Greeting, FYI, we noticed the following commit (built with gcc-9): commit: 6509ca051abf4ff60d63732badcb2173a715f741 ("drm/dp: Add drm_dp_downstream_{min,max}_tmds_clock()") https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master in testcase: boot on test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 8G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +-------------------------------------------------------+------------+------------+ | | fe7cf496e5 | 6509ca051a | +-------------------------------------------------------+------------+------------+ | boot_successes | 4 | 0 | | boot_failures | 0 | 7 | | PANIC:double_fault | 0 | 7 | | double_fault:#[##] | 0 | 7 | | EIP:handle_exception | 0 | 7 | | Kernel_panic-not_syncing:Fatal_exception_in_interrupt | 0 | 7 | +-------------------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot [ 15.006925] Applicom driver: $Id: ac.c,v 1.30 2000/03/22 16:03:57 dwmw2 Exp $ [ 15.007450] ac.o: No PCI boards found. [ 15.007720] ac.o: For an ISA board you must supply memory and irq parameters. [ 15.008278] toshiba: not a supported Toshiba laptop [ 15.010558] random: get_random_u32 called from arch_rnd+0x1c/0x40 with crng_init=0 [ 15.011048] traps: PANIC: double fault, error_code: 0x0 [ 15.011048] double fault: 0000 [#1] PREEMPT SMP PTI [ 15.011048] CPU: 1 PID: 147 Comm: modprobe Not tainted 5.9.0-rc4-00881-g6509ca051abf4 #1 [ 15.011048] EIP: handle_exception+0x0/0x128 [ 15.011048] Code: 24 10 36 89 48 fc 8b 4c 24 0c 81 e1 ff ff 00 00 36 89 48 f8 8b 4c 24 08 36 89 48 f4 8b 4c 24 04 36 89 48 f0 59 8d 60 f0 58 cf 0f a0 50 b8 d8 00 00 00 8e e0 58 81 64 24 10 ff ff 00 00 f7 44 [ 15.011048] EAX: 2262d000 EBX: ffa2efbc ECX: 00000000 EDX: c28dacf6 [ 15.011048] ESI: e2629ff0 EDI: ffa2f000 EBP: 00000000 ESP: ffa2e008 [ 15.011048] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010006 [ 15.011048] CR0: 80050033 CR2: ffa2dffc CR3: 02db2000 CR4: 000406b0 [ 15.011048] Call Trace: [ 15.011048] [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80/0x80 [ 15.011048] ? sysvec_kvm_asyncpf_interrupt+0x50/0x50 [ 15.011048] ? restore_all_switch_stack+0x80 [ 15.011048] Lost 217 message(s)! [ 15.011048] ---[ end trace 94527bd98e02a7a3 ]--- [ 15.011048] EIP: handle_exception+0x0/0x128 [ 15.011048] Code: 24 10 36 89 48 fc 8b 4c 24 0c 81 e1 ff ff 00 00 36 89 48 f8 8b 4c 24 08 36 89 48 f4 8b 4c 24 04 36 89 48 f0 59 8d 60 f0 58 cf 0f a0 50 b8 d8 00 00 00 8e e0 58 81 64 24 10 ff ff 00 00 f7 44 [ 15.011048] EAX: 2262d000 EBX: ffa2efbc ECX: 00000000 EDX: c28dacf6 [ 15.011048] ESI: e2629ff0 EDI: ffa2f000 EBP: 00000000 ESP: ffa2e008 [ 15.011048] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010006 [ 15.011048] CR0: 80050033 CR2: ffa2dffc CR3: 02db2000 CR4: 000406b0 [ 15.011048] Kernel panic - not syncing: Fatal exception in interrupt [ 15.011048] Kernel Offset: disabled Kboot worker: lkp-worker30 Elapsed time: 60 To reproduce: # build kernel cd linux cp config-5.9.0-rc4-00881-g6509ca051abf4 .config make HOSTCC=gcc-9 CC=gcc-9 ARCH=i386 olddefconfig prepare modules_prepare bzImage git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k job-script # job-script is attached in this email Thanks, lkp