FYI, we noticed the following commit (built with gcc-7): commit: 02519fa3c43164aa8ee0ebbe1b464a568130a36f ("function_graph: Use a ftrace_graph_ret_stub() for return") https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master in testcase: trinity with following parameters: runtime: 300s test-description: Trinity is a linux system call fuzz tester. test-url: http://codemonkey.org.uk/projects/trinity/ on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 2G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +-----------------------------------------------------------------------------------------------+------------+------------+ | | 52fde6e70c | 02519fa3c4 | +-----------------------------------------------------------------------------------------------+------------+------------+ | boot_successes | 4 | 0 | | boot_failures | 0 | 4 | | BUG:kernel_reboot-without-warning_in_early-boot_stage,last_printk:early_console_in_setup_code | 0 | 4 | +-----------------------------------------------------------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot <lkp(a)intel.com&gt; early console in setup code BUG: kernel reboot-without-warning in early-boot stage, last printk: early console in setup code Linux version 5.1.0-rc3-00023-g02519fa #1 Command line: ip=::::vm-snb-quantal-ia32-804::dhcp root=/dev/ram0 user=lkp job=/lkp/jobs/scheduled/vm-snb-quantal-ia32-804/trinity-300s-quantal-core-i386-2019-04-26.cgz-02519fa3c43-20190429-62375-116iczn-1.yaml ARCH=x86_64 kconfig=x86_64-randconfig-s3-04261012 branch=linux-devel/devel-hourly-2019042607 commit=02519fa3c43164aa8ee0ebbe1b464a568130a36f BOOT_IMAGE=/pkg/linux/x86_64-randconfig-s3-04261012/gcc-7/02519fa3c43164aa8ee0ebbe1b464a568130a36f/vmlinuz-5.1.0-rc3-00023-g02519fa max_uptime=1500 RESULT_ROOT=/result/trinity/300s/vm-snb-quantal-ia32/quantal-core-i386-2019-04-26.cgz/x86_64-randconfig-s3-04261012/gcc-7/02519fa3c43164aa8ee0ebbe1b464a568130a36f/3 LKP_SERVER=inn debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 net.ifnames=0 printk.devkmsg=on panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 drbd.minor_count=8 systemd.log_level=err ignore_loglevel console=tty0 earlyprintk=ttyS0,115200 console=ttyS0,115200 vga=normal rw rcuperf.shutdown=0 Elapsed time: 30 To reproduce: # build kernel cd linux cp config-5.1.0-rc3-00023-g02519fa .config make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 olddefconfig make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 prepare make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 modules_prepare make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 SHELL=/bin/bash make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 bzImage git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email Thanks, lkp