More concise disassembly of https://gist.github.com/nickdesaulniers/395129e75d9f7afe028db832145594d8

__jump_table.txt

; $ objdump -d -r -j __jump_table arch/x86/kernel/cpu/mtrr/generic.o

arch/x86/kernel/cpu/mtrr/generic.o:     file format elf64-x86-64


Disassembly of section __jump_table:

0000000000000000 <__jump_table>:
	...
  			10: R_X86_64_PC32	.text+0x3f9
			14: R_X86_64_PC32	.text+0x400
			18: R_X86_64_PC64	__tracepoint_read_msr+0x8
			20: R_X86_64_PC32	.text+0x434
			24: R_X86_64_PC32	.text+0x400
			28: R_X86_64_PC64	__tracepoint_read_msr+0x8
      ...

generic.o.s

; $ gdb -batch -ex "file arch/x86/kernel/cpu/mtrr/generic.o" -ex "disassemble get_fixed_ranges"
Dump of assembler code for function get_fixed_ranges:
...
   0x00000000000003f9 <+89>:	nopl   0x0(%rax,%rax,1)
   0x00000000000003fe <+94>:	jmp    0x40f <get_fixed_ranges+111>
   0x0000000000000400 <+96>:	mov    $0x258,%edi
   0x0000000000000405 <+101>:	mov    %rbx,%rsi
   0x0000000000000408 <+104>:	xor    %edx,%edx
   0x000000000000040a <+106>:	callq  0x40f <get_fixed_ranges+111>
   0x000000000000040f <+111>:	mov    %r14d,0x0(%rip)        # 0x416 <get_fixed_ranges+118>
   0x0000000000000416 <+118>:	shr    $0x20,%rbx
   0x000000000000041a <+122>:	mov    %ebx,0x0(%rip)        # 0x420 <get_fixed_ranges+128>
   0x0000000000000420 <+128>:	mov    $0x259,%ecx
   0x0000000000000425 <+133>:	rdmsr  
   0x0000000000000427 <+135>:	mov    %rax,%r14
   0x000000000000042a <+138>:	mov    %rdx,%rbx
   0x000000000000042d <+141>:	shl    $0x20,%rbx
   0x0000000000000431 <+145>:	or     %rax,%rbx
   0x0000000000000434 <+148>:	nopl   0x0(%rax,%rax,1)
   0x0000000000000439 <+153>:	jmp    0x44a <get_fixed_ranges+170>
   0x000000000000043b <+155>:	mov    $0x259,%edi
   0x0000000000000440 <+160>:	mov    %rbx,%rsi
   0x0000000000000443 <+163>:	xor    %edx,%edx
   0x0000000000000445 <+165>:	callq  0x44a <get_fixed_ranges+170>
   0x000000000000044a <+170>:	mov    %r14d,0x0(%rip)        # 0x451 <get_fixed_ranges+177>
...

warning.sh

$ make CC=clang
...
arch/x86/kernel/cpu/mtrr/generic.o: warning: objtool: get_fixed_ranges()+0x9b: unreachable instruction
$ python -c 'print(hex(0x3a0 + 0x9b))'
0x43b