(please be noted we also reported "[net] 3b379e5391: BUG:kernel_NULL_pointer_dereference,address" but this seems a new version and have kind of not small difference, so report again) Greeting, FYI, we noticed the following commit (built with gcc-11): commit: 9b8eb43eca166d72ae89c932548842a4bd7728e2 ("net: set proper memcg for net_init hooks allocations") url: https://github.com/intel-lab-lkp/linux/commits/UPDATE-20220423-234047/Vasily-Averin/net-set-proper-memcg-for-net_init-hooks-allocations/20220423-160759 in testcase: boot on test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 4G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +---------------------------------------------+------------+------------+ | | c00c5e1d15 | 9b8eb43eca | +---------------------------------------------+------------+------------+ | boot_successes | 9 | 0 | | boot_failures | 0 | 24 | | BUG:kernel_NULL_pointer_dereference,address | 0 | 24 | | Oops:#[##] | 0 | 24 | | EIP:__register_pernet_operations | 0 | 24 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 24 | +---------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot [ 0.564344][ T0] BUG: kernel NULL pointer dereference, address: 0000002c [ 0.565241][ T0] #PF: supervisor read access in kernel mode [ 0.565429][ T0] #PF: error_code(0x0000) - not-present page [ 0.565429][ T0] *pdpt = 0000000000000000 *pde = f000ff53f000ff53 [ 0.565429][ T0] Oops: 0000 [#1] SMP PTI [ 0.565429][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.18.0-rc3-00191-g9b8eb43eca16 #1 [ 0.565429][ T0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 0.565429][ T0] EIP: __register_pernet_operations+0x169/0x340 [ 0.565429][ T0] Code: 1e d6 8b 40 08 a8 03 0f 85 44 01 00 00 64 ff 00 64 ff 0d d4 06 1e d6 e9 1d ff ff ff 8d 74 26 00 90 8b 45 e0 89 b8 0c 0f 00 00 < f6> 43 2c 01 0f 85 68 ff ff ff 64 ff 05 d4 06 1e d6 8b 43 08 a8 03 [ 0.565429][ T0] EAX: d5cf4740 EBX: 00000000 ECX: 00000000 EDX: 00000cc0 [ 0.565429][ T0] ESI: d6331340 EDI: 00000000 EBP: d5cedf58 ESP: d5cedf34 [ 0.565429][ T0] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00210246 [ 0.565429][ T0] CR0: 80050033 CR2: 0000002c CR3: 161f8000 CR4: 000406b0 [ 0.565429][ T0] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 0.565429][ T0] DR6: fffe0ff0 DR7: 00000400 [ 0.565429][ T0] Call Trace: [ 0.565429][ T0] ? setup_net+0x44/0x300 [ 0.565429][ T0] register_pernet_operations+0x5c/0xc0 [ 0.565429][ T0] register_pernet_subsys+0x21/0x40 [ 0.565429][ T0] net_ns_init+0xb1/0xf1 [ 0.565429][ T0] start_kernel+0x403/0x46d [ 0.565429][ T0] i386_start_kernel+0x48/0x4a [ 0.565429][ T0] startup_32_smp+0x161/0x164 [ 0.565429][ T0] Modules linked in: [ 0.565429][ T0] CR2: 000000000000002c [ 0.565429][ T0] ---[ end trace 0000000000000000 ]--- [ 0.565429][ T0] EIP: __register_pernet_operations+0x169/0x340 [ 0.565429][ T0] Code: 1e d6 8b 40 08 a8 03 0f 85 44 01 00 00 64 ff 00 64 ff 0d d4 06 1e d6 e9 1d ff ff ff 8d 74 26 00 90 8b 45 e0 89 b8 0c 0f 00 00 43 2c 01 0f 85 68 ff ff ff 64 ff 05 d4 06 1e d6 8b 43 08 a8 03 [ 0.565429][ T0] EAX: d5cf4740 EBX: 00000000 ECX: 00000000 EDX: 00000cc0 [ 0.565429][ T0] ESI: d6331340 EDI: 00000000 EBP: d5cedf58 ESP: d5cedf34 [ 0.565429][ T0] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00210246 [ 0.565429][ T0] CR0: 80050033 CR2: 0000002c CR3: 161f8000 CR4: 000406b0 [ 0.565429][ T0] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 0.565429][ T0] DR6: fffe0ff0 DR7: 00000400 [ 0.565429][ T0] Kernel panic - not syncing: Fatal exception To reproduce: # build kernel cd linux cp config-5.18.0-rc3-00191-g9b8eb43eca16 .config make HOSTCC=gcc-11 CC=gcc-11 ARCH=i386 olddefconfig prepare modules_prepare bzImage modules make HOSTCC=gcc-11 CC=gcc-11 ARCH=i386 INSTALL_MOD_PATH= modules_install cd find lib/ | cpio -o -H newc --quiet | gzip > modules.cgz git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k -m modules.cgz job-script # job-script is attached in this email # if come across any failure that blocks the test, # please remove ~/.lkp and /lkp dir to run from a clean state. -- 0-DAY CI Kernel Test Service https://01.org/lkp