Re: [Qemu-devel] qemu user x86 working?

[Andi Kleen]

On Sat, Feb 12, 2011 at 10:08:26AM +0200, Blue Swirl wrote:
> On Sat, Feb 12, 2011 at 12:27 AM, Andi Kleen <address@hidden> wrote:
> >
> >> I don't have any problems running a statically linked x86_64
> >> helloworld program in an i386 chroot. Dynamically linked programs try
> >> to use wrong libraries, but at least running
> >> /lib64/ld-linux-x86-64.so.2 directly works.
> >
> > static binary segfaults too. I wonder if it's some setup on my system.
> >
> > I tried disabling the usual suspects like address randomization, but that
> > didn't change things.
> > Or could it be the compiler (gcc 4.5)?
> 
> I don't think so, but that could be ruled out. What happens if you try
> to run some known ld-linux-x86-64.so.2?

It seems to be something with the glibc on the fedora box. If I copy
an static executable from a older suse it works on the fedora system.

I ran into some issues replacing ld-linux though, so I didn't test
the fedora gcc output with a different glibc.

> 
> The last blocks of qemu.log produced by using -d in_asm,out_asm could
> reveal something, please try.

Is that enough?

Don't see anything obvious


0x00000040008117e7:  shr    $0x3,%ecx
0x00000040008117ea:  test   $0x4,%dl
0x00000040008117ed:  mov    %ecx,%ecx
0x00000040008117ef:  rep stos %rax,%es:(%rdi)

OUT: [size=184]
0x602104c0:  mov    0x10(%r14),%rbp
0x602104c4:  mov    %ebp,%ebp
0x602104c6:  xor    %ebx,%ebx
0x602104c8:  mov    %ebx,%ebx
0x602104ca:  mov    %ebp,%ebp
0x602104cc:  shr    $0x3,%rbp
0x602104d0:  mov    %ebp,%ebp
0x602104d2:  mov    0x10(%r14),%r12
0x602104d6:  and    $0x4,%r12d
0x602104da:  mov    %ebp,%ebp
0x602104dc:  mov    %rbp,%r13
0x602104df:  mov    $0x16,%r15d
0x602104e5:  mov    %r15d,0xa0(%r14)
0x602104ec:  mov    %r12,0x98(%r14)
0x602104f3:  mov    %rbx,(%r14)
0x602104f6:  mov    %rbp,0x8(%r14)
0x602104fa:  test   %r13,%r13
0x602104fd:  jne    0x60210528
0x60210503:  jmpq   0x60210508
0x60210508:  mov    $0x40008117f2,%rbp
0x60210512:  mov    %rbp,0x80(%r14)
0x60210519:  mov    $0x7fe2d7c139e1,%rax
0x60210523:  jmpq   0x622324ce
0x60210528:  mov    (%r14),%rbp
0x6021052b:  mov    0x38(%r14),%rbx
0x6021052f:  mov    %rbp,(%rbx)
0x60210532:  movslq 0xa4(%r14),%rbp
0x60210539:  shl    $0x3,%rbp
0x6021053d:  mov    0x38(%r14),%rbx
0x60210541:  add    %rbp,%rbx
0x60210544:  mov    0x8(%r14),%rbp
0x60210548:  dec    %rbp
0x6021054b:  mov    %rbp,0x8(%r14)
0x6021054f:  mov    %rbx,0x38(%r14)
0x60210553:  jmpq   0x60210558
0x60210558:  mov    $0x40008117ef,%rbp
0x60210562:  mov    %rbp,0x80(%r14)
0x60210569:  mov    $0x7fe2d7c139e0,%rax
0x60210573:  jmpq   0x622324ce

----------------
IN: 
0x00000040008117ef:  rep stos %rax,%es:(%rdi)

