The x86 bootloader ID specification text uses hexadecimal values without a 0x prefix: D kexec-tools E Extended (see ext_loader_type) F Special (0xFF = undefined) 10 Reserved 11 Minimal Linux Bootloader <http://sebastian-plotz.blogspot.de> 12 OVMF UEFI virtualization stack 13 barebox Which beyond the ambiguity of '13' in isolation, also made me fail a grep -wi '0xd' when I was looking for the kexec bootloader ID definition and caused quite a bit of head-scratching before I found out why it didn't show up. Furthermore, the actual explanatory text uses the 0x prefix: For boot loader IDs above T = 0xD, write T = 0xE to this field and write the extended ID minus 0x10 to the ext_loader_type field. Similarly, the ext_loader_ver field can be used to provide more than four bits for the bootloader version. So make it all both unambiguous, easy to grep and consistent across the entire documentation by prefixing the IDs with 0x. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: linux-kernel@vger.kernel.org