linux boot (grub)

Arguments passed to grub at boottime (either from grub.conf or commandline ) are stored in /proc/cmdline

for example:
cat /proc/cmdline
ro root=/dev/mapper/vg_centos-lv_root rd_LVM_LV=vg_centos/lv_root rd_LVM_LV=vg_centos/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=129M@0M rhgb quiet