Greeting, FYI, we noticed the following commit (built with clang-14): commit: e757c47436b07a6e8f1dcb19523abb9db24a1c7b ("fs/namei: shut up clang Wbitwise-instead-of-logical warning") https://git.kernel.org/cgit/linux/kernel/git/arnd/playground.git randconfig-5.16-next in testcase: trinity version: trinity-i386-4d2343bd-1_20200320 with following parameters: number: 99999 group: group-01 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 16G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +----------------------------------------------------------------------------+------------+------------+ | | 673b15fc61 | e757c47436 | +----------------------------------------------------------------------------+------------+------------+ | Kernel_panic-not_syncing:VFS:Unable_to_mount_root_fs_on_unknown-block(#,#) | 0 | 34 | +----------------------------------------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot <oliver.sang(a)intel.com&gt; [ 52.770369][ T1] VFS: Cannot open root device "ram0" or unknown-block(0,0): error -2 [ 52.772390][ T1] Please append a correct "root=" boot option; here are the available partitions: [ 52.774686][ T1] 1f00 131072 mtdblock0 [ 52.774723][ T1] (driver?) [ 52.776609][ T1] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) [ 52.778725][ T1] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc5-next-20211013-00155-ge757c47436b0 #1 9f8c15cc907121e8e7226b18a2350e0b59810df9 [ 52.781718][ T1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 52.783860][ T1] Call Trace: [ 52.784680][ T1] <TASK> [ 52.785381][ T1] dump_stack_lvl+0xa5/0xce [ 52.786453][ T1] dump_stack+0x11/0x12 [ 52.787486][ T1] panic+0x231/0x6ee [ 52.788405][ T1] mount_block_root+0x296/0x2e5 [ 52.789596][ T1] mount_root+0xbb/0xf4 [ 52.790576][ T1] prepare_namespace+0x27f/0x2ba [ 52.791738][ T1] kernel_init_freeable+0x1a9/0x1b5 [ 52.793033][ T1] ? rest_init+0x310/0x310 [ 52.794109][ T1] kernel_init+0x1c/0x300 [ 52.795205][ T1] ? rest_init+0x310/0x310 [ 52.796212][ T1] ret_from_fork+0x22/0x30 [ 52.797335][ T1] </TASK> [ 52.798392][ T1] Kernel Offset: disabled To reproduce: # build kernel cd linux cp config-5.15.0-rc5-next-20211013-00155-ge757c47436b0 .config make HOSTCC=clang-14 CC=clang-14 ARCH=x86_64 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 # if come across any failure that blocks the test, # please remove ~/.lkp and /lkp dir to run from a clean state. --- 0DAY/LKP+ Test Infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/lkp@lists.01.org Intel Corporation Thanks, Oliver Sang