hi, Paul, we actually want to consult you about this patch. by it, the config has below diff with parent in this tests (we use randconfig here) --- /pkg/linux/i386-randconfig-004-20240810/gcc-12/157f4b896656dfe6ad6d37c94ca9a885d52f35ab/.config 2024-08-12 04:00:50.715727095 +0800 +++ /pkg/linux/i386-randconfig-004-20240810/gcc-12/a7adbae9c55d7f85b3b8c0e8e9417e5d52793137/.config 2024-08-12 04:02:38.647990561 +0800 @@ -136,7 +136,7 @@ CONFIG_BSD_PROCESS_ACCT_V3=y CONFIG_TREE_RCU=y CONFIG_PREEMPT_RCU=y CONFIG_RCU_EXPERT=y -CONFIG_TREE_SRCU=y +CONFIG_TINY_SRCU=y CONFIG_TASKS_RCU_GENERIC=y CONFIG_FORCE_TASKS_RCU=y CONFIG_NEED_TASKS_RCU=y then we saw issue show for this commit: 157f4b896656dfe6 a7adbae9c55d7f85b3b8c0e8e94 ---------------- --------------------------- fail:runs %reproduction fail:runs | | | :6 67% 6:6 rcutorture.busted_srcud.fail :6 83% 6:6 dmesg.EIP:rcu_torture_stats_print :6 83% 6:6 dmesg.WARNING:at_kernel/rcu/rcutorture.c:#rcu_torture_stats_print[rcutorture] another diff is, for parent, we can see: [ 465.948962] busted_srcud-torture:--- End of test: SUCCESS: nreaders=1 nfakewriters=4 stat_interval=60 verbose=1 test_no_idle_hz=1 shuffle_interval=3 stutter=5 irqreader=1 fqs_duration=0 fqs_holdoff=0 fqs_stutter=3 test_boost=1/0 test_boost_interval=7 test_boost_duration=4 shutdown_secs=0 stall_cpu=0 stall_cpu_holdoff=10 stall_cpu_irqsoff=0 stall_cpu_block=0 stall_cpu_repeat=0 n_barrier_cbs=0 onoff_interval=0 onoff_holdoff=0 read_exit_delay=13 read_exit_burst=16 nocbs_nthreads=0 nocbs_toggle=1000 test_nmis=0 but for this commit: [ 417.566774] busted_srcud-torture:--- End of test: FAILURE: nreaders=1 nfakewriters=4 stat_interval=60 verbose=1 test_no_idle_hz=1 shuffle_interval=3 stutter=5 irqreader=1 fqs_duration=0 fqs_holdoff=0 fqs_stutter=3 test_boost=1/0 test_boost_interval=7 test_boost_duration=4 shutdown_secs=0 stall_cpu=0 stall_cpu_holdoff=10 stall_cpu_irqsoff=0 stall_cpu_block=0 stall_cpu_repeat=0 n_barrier_cbs=0 onoff_interval=0 onoff_holdoff=0 read_exit_delay=13 read_exit_burst=16 nocbs_nthreads=0 nocbs_toggle=1000 test_nmis=0 are these expected? below full report FYI. Hello, kernel test robot noticed "WARNING:at_kernel/rcu/rcutorture.c:#rcu_torture_stats_print[rcutorture]" on: commit: a7adbae9c55d7f85b3b8c0e8e9417e5d52793137 ("srcu: Enable Tiny SRCU On all CONFIG_SMP=n kernels") https://github.com/paulmckrcu/linux dev.2024.08.05a in testcase: rcutorture version: with following parameters: runtime: 300s test: default torture_type: busted_srcud compiler: gcc-12 test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -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 <oliver.sang@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-lkp/202408191537.5ab14400-lkp@xxxxxxxxx [ 180.101544][ T569] busted_srcud-torture: !!! [ 180.101750][ T569] ------------[ cut here ]------------ [ 180.103079][ T569] WARNING: CPU: 0 PID: 569 at kernel/rcu/rcutorture.c:2263 rcu_torture_stats_print+0x361/0x5a2 [rcutorture] [ 180.104531][ T569] Modules linked in: rcutorture torture intel_rapl_msr ipmi_devintf ipmi_msghandler mousedev bochs drm_vram_helper