 83c50f80
[ 2.436546][ T37] ESI: 8500dfb0 EDI: 00000000 EBP: 858e1f68 ESP: 858e1f54
[ 2.436546][ T37] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010293
[ 2.436546][ T37] CR0: 80050033 CR2: 00000000 CR3: 047ae000 CR4: 000006b0
[ 2.436546][ T37] Call Trace:
[ 2.436546][ T37] kthread (kthread.c:436)
[ 2.436546][ T37] ? smpboot_unregister_percpu_thread (linux/list.h:261)
[ 2.436546][ T37] ? __do_trace_sched_kthread_stop_ret (trace/events/sched.h:38 (discriminator 13))
[ 2.436546][ T37] ret_from_fork (x86/kernel/process.c:158)
[ 2.436546][ T37] ? __do_trace_sched_kthread_stop_ret (trace/events/sched.h:38 (discriminator 13))
[ 2.436546][ T37] ret_from_fork_asm (x86/entry/entry_32.S:736)
[ 2.436546][ T37] entry_INT80_32 (x86/entry/entry_32.S:940)
[ 2.436546][ T37] Modules linked in:
[ 2.493945][ T37] ---[ end trace 0000000000000000 ]---
[ 2.496265][ T37] EIP: smpboot_thread_fn (smpboot.c:117)
[ 2.498528][ T37] Code: 83 7e 04 00 74 13 8b 06 31 d2 0f a3 05 6c 07 59 84 0f 92 c2 e8 12 65 b7 01 89 f0 e8 4b e9 2e 00 31 c0 83 c4 08 5e 5f 5b 5d c3 <0f> 0b b8 08 52 f5 83 e8 75 85 e6 ff 0f 0b b8 f8 51 f5 83 e8 69 85
All code
========
0: 83 7e 04 00 cmpl $0x0,0x4(%rsi)
4: 74 13 je 0x19
6: 8b 06 mov (%rsi),%eax
8: 31 d2 xor %edx,%edx
a: 0f a3 05 6c 07 59 84 bt %eax,-0x7ba6f894(%rip) # 0xffffffff8459077d
11: 0f 92 c2 setb %dl
14: e8 12 65 b7 01 call 0x1b7652b
19: 89 f0 mov %esi,%eax
1b: e8 4b e9 2e 00 call 0x2ee96b
20: 31 c0 xor %eax,%eax
22: 83 c4 08 add $0x8,%esp
25: 5e pop %rsi
26: 5f pop %rdi
27: 5b pop %rbx
28: 5d pop %rbp
29: c3 ret
2a:* 0f 0b ud2 <-- trapping instruction
2c: b8 08 52 f5 83 mov $0x83f55208,%eax
31: e8 75 85 e6 ff call 0xffffffffffe685ab
36: 0f 0b ud2
38: b8 f8 51 f5 83 mov $0x83f551f8,%eax
3d: e8 .byte 0xe8
3e: 69 .byte 0x69
3f: 85 .byte 0x85
Code starting with the faulting instruction ===========================================
0: 0f 0b ud2
2: b8 08 52 f5 83 mov $0x83f55208,%eax
7: e8 75 85 e6 ff call 0xffffffffffe68581
c: 0f 0b ud2
e: b8 f8 51 f5 83 mov $0x83f551f8,%eax
13: e8 .byte 0xe8
14: 69 .byte 0x69
15: 85 .byte 0x85
The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20261019/202610190859.d3459a50-lkp@intel.com
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
next prev parent reply other threads:[~2026-10-19 1:06 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-01 19:28 [RFC PATCH v3 00/13] lib, sched: Introduce sparsebitmap (sbm) K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 01/13] lib/sbm: Introduce helpers for architectures to configure LLC properties K Prateek Nayak
2026-10-07 5:43 ` Shrikanth Hegde
2026-10-12 2:11 ` K Prateek Nayak
2026-10-12 22:22 ` Tim Chen
2026-10-01 19:28 ` [RFC PATCH v3 02/13] drivers/base/arch_topology: Add support for initializing sbm topology K Prateek Nayak
2026-10-12 23:41 ` Tim Chen
2026-10-01 19:28 ` [RFC PATCH v3 03/13] LoongArch: Initialize CPU _PXM relation for disabled CPUs from SRAT K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 04/13] LoongArch: Configure sbm topology during SMP preparation K Prateek Nayak
2026-10-07 3:51 ` [RFC PATCH v3.1 " K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 05/13] MIPS: Initialize sbm topology on multi-node systems K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 06/13] powerpc/setup: Initialize sbm topology based on coregroup / NUMA topology K Prateek Nayak
2026-10-07 14:43 ` Shrikanth Hegde
2026-10-12 2:29 ` K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 07/13] s390/topology: Initialize sbm topology during topology_init_early() K Prateek Nayak
2026-10-07 10:19 ` Mete Durlu
2026-10-12 2:20 ` K Prateek Nayak
2026-10-13 10:14 ` Mete Durlu
2026-10-01 19:28 ` [RFC PATCH v3 08/13] sparc64: Initialize sbm topology on multi-LLC system K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 09/13] x86/cpu/topology: Initialize sbm topology after topology parsing K Prateek Nayak
2026-10-03 8:27 ` Chen Yu
2026-10-04 6:17 ` K Prateek Nayak
2026-10-07 3:52 ` [RFC PATCH v3.1 " K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 10/13] lib/sbm: Dynamically allocate sbm index when CPU is activated K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 11/13] lib/sbm: Add helpers to allocate, set, clear, and traverse the bits on sbm K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 12/13] sched/fair: Allocate nohz.idle_cpus_mask during sched_init_smp() K Prateek Nayak
2026-10-01 19:28 ` [RFC PATCH v3 13/13] sched/fair: Switch nohz.idle_cpus to use sbm K Prateek Nayak
2026-10-19 1:06 ` kernel test robot [this message]
2026-10-03 9:10 ` [RFC PATCH v3 00/13] lib, sched: Introduce sparsebitmap (sbm) Chen Yu
2026-10-04 6:13 ` K Prateek Nayak
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