OUT: [size=130]
0x60210580:  mov    0x8(%r14),%rbp
0x60210584:  test   %rbp,%rbp
0x60210587:  jne    0x602105b2
0x6021058d:  jmpq   0x60210592
0x60210592:  mov    $0x40008117f2,%rbp
0x6021059c:  mov    %rbp,0x80(%r14)
0x602105a3:  mov    $0x7fe2d7c13a59,%rax
0x602105ad:  jmpq   0x622324ce
0x602105b2:  mov    (%r14),%rbp
0x602105b5:  mov    0x38(%r14),%rbx
0x602105b9:  mov    %rbp,(%rbx)
0x602105bc:  movslq 0xa4(%r14),%rbp
0x602105c3:  shl    $0x3,%rbp
0x602105c7:  mov    0x38(%r14),%rbx
0x602105cb:  add    %rbp,%rbx
0x602105ce:  mov    0x8(%r14),%rbp
0x602105d2:  dec    %rbp
0x602105d5:  mov    %rbp,0x8(%r14)
0x602105d9:  mov    %rbx,0x38(%r14)
0x602105dd:  jmpq   0x602105e2
0x602105e2:  mov    $0x40008117ef,%rbp
0x602105ec:  mov    %rbp,0x80(%r14)
0x602105f3:  mov    $0x7fe2d7c13a58,%rax
0x602105fd:  jmpq   0x622324ce

----------------
IN: 
0x00000040008117f2:  jne    0x4000811850

OUT: [size=104]
0x60210610:  mov    0xa0(%r14),%edi
0x60210617:  callq  0x60095060
0x6021061c:  mov    %eax,%ebp
0x6021061e:  shr    $0x6,%rbp
0x60210622:  and    $0x1,%ebp
0x60210625:  test   %rbp,%rbp
0x60210628:  je     0x60210653
0x6021062e:  jmpq   0x60210633
0x60210633:  mov    $0x40008117f4,%rbp
0x6021063d:  mov    %rbp,0x80(%r14)
0x60210644:  mov    $0x7fe2d7c13ad0,%rax
0x6021064e:  jmpq   0x622324ce
0x60210653:  jmpq   0x60210658
0x60210658:  mov    $0x4000811850,%rbp
0x60210662:  mov    %rbp,0x80(%r14)
0x60210669:  mov    $0x7fe2d7c13ad1,%rax
0x60210673:  jmpq   0x622324ce

----------------
IN: 
0x00000040008117f4:  test   $0x2,%dl
0x00000040008117f7:  jne    0x4000811838

OUT: [size=116]
0x60210680:  mov    0x10(%r14),%rbp
0x60210684:  and    $0x2,%ebp
0x60210687:  mov    %rbp,%rbx
0x6021068a:  movzbl %bl,%ebx
0x6021068d:  mov    $0x16,%r12d
0x60210693:  mov    %r12d,0xa0(%r14)
0x6021069a:  mov    %rbp,0x98(%r14)
0x602106a1:  test   %rbx,%rbx
0x602106a4:  jne    0x602106cf
0x602106aa:  jmpq   0x602106af
0x602106af:  mov    $0x40008117f9,%rbp
0x602106b9:  mov    %rbp,0x80(%r14)
0x602106c0:  mov    $0x7fe2d7c13b48,%rax
0x602106ca:  jmpq   0x622324ce
0x602106cf:  jmpq   0x602106d4
0x602106d4:  mov    $0x4000811838,%rbp
0x602106de:  mov    %rbp,0x80(%r14)
0x602106e5:  mov    $0x7fe2d7c13b49,%rax
0x602106ef:  jmpq   0x622324ce

----------------
IN: 
0x00000040008117f9:  and    $0x1,%edx
0x00000040008117fc:  jne    0x4000811830

OUT: [size=122]
0x60210700:  mov    0x10(%r14),%rbp
0x60210704:  and    $0x1,%ebp
0x60210707:  mov    %ebp,%ebx
0x60210709:  mov    %rbp,%r12
0x6021070c:  mov    %r12d,%r12d
0x6021070f:  mov    $0x18,%r13d
0x60210715:  mov    %r13d,0xa0(%r14)
0x6021071c:  mov    %rbp,0x98(%r14)
0x60210723:  mov    %rbx,0x10(%r14)
0x60210727:  test   %r12,%r12
0x6021072a:  jne    0x60210755
0x60210730:  jmpq   0x60210735
0x60210735:  mov    $0x40008117fe,%rbp
0x6021073f:  mov    %rbp,0x80(%r14)
0x60210746:  mov    $0x7fe2d7c13bc0,%rax
0x60210750:  jmpq   0x622324ce
0x60210755:  jmpq   0x6021075a
0x6021075a:  mov    $0x4000811830,%rbp
0x60210764:  mov    %rbp,0x80(%r14)
0x6021076b:  mov    $0x7fe2d7c13bc1,%rax
0x60210775:  jmpq   0x622324ce