intel_rapl_common drm_ttm_helper crc32_pclmul ttm aesni_intel crypto_simd serio_raw drm_kms_helper rapl fuse drm drm_panel_orientation_quirks backlight i2c_core [ 180.108333][ T569] CPU: 0 UID: 0 PID: 569 Comm: rcu_torture_sta Tainted: G T 6.11.0-rc1-00103-ga7adbae9c55d #1 89f8a658c4adbda3212056ebb1acba93a3453734 [ 180.110128][ T569] Tainted: [T]=RANDSTRUCT [ 180.110676][ T569] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 [ 180.111951][ T569] EIP: rcu_torture_stats_print+0x361/0x5a2 [rcutorture] [ 180.112889][ T569] Code: 74 02 0f 0b 6a 00 31 c9 b8 98 4d 54 ef 0f b6 db e8 9d 96 c1 c1 31 c9 89 da b8 80 4d 54 ef 6a 00 e8 8d 96 c1 c1 4e 58 5a 7e 02 <0f> 0b 6a 00 b8 68 4d 54 ef 31 c9 89 da e8 76 96 c1 c1 58 68 8d 96 [ 180.115329][ T569] EAX: 00000000 EBX: 00000001 ECX: 00000000 EDX: 00000000 [ 180.116208][ T569] ESI: 00000002 EDI: 00000000 EBP: b6be3f64 ESP: b6be3ee8 [ 180.116977][ T569] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 EFLAGS: 00010202 [ 180.117817][ T569] CR0: 80050033 CR2: 08082db0 CR3: 069fb000 CR4: 00040690 [ 180.118722][ T569] Call Trace: [ 180.119180][ T569] ? show_regs+0x65/0x71 [ 180.119838][ T569] ? rcu_torture_stats_print+0x361/0x5a2 [rcutorture c084aa8ea4885af620a5fd08bf5503a17a237677] [ 180.121034][ T569] ? __warn+0x92/0xd3 [ 180.121591][ T569] ? report_bug+0xdd/0x156 [ 180.122212][ T569] ? rcu_torture_stats_print+0x361/0x5a2 [rcutorture c084aa8ea4885af620a5fd08bf5503a17a237677] [ 180.123567][ T569] ? exc_overflow+0x3d/0x3d [ 180.124162][ T569] ? handle_bug+0x2b/0x4b [ 180.124693][ T569] ? exc_invalid_op+0x24/0x61 [ 180.125262][ T569] ? handle_exception+0x164/0x164 [ 180.125896][ T569] ? exc_overflow+0x3d/0x3d [ 180.126448][ T569] ? rcu_torture_stats_print+0x361/0x5a2 [rcutorture c084aa8ea4885af620a5fd08bf5503a17a237677] [ 180.127705][ T569] ? exc_overflow+0x3d/0x3d [ 180.128320][ T569] ? rcu_torture_stats_print+0x361/0x5a2 [rcutorture c084aa8ea4885af620a5fd08bf5503a17a237677] [ 180.129584][ T569] rcu_torture_stats+0x3f/0x60 [rcutorture c084aa8ea4885af620a5fd08bf5503a17a237677] [ 180.130712][ T569] kthread+0x109/0x10e [ 180.131226][ T569] ? rcu_torture_stats_print+0x5a2/0x5a2 [rcutorture c084aa8ea4885af620a5fd08bf5503a17a237677] [ 180.136140][ T569] ? list_del_init+0x25/0x25 [ 180.136464][ T569] ret_from_fork+0x34/0x4d [ 180.136776][ T569] ? list_del_init+0x25/0x25 [ 180.137093][ T569] ret_from_fork_asm+0x12/0x20 [ 180.137422][ T569] entry_INT80_32+0x124/0x124 [ 180.137758][ T569] irq event stamp: 1025 [ 180.138078][ T569] hardirqs last enabled at (1047): [<b10bdcb0>] console_unlock+0x9b/0xfd [ 180.138658][ T569] hardirqs last disabled at (1056): [<b10bdc97>] console_unlock+0x82/0xfd [ 180.139225][ T569] softirqs last enabled at (1042): [<b106fcea>] handle_softirqs+0x28a/0x2f3 [ 180.139838][ T569] softirqs last disabled at (1033): [<b1b627cf>] __do_softirq+0xf/0x13 [ 180.140398][ T569] ---[ end trace 0000000000000000 ]--- The kernel config and materials to reproduce are available at: https://download.01.org/0day-ci/archive/20240819/202408191537.5ab14400-lkp@xxxxxxxxx -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki