Greeting,

FYI, we noticed the following commit (built with gcc-7):

commit: d0bcc26c0dbe6ac00f0d2ecaaf1312a6de57aaba ("[RFC PATCH 2/2] init: Allow multi-line output of kernel command line")
url: https://github.com/0day-ci/linux/commits/Joe-Perches/printk-init-multi-line-kernel-command-line-logging/20200520-034430


in testcase: boot

on test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):


+-----------------------------------------------------------------------------+------------+------------+
|                                                                             | 33d52c37a7 | d0bcc26c0d |
+-----------------------------------------------------------------------------+------------+------------+
| BUG:kernel_hang_in_early-boot_stage,last_printk:early_console_in_setup_code | 0          | 12         |
+-----------------------------------------------------------------------------+------------+------------+


If you fix the issue, kindly add following tag
Reported-by: kernel test robot <oliver.sang@intel.com>


early console in setup code

<--- kernel actually hang here, below is helper information, please refer to
attached dmesg.xz

BUG: kernel hang in early-boot stage, last printk: early console in setup code
Linux version 5.7.0-rc6-00012-gd0bcc26c0dbe6 #2
Command line: ip=::::vm-snb-i386-8::dhcp root=/dev/ram0 user=lkp job=/lkp/jobs/scheduled/vm-snb-i386-8/boot-1-quantal-i386-core-20190426.cgz-d0bcc26c0dbe6ac00f0d2ecaaf1312a6de57aaba-20200522-12855-1j2fvp6-2.yaml ARCH=i386 kconfig=i386-randconfig-r011-20200520 branch=linux-devel/devel-hourly-2020052109 commit=d0bcc26c0dbe6ac00f0d2ecaaf1312a6de57aaba BOOT_IMAGE=/pkg/linux/i386-randconfig-r011-20200520/gcc-7/d0bcc26c0dbe6ac00f0d2ecaaf1312a6de57aaba/vmlinuz-5.7.0-rc6-00012-gd0bcc26c0dbe6 max_uptime=600 RESULT_ROOT=/result/boot/1/vm-snb-i386/quantal-i386-core-20190426.cgz/i386-randconfig-r011-20200520/gcc-7/d0bcc26c0dbe6ac00f0d2ecaaf1312a6de57aaba/3 LKP_SERVER=inn selinux=0 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 watchdog_thresh=60

Elapsed time: 480


for parent commit, the dmesg will look like below (also attached as dmesg-33d52c37a7.xz)
========================================================================================
early console in setup code
[    0.000000] Linux version 5.7.0-rc6-00011-g33d52c37a7c3e (kbuild@e4179002dd1b) (gcc version 7.5.0 (Ubuntu 7.5.0-6ubuntu2), GNU ld (GNU Binutils for
Debian) 2.34) #1 PREEMPT Fri May 22 11:35:58 CST 2020
[    0.000000] KERNEL supported cpus:
...
[    0.063341] Built 1 zonelists, mobility grouping on.  Total pages: 225452
[    0.063361] Kernel command line: ip=::::vm-snb-i386-29::dhcp root=/dev/ram0 user=lkp job=/lkp/jobs/scheduled/vm-snb-i386-29/boot-1-quantal-i386-core
-20190426.cgz-33d52c37a7c3eb4543234a9dd0faf1c80a462f99-20200522-12645-1yvq3z6-0.yaml ARCH=i386 kconfig=i386-randconfig-r011-20200520 branch=linux-devel
/devel-hourly-2020052109 commit=33d52c37a7c3eb4543234a9dd0faf1c80a462f99 BOOT_IMAGE=/pkg/linux/i386-randconfig-r011-20200520/gcc-7/33d52c37a7c3eb454323
4a9dd0faf1c80a462f99/vmlinuz-5.7.0-rc6-00011-g33d52c37a7c3e max_uptime=600 RESULT_ROOT=/result/boot/1/vm-snb-i386/quantal-i386-core-20190426.cgz/i386-r
andconfig-r011-20200520/gcc-7/33d52c37a7c3eb4543234a9dd0faf1c80a462f99/0 LKP_SERVER=inn selinux=0 debug apic=debug sysrq_always_enabled rcupdate.rcu_cp
u_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.mino
r_count=8 systemd.log_level=err ignore_loglevel console=tty0 earlyprintk=ttyS0,115200 console=ttyS
[    0.064514] sysrq: sysrq always enabled.
========================================================================================


To reproduce:

        # build kernel
	cd linux
	cp config-5.7.0-rc6-00012-gd0bcc26c0dbe6 .config
	make HOSTCC=gcc-7 CC=gcc-7 ARCH=i386 olddefconfig prepare modules_prepare 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,
Oliver Sang