----------------
IN: 
0x00000040008117fe:  mov    0x20f71b(%rip),%rdi        # 0x4000a20f20
0x0000004000811805:  mov    $0x10,%esi
0x000000400081180a:  lea    0xe(%rdi),%r12
0x000000400081180e:  add    $0x10,%rdi
0x0000004000811812:  callq  0x4000801af0

OUT: [size=128]
0x60210780:  mov    $0x4000a20f20,%rbp
0x6021078a:  mov    0x0(%rbp),%rbp
0x6021078e:  mov    $0x10,%ebx
0x60210793:  mov    %ebx,%ebx
0x60210795:  mov    %rbp,%r12
0x60210798:  add    $0xe,%r12
0x6021079c:  add    $0x10,%rbp
0x602107a0:  mov    %rbp,%r13
0x602107a3:  mov    0x20(%r14),%r15
0x602107a7:  add    $0xfffffffffffffff8,%r15
0x602107ab:  mov    $0x4000811817,%r10
0x602107b5:  mov    $0x10,%r11d
0x602107bb:  mov    %r11,0x90(%r14)
0x602107c2:  mov    %rbp,0x98(%r14)
0x602107c9:  mov    %rbx,0x30(%r14)
0x602107cd:  mov    %r13,0x38(%r14)
0x602107d1:  mov    %r12,0x60(%r14)
0x602107d5:  mov    %r10,(%r15)
0x602107d8:  mov    $0x4000801af0,%rbp
0x602107e2:  mov    %rbp,0x80(%r14)
0x602107e9:  mov    $0x9,%ebp
0x602107ee:  mov    %ebp,0xa0(%r14)
0x602107f5:  mov    %r15,0x20(%r14)
0x602107f9:  xor    %eax,%eax
0x602107fb:  jmpq   0x622324ce

----------------
IN: 
0x0000004000811817:  test   %rax,%rax
0x000000400081181a:  je     0x4000811868

OUT: [size=111]
0x60210800:  mov    (%r14),%rbp
0x60210803:  mov    (%r14),%rbx
0x60210806:  and    %rbx,%rbp
0x60210809:  mov    $0x19,%ebx
0x6021080e:  mov    %ebx,0xa0(%r14)
0x60210815:  mov    %rbp,0x98(%r14)
0x6021081c:  test   %rbp,%rbp
0x6021081f:  je     0x6021084a
0x60210825:  jmpq   0x6021082a
0x6021082a:  mov    $0x400081181c,%rbp
0x60210834:  mov    %rbp,0x80(%r14)
0x6021083b:  mov    $0x7fe2d7c13cb0,%rax
0x60210845:  jmpq   0x622324ce
0x6021084a:  jmpq   0x6021084f
0x6021084f:  mov    $0x4000811868,%rbp
0x60210859:  mov    %rbp,0x80(%r14)
0x60210860:  mov    $0x7fe2d7c13cb1,%rax
0x6021086a:  jmpq   0x622324ce

----------------
IN: 
0x000000400081181c:  mov    %r12,(%rax)
0x000000400081181f:  add    $0x10,%rax
0x0000004000811823:  mov    %rax,0x8(%rbx)
0x0000004000811827:  mov    %rbx,%rax
0x000000400081182a:  pop    %rbx
0x000000400081182b:  pop    %rbp
0x000000400081182c:  pop    %r12
0x000000400081182e:  retq   

