In /usr/bin/kernel-install line 62: if [ "$i" == "--help" -o "$i" == "-h" ]; then ^-- SC2166: Prefer [ p ] || [ q ] as [ p -o q ] is not well defined. In /usr/bin/kernel-install line 69: if [ "$1" == "--verbose" -o "$1" == "-v" ]; then ^-- SC2166: Prefer [ p ] || [ q ] as [ p -o q ] is not well defined. In /usr/bin/kernel-install line 89: read MACHINE_ID < /etc/machine-id ^--^ SC2162: read without -r will mangle backslashes. In /usr/bin/kernel-install line 99: trap "rm -rf '$ENTRY_DIR_ABS'" EXIT INT QUIT PIPE ^------------^ SC2064: Use single quotes, otherwise this expands now rather than when signalled. In /usr/bin/kernel-install line 139: echo "+$f add $KERNEL_VERSION $ENTRY_DIR_ABS $KERNEL_IMAGE ${INITRD_OPTIONS[@]}" ^------------------^ SC2145: Argument mixes string and array. Use * or separate argument. In /usr/bin/kernel-install line 142: if [[ $x == $SKIP_REMAINING ]]; then ^-------------^ SC2053: Quote the right-hand side of == in [[ ]] to prevent glob matching. In /usr/bin/kernel-install line 146: ((ret+=$x)) ^-- SC2004: $/${} is unnecessary on arithmetic variables. In /usr/bin/kernel-install line 166: if [[ $x == $SKIP_REMAINING ]]; then ^-------------^ SC2053: Quote the right-hand side of == in [[ ]] to prevent glob matching. In /usr/bin/kernel-install line 170: ((ret+=$x)) ^-- SC2004: $/${} is unnecessary on arithmetic variables. In /usr/bin/kernel-install line 187: exit $ret ^--^ SC2086: Double quote to prevent globbing and word splitting. Did you mean: exit "$ret" For more information: https://www.shellcheck.net/wiki/SC2145 -- Argument mixes string and array. ... https://www.shellcheck.net/wiki/SC2053 -- Quote the right-hand side of == i... https://www.shellcheck.net/wiki/SC2064 -- Use single quotes, otherwise this...