Greeting, FYI, we noticed the following commit (built with gcc-11): commit: 710f5f9f706e680f2bc99cdbcd301a29ee784a7c ("tty: serial: handle HAS_IOPORT dependencies") https://git.kernel.org/cgit/linux/kernel/git/niks/linux.git has_ioport_v3 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): +---------------------------------------------+------------+------------+ | | 41e9474656 | 710f5f9f70 | +---------------------------------------------+------------+------------+ | boot_successes | 40 | 0 | | boot_failures | 0 | 40 | | BUG:kernel_NULL_pointer_dereference,address | 0 | 40 | | Oops:#[##] | 0 | 40 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 40 | +---------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot [ 1.732701][ T0] printk: console [tty0] enabled [ 1.734232][ T0] BUG: kernel NULL pointer dereference, address: 00000000 [ 1.736384][ T0] #PF: supervisor instruction fetch in kernel mode [ 1.738336][ T0] #PF: error_code(0x0010) - not-present page [ 1.740141][ T0] *pdpt = 0000000000000000 *pde = f000ff53f000ff53 [ 1.741937][ T0] Oops: 0010 [#1] SMP PTI [ 1.743123][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.18.0-rc4-00034-g710f5f9f706e #1 [ 1.745451][ T0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 1.747901][ T0] EIP: 0x0 [ 1.748934][ T0] Code: Unable to access opcode bytes at RIP 0xffffffd6. [ 1.751013][ T0] EAX: d932b940 EBX: d932b940 ECX: 00000000 EDX: 00000001 [ 1.753142][ T0] ESI: 00000000 EDI: d8cedea4 EBP: d8cede8c ESP: d8cede60 [ 1.755240][ T0] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00210046 [ 1.757298][ T0] CR0: 80050033 CR2: ffffffd6 CR3: 191f8000 CR4: 000006b0 [ 1.759093][ T0] Call Trace: [ 1.760063][ T0] serial8250_do_set_termios+0x248/0x4c0 [ 1.761761][ T0] ? serial8250_do_set_termios+0x4c0/0x4c0 [ 1.763541][ T0] serial8250_set_termios+0x25/0x40 [ 1.765104][ T0] uart_set_options+0xc4/0x140 [ 1.766508][ T0] serial8250_console_setup+0x82/0x180 [ 1.768162][ T0] univ8250_console_setup+0x3d/0x80 [ 1.769712][ T0] try_enable_preferred_console+0x95/0x140 [ 1.771496][ T0] register_console+0x5d/0x240 [ 1.773067][ T0] ? serial8250_isa_init_ports+0x170/0x170 [ 1.774765][ T0] register_console+0x4d/0x80 [ 1.776204][ T0] univ8250_console_init+0x20/0x2a [ 1.777786][ T0] console_init+0xa8/0xdb [ 1.779153][ T0] start_kernel+0x30f/0x46d [ 1.780564][ T0] i386_start_kernel+0x48/0x4a [ 1.782074][ T0] startup_32_smp+0x161/0x164 [ 1.783613][ T0] Modules linked in: [ 1.784727][ T0] CR2: 0000000000000000 [ 1.786035][ T0] ---[ end trace 0000000000000000 ]--- [ 1.787589][ T0] EIP: 0x0 [ 1.788542][ T0] Code: Unable to access opcode bytes at RIP 0xffffffd6. [ 1.790689][ T0] EAX: d932b940 EBX: d932b940 ECX: 00000000 EDX: 00000001 [ 1.792752][ T0] ESI: 00000000 EDI: d8cedea4 EBP: d8cede8c ESP: d8cede60 [ 1.794740][ T0] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00210046 [ 1.796913][ T0] CR0: 80050033 CR2: ffffffd6 CR3: 191f8000 CR4: 000006b0 [ 1.798987][ T0] Kernel panic - not syncing: Fatal exception To reproduce: # build kernel cd linux cp config-5.18.0-rc4-00034-g710f5f9f706e .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