OUT: [size=180]
0x60210870:  mov    (%r14),%rbp
0x60210873:  mov    0x60(%r14),%rbx
0x60210877:  mov    %rbx,0x0(%rbp)
0x6021087b:  mov    (%r14),%rbp
0x6021087e:  add    $0x10,%rbp
0x60210882:  mov    %rbp,%rbx
0x60210885:  mov    0x18(%r14),%r12
0x60210889:  add    $0x8,%r12
0x6021088d:  mov    %rbx,%r13
0x60210890:  mov    $0x10,%r15d
0x60210896:  mov    %r15,0x90(%r14)
0x6021089d:  mov    %rbp,0x98(%r14)
0x602108a4:  mov    %rbx,(%r14)
0x602108a7:  mov    %r13,(%r12)
0x602108ab:  mov    0x18(%r14),%rbp
0x602108af:  mov    0x20(%r14),%rbx
0x602108b3:  mov    %rbp,(%r14)
0x602108b6:  mov    (%rbx),%rbp
0x602108b9:  mov    0x20(%r14),%rbx
0x602108bd:  add    $0x8,%rbx
0x602108c1:  mov    %rbx,%r12
0x602108c4:  mov    %rbp,0x18(%r14)
0x602108c8:  mov    %rbx,0x20(%r14)
0x602108cc:  mov    (%r12),%rbp
0x602108d0:  mov    0x20(%r14),%rbx
0x602108d4:  add    $0x8,%rbx
0x602108d8:  mov    %rbx,%r12
0x602108db:  mov    %rbx,0x20(%r14)
0x602108df:  mov    %rbp,0x28(%r14)
0x602108e3:  mov    (%r12),%rbp
0x602108e7:  mov    0x20(%r14),%rbx
0x602108eb:  add    $0x8,%rbx
0x602108ef:  mov    %rbx,%r12
0x602108f2:  mov    %rbx,0x20(%r14)
0x602108f6:  mov    %rbp,0x60(%r14)
0x602108fa:  mov    (%r12),%rbp
0x602108fe:  mov    0x20(%r14),%rbx
0x60210902:  add    $0x8,%rbx
0x60210906:  mov    %rbp,0x80(%r14)
0x6021090d:  mov    $0x9,%ebp
0x60210912:  mov    %ebp,0xa0(%r14)
0x60210919:  mov    %rbx,0x20(%r14)
0x6021091d:  xor    %eax,%eax
0x6021091f:  jmpq   0x622324ce

----------------
IN: 
0x0000004000802fb0:  test   %rax,%rax
0x0000004000802fb3:  mov    %rax,%rsi
0x0000004000802fb6:  je     0x4000802ff0

OUT: [size=119]
0x60210930:  mov    (%r14),%rbp
0x60210933:  mov    (%r14),%rbx
0x60210936:  and    %rbx,%rbp
0x60210939:  mov    (%r14),%rbx
0x6021093c:  mov    $0x19,%r12d
0x60210942:  mov    %r12d,0xa0(%r14)
0x60210949:  mov    %rbp,0x98(%r14)
0x60210950:  mov    %rbx,0x30(%r14)
0x60210954:  test   %rbp,%rbp
0x60210957:  je     0x60210982
0x6021095d:  jmpq   0x60210962
0x60210962:  mov    $0x4000802fb8,%rbp
0x6021096c:  mov    %rbp,0x80(%r14)
0x60210973:  mov    $0x7fe2d7c13da0,%rax
0x6021097d:  jmpq   0x622324ce
0x60210982:  jmpq   0x60210987
0x60210987:  mov    $0x4000802ff0,%rbp
0x60210991:  mov    %rbp,0x80(%r14)
0x60210998:  mov    $0x7fe2d7c13da1,%rax
0x602109a2:  jmpq   0x622324ce

----------------
IN: 
0x0000004000802fb8:  mov    0x8(%rax),%rax
0x0000004000802fbc:  mov    $0x1002,%edi
0x0000004000802fc1:  mov    %rax,0x21df88(%rip)        # 0x4000a20f50
0x0000004000802fc8:  mov    %rsi,(%rsi)
0x0000004000802fcb:  mov    $0x9e,%eax
0x0000004000802fd0:  mov    %rsi,0x10(%rsi)
0x0000004000802fd4:  syscall 

OUT: [size=113]
0x602109b0:  mov    (%r14),%rbp
0x602109b3:  add    $0x8,%rbp
0x602109b7:  mov    0x0(%rbp),%rbp
0x602109bb:  mov    $0x1002,%ebx
0x602109c0:  mov    %ebx,%ebx
0x602109c2:  mov    %rbp,%r12
0x602109c5:  mov    $0x4000a20f50,%r13
0x602109cf:  mov    %rbp,(%r14)
0x602109d2:  mov    %rbx,0x38(%r14)
0x602109d6:  mov    %r12,0x0(%r13)
0x602109da:  mov    0x30(%r14),%rbp
0x602109de:  mov    0x30(%r14),%rbx
0x602109e2:  mov    %rbx,0x0(%rbp)
0x602109e6:  mov    $0x9e,%ebp
0x602109eb:  mov    %ebp,%ebp
0x602109ed:  mov    0x30(%r14),%rbx
0x602109f1:  add    $0x10,%rbx
0x602109f5:  mov    0x30(%r14),%r12
0x602109f9:  mov    %rbp,(%r14)
0x602109fc:  mov    %r12,(%rbx)
0x602109ff:  mov    $0x4000802fd4,%rbp
0x60210a09:  mov    %rbp,0x80(%r14)
0x60210a10:  mov    $0x2,%edi
0x60210a15:  callq  0x60081ac0
0x60210a1a:  xor    %eax,%eax
0x60210a1c:  jmpq   0x622324ce

