Re: [RFC PATCH v4 01/28] sched: Cache aware load-balancing

From: kernel test robot
Date: Mon Aug 11 2025 - 21:31:11 EST



Hello,

kernel test robot noticed "Oops:general_protection_fault,probably_for_non-canonical_address#:#[##]SMP_KASAN" on:

commit: 2ae6ef14daceb295598846a328dd65fde6b16c99 ("[RFC PATCH v4 01/28] sched: Cache aware load-balancing")
url: https://github.com/intel-lab-lkp/linux/commits/Chen-Yu/sched-Cache-aware-load-balancing/20250809-131716
base: v6.16
patch link: https://lore.kernel.org/all/9157186cf9e3fd541f62c637579ff736b3704c51.1754712565.git.tim.c.chen@xxxxxxxxxxxxxxx/
patch subject: [RFC PATCH v4 01/28] sched: Cache aware load-balancing

in testcase: boot

config: x86_64-randconfig-103-20250810
compiler: gcc-12
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

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


+----------------------------------------------------------------------------------+-------+------------+
| | v6.16 | 2ae6ef14da |
+----------------------------------------------------------------------------------+-------+------------+
| Oops:general_protection_fault,probably_for_non-canonical_address#:#[##]SMP_KASAN | 0 | 5 |
| KASAN:null-ptr-deref_in_range[#-#] | 0 | 5 |
| RIP:_find_next_bit | 0 | 5 |
| Kernel_panic-not_syncing:Fatal_exception | 0 | 5 |
+----------------------------------------------------------------------------------+-------+------------+


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/202508111054.58c525c-lkp@xxxxxxxxx


[ 18.108061][ T1] usbcore: registered new interface driver i2c-diolan-u2c
[ 18.111512][ T36] input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input0
[ 18.113593][ T1] Driver for 1-wire Dallas network protocol.
[ 18.119966][ T1] f71882fg: Not a Fintek device
[ 18.120517][ T1] f71882fg: Not a Fintek device
[ 18.142462][ T63] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000012: 0000 [#1] SMP KASAN
[ 18.144289][ T63] KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097]
[ 18.145594][ T63] CPU: 0 UID: 0 PID: 63 Comm: modprobe Not tainted 6.16.0-00001-g2ae6ef14dace #1 PREEMPT(none)
[ 18.146207][ T63] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
[ 18.146207][ T63] RIP: 0010:_find_next_bit (kbuild/src/consumer/lib/find_bit.c:156 (discriminator 2))
[ 18.146207][ T63] Code: 48 89 d3 48 83 c8 ff 83 e2 3f 49 89 fe 48 c1 eb 06 c4 62 e9 f7 e8 b8 ff ff 37 00 4c 8d 3c df 48 c1 e0 2a 4c 89 fa 48 c1 ea 03 <80> 3c 02 00 74 08 4c 89 ff e8 cc 76 52 ff 49 8b 07 4c 21 e8 49 bd
All code
========
0: 48 89 d3 mov %rdx,%rbx
3: 48 83 c8 ff or $0xffffffffffffffff,%rax
7: 83 e2 3f and $0x3f,%edx
a: 49 89 fe mov %rdi,%r14
d: 48 c1 eb 06 shr $0x6,%rbx
11: c4 62 e9 f7 e8 shlx %rdx,%rax,%r13
16: b8 ff ff 37 00 mov $0x37ffff,%eax
1b: 4c 8d 3c df lea (%rdi,%rbx,8),%r15
1f: 48 c1 e0 2a shl $0x2a,%rax
23: 4c 89 fa mov %r15,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
2a:* 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2e: 74 08 je 0x38
30: 4c 89 ff mov %r15,%rdi
33: e8 cc 76 52 ff call 0xffffffffff527704
38: 49 8b 07 mov (%r15),%rax
3b: 4c 21 e8 and %r13,%rax
3e: 49 rex.WB
3f: bd .byte 0xbd

Code starting with the faulting instruction
===========================================
0: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
4: 74 08 je 0xe
6: 4c 89 ff mov %r15,%rdi
9: e8 cc 76 52 ff call 0xffffffffff5276da
e: 49 8b 07 mov (%r15),%rax
11: 4c 21 e8 and %r13,%rax
14: 49 rex.WB
15: bd .byte 0xbd
[ 18.146207][ T63] RSP: 0000:ffffc900001f7d28 EFLAGS: 00010206
[ 18.146207][ T63] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: fffffbfff0bdd81a
[ 18.146207][ T63] RDX: 0000000000000012 RSI: 0000000000000002 RDI: 0000000000000090
[ 18.146207][ T63] RBP: ffffc900001f7d50 R08: 0000000000000000 R09: 0000000000000003
[ 18.146207][ T63] R10: ffffffff8145362f R11: ffffed103099ffd5 R12: 0000000000000002
[ 18.146207][ T63] R13: ffffffffffffffff R14: 0000000000000090 R15: 0000000000000090
[ 18.146207][ T63] FS: 0000000000000000(0000) GS:ffff888428798000(0000) knlGS:0000000000000000
[ 18.146207][ T63] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
[ 18.146207][ T63] CR2: 00000000f7fc18c8 CR3: 0000000185368000 CR4: 00000000000406b0
[ 18.146207][ T63] Call Trace:
[ 18.146207][ T63] <TASK>
[ 18.146207][ T63] task_cache_work (kbuild/src/consumer/include/linux/find.h:71 (discriminator 2) kbuild/src/consumer/kernel/sched/fair.c:1325 (discriminator 2))
[ 18.146207][ T63] ? _raw_spin_unlock_irq (kbuild/src/consumer/arch/x86/include/asm/paravirt.h:671 kbuild/src/consumer/include/linux/spinlock_api_smp.h:159 kbuild/src/consumer/kernel/locking/spinlock.c:202)
[ 18.146207][ T63] ? __pfx_task_cache_work (kbuild/src/consumer/kernel/sched/fair.c:1299)
[ 18.146207][ T63] ? __this_cpu_preempt_check (kbuild/src/consumer/lib/smp_processor_id.c:67)


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20250811/202508111054.58c525c-lkp@xxxxxxxxx



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