From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v4 binutils] Add BPF support to binutils...
Date: Fri, 05 May 2017 15:43:04 -0400 (EDT)
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From: David Miller <davem@davemloft.net>
Date: Mon, 01 May 2017 23:51:58 -0400 (EDT)

> From: Alexei Starovoitov <ast@fb.com>
> Date: Mon, 1 May 2017 20:49:21 -0700
> 
>> (gdb) x/10i bpf_prog1
>>    0x0 <bpf_prog1>:	ldimm64	r0, 590618314553
>>    0x10 <bpf_prog1+16>:	stdw	[r1+-8], r10
>>    0x18 <bpf_prog1+24>:	lddw	r10, [r1+-8]
>>    0x20 <bpf_prog1+32>:	add	r0, -1879113726
>>    0x28 <bpf_prog1+40>:	lddw	r1, [r0+0]
>>    0x30 <bpf_prog1+48>:	exit
>>    0x38:	Cannot access memory at address 0x38
>> 
>> the last line also seems wrong. Off by 1 error?
> 
> Maybe, I'll look into it tomorrow.

This is not a BPF specific problem, GDB does this for any non-linked
object you try to inspect under it.  F.e. on a sparc object:

(gdb) x/10i 0
   0x0 <foo>:   retl
   0x4 <foo+4>: clr  %o0
   0x8: Cannot access memory at address 0x8
(gdb)

Same behavior.