----------------
IN: 
0x0000004000802fd6:  test   %eax,%eax
0x0000004000802fd8:  jne    0x400080300f

OUT: [size=104]
0x60210a30:  mov    (%r14),%rbp
0x60210a33:  mov    (%r14),%rbx
0x60210a36:  and    %rbx,%rbp
0x60210a39:  mov    %rbp,%rbx
0x60210a3c:  mov    %ebx,%ebx
0x60210a3e:  mov    $0x18,%r12d
0x60210a44:  mov    %r12d,0xa0(%r14)
0x60210a4b:  mov    %rbp,0x98(%r14)
0x60210a52:  test   %rbx,%rbx
0x60210a55:  jne    0x60210a80
0x60210a5b:  jmpq   0x60210a60
0x60210a60:  mov    $0x4000802fda,%rbp
0x60210a6a:  mov    %rbp,0x80(%r14)
0x60210a71:  mov    $0x7fe2d7c13e90,%rax
0x60210a7b:  jmpq   0x622324ce
0x60210a80:  mov    $0x400080300f,%rbp
0x60210a8a:  mov    %rbp,0x80(%r14)
0x60210a91:  xor    %eax,%eax
0x60210a93:  jmpq   0x622324ce

----------------
IN: 
0x0000004000802fda:  movb   $0x1,0x21e077(%rip)        # 0x4000a21058
0x0000004000802fe1:  jmpq   0x4000802f4b

OUT: [size=55]
0x60210aa0:  mov    $0x1,%ebp
0x60210aa5:  mov    $0x4000a21058,%rbx
0x60210aaf:  mov    %bpl,(%rbx)
0x60210ab2:  jmpq   0x60210ab7
0x60210ab7:  mov    $0x4000802f4b,%rbp
0x60210ac1:  mov    %rbp,0x80(%r14)
0x60210ac8:  mov    $0x7fe2d7c13f08,%rax
0x60210ad2:  jmpq   0x622324ce

----------------
IN: 
0x0000004000802f4b:  mov    %rsi,%rax
0x0000004000802f4e:  pop    %rbx
0x0000004000802f4f:  retq   

OUT: [size=63]
0x60210ae0:  mov    0x30(%r14),%rbp
0x60210ae4:  mov    0x20(%r14),%rbx
0x60210ae8:  mov    %rbp,(%r14)
0x60210aeb:  mov    (%rbx),%rbp
0x60210aee:  mov    0x20(%r14),%rbx
0x60210af2:  add    $0x8,%rbx
0x60210af6:  mov    %rbx,%r12
0x60210af9:  mov    %rbp,0x18(%r14)
0x60210afd:  mov    %rbx,0x20(%r14)
0x60210b01:  mov    (%r12),%rbp
0x60210b05:  mov    0x20(%r14),%rbx
0x60210b09:  add    $0x8,%rbx
0x60210b0d:  mov    %rbp,0x80(%r14)
0x60210b14:  mov    %rbx,0x20(%r14)
0x60210b18:  xor    %eax,%eax
0x60210b1a:  jmpq   0x622324ce

----------------
IN: 
0x0000004000804c7c:  mov    %rax,-0x100(%rbp)
0x0000004000804c83:  jmpq   0x4000803f77

OUT: [size=42]
0x60210b20:  mov    0x28(%r14),%rbp
0x60210b24:  add    $0xffffffffffffff00,%rbp
0x60210b2b:  mov    (%r14),%rbx
0x60210b2e:  mov    %rbx,0x0(%rbp)
0x60210b32:  mov    $0x4000803f77,%rbp
0x60210b3c:  mov    %rbp,0x80(%r14)
0x60210b43:  xor    %eax,%eax
0x60210b45:  jmpq   0x622324ce

----------------
IN: 
0x0000004000803f77:  cmpq   $0x0,0x21d0d1(%rip)        # 0x4000a21050
0x0000004000803f7f:  jne    0x4000803fc4

OUT: [size=129]
0x60210b50:  mov    $0x4000a21050,%rbp
0x60210b5a:  mov    0x0(%rbp),%rbp
0x60210b5e:  sub    $0x0,%rbp
0x60210b62:  mov    $0x11,%ebx
0x60210b67:  mov    %ebx,0xa0(%r14)
0x60210b6e:  xor    %ebx,%ebx
0x60210b70:  mov    %rbx,0x90(%r14)
0x60210b77:  mov    %rbp,0x98(%r14)
0x60210b7e:  test   %rbp,%rbp
0x60210b81:  jne    0x60210bac
0x60210b87:  jmpq   0x60210b8c
0x60210b8c:  mov    $0x4000803f81,%rbp
0x60210b96:  mov    %rbp,0x80(%r14)
0x60210b9d:  mov    $0x7fe2d7c14070,%rax
0x60210ba7:  jmpq   0x622324ce
0x60210bac:  jmpq   0x60210bb1
0x60210bb1:  mov    $0x4000803fc4,%rbp
0x60210bbb:  mov    %rbp,0x80(%r14)
0x60210bc2:  mov    $0x7fe2d7c14071,%rax
0x60210bcc:  jmpq   0x622324ce

----------------
IN: 
0x0000004000803f81:  mov    0x21be58(%rip),%rax        # 0x4000a1fde0
0x0000004000803f88:  mov    (%rax),%rdx
0x0000004000803f8b:  mov    %rdx,-0x78(%rbp)
0x0000004000803f8f:  mov    %rdx,%fs:0x28
0x0000004000803f98:  cmpl   $0x0,0x21bcd5(%rip)        # 0x4000a1fc74
0x0000004000803f9f:  je     0x4000803fb9

OUT: [size=198]
0x60210be0:  mov    $0x4000a1fde0,%rbp
0x60210bea:  mov    0x0(%rbp),%rbp
0x60210bee:  mov    %rbp,%rbx
0x60210bf1:  mov    %rbp,(%r14)
0x60210bf4:  mov    (%rbx),%rbp
0x60210bf7:  mov    0x28(%r14),%rbx
0x60210bfb:  add    $0xffffffffffffff88,%rbx
0x60210bff:  mov    %rbp,%r12
0x60210c02:  mov    %rbp,0x10(%r14)
0x60210c06:  mov    %r12,(%rbx)
0x60210c09:  mov    0x118(%r14),%rbp
0x60210c10:  mov    $0x28,%ebx
0x60210c15:  add    %rbp,%rbx
0x60210c18:  mov    0x10(%r14),%rbp
0x60210c1c:  mov    %rbp,(%rbx)
0x60210c1f:  mov    $0x4000a1fc74,%rbp
0x60210c29:  mov    0x0(%rbp),%ebp
0x60210c2c:  sub    $0x0,%rbp
0x60210c30:  mov    %rbp,%rbx
0x60210c33:  mov    %ebx,%ebx
0x60210c35:  mov    $0x10,%r12d
0x60210c3b:  mov    %r12d,0xa0(%r14)
0x60210c42:  xor    %r12d,%r12d
0x60210c45:  mov    %r12,0x90(%r14)
0x60210c4c:  mov    %rbp,0x98(%r14)
0x60210c53:  test   %rbx,%rbx
0x60210c56:  je     0x60210c81
0x60210c5c:  jmpq   0x60210c61
0x60210c61:  mov    $0x4000803fa1,%rbp
0x60210c6b:  mov    %rbp,0x80(%r14)
0x60210c72:  mov    $0x7fe2d7c140e8,%rax
0x60210c7c:  jmpq   0x622324ce
0x60210c81:  jmpq   0x60210c86
0x60210c86:  mov    $0x4000803fb9,%rbp
0x60210c90:  mov    %rbp,0x80(%r14)
0x60210c97:  mov    $0x7fe2d7c140e9,%rax
0x60210ca1:  jmpq   0x622324ce

----------------
IN: 
0x0000004000803f81:  mov    0x21be58(%rip),%rax        # 0x4000a1fde0
0x0000004000803f88:  mov    (%rax),%rdx
0x0000004000803f8b:  mov    %rdx,-0x78(%rbp)
0x0000004000803f8f:  mov    %rdx,%fs:0x28
0x0000004000803f98:  cmpl   $0x0,0x21bcd5(%rip)        # 0x4000a1fc74
0x0000004000803f9f:  je     0x4000803fb9