Re: FreeBSD boot hangs on qemu-kvm on AMD host

[Michael Tokarev <mjt@tls.msk.ru>]

09.03.2011 15:50, Avi Kivity wrote:
> On 03/09/2011 02:06 PM, Michael Tokarev wrote:
>> Hello.
>>
>> Dominik Klein (Cc'd) reported on irc that current
>> FreeBSD release hangs at boot in qemu-kvm.  It is
>> trivially verifiable by d/loading the bootonly
>> FreeBSD 8.2 CD image from ftp.freebsd.org and
>> running
>>
>>    kvm -cdrom FreeBSD-8.2-RELEASE-amd64-bootonly.iso.
>>
[]
>> So far the 3 affected systems where we tried this are all
>> AMD machines.  My home box is AthlonII, my work box is
>> PhenomI 9750, and Dominik tries it on Opteron 6174.

I also tried on another AMD machine, with TurionI, -- the same
effect.

> Can't reproduce.  What host kernel version are you using?

And this is a very good question, this is what I forgot to
mention.

It hangs here - in all cases - with 2.6.37+ kernels.  I
tried 2.6.35 on one of my boxes, and there it works just
fine.  We're testing various kernels now, or trying to.

So I'm not sure anymore it's actually AMD-specific, but at
least one person tried debian 2.6.37-2-amd64 kernel on
a core-i7 box and that combination works.

> Please post the output of
> 
>   info register

And this is where the most fun begins.  Right after `info registers'
it "unhangs" and continues as if nothing happened, ...

>   x/50i $eip-30

...so I can't get this information anymore.  Here it goes with
an explicit "stop", fwiw:

$ kvm -monitor stdio -cdrom /stage/tmp/FreeBSD-8.2-RELEASE-i386-bootonly.iso
QEMU 0.14.0 monitor - type 'help' for more information

(qemu) stop

(qemu) info registers
EAX=00000042 EBX=00009f8b ECX=00000042 EDX=00005dd0
ESI=00000001 EDI=0000c350 EBP=00000000 ESP=00005d9c
EIP=0000f3b4 EFL=00000246 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
ES =9f40 0009f400 ffffffff 00c09300
CS =f000 000f0000 0000ffff 00009b00
SS =0000 00000000 ffffffff 00c09300
DS =0000 00000000 ffffffff 00c09300
FS =0000 00000000 ffffffff 00c0f300
GS =0000 00000000 ffffffff 00c0f300
LDT=0000 00000000 0000ffff 00008200
TR =0038 00005f98 00002067 00008b00
GDT=     00009590 0000003f
IDT=     00000000 000003ff
CR0=00000010 CR2=00000000 CR3=00000000 CR4=00000000
DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 DR3=0000000000000000
DR6=00000000ffff0ff0 DR7=0000000000000400
EFER=0000000000000000
FCW=037f FSW=0000 [ST=0] FTW=00 MXCSR=00001f80
FPR0=0000000000000000 0000 FPR1=0000000000000000 0000
FPR2=0000000000000000 0000 FPR3=0000000000000000 0000
FPR4=0000000000000000 0000 FPR5=0000000000000000 0000
FPR6=0000000000000000 0000 FPR7=0000000000000000 0000
XMM00=00000000000000000000000000000000 XMM01=00000000000000000000000000000000
XMM02=00000000000000000000000000000000 XMM03=00000000000000000000000000000000
XMM04=00000000000000000000000000000000 XMM05=00000000000000000000000000000000
XMM06=00000000000000000000000000000000 XMM07=00000000000000000000000000000000

(qemu) x/50i $eip-30
0x000000000000f396:  add    0xc(%di),%ax
0x000000000000f399:  add    -0xb0(%di),%ax
0x000000000000f39d:  (bad)
0x000000000000f39e:  decw   0x6885(%bx,%di)
0x000000000000f3a2:  (bad)
0x000000000000f3a3:  (bad)
0x000000000000f3a4:  ljmp   *<internal disassembler error>
0x000000000000f3a6:  out    %al,$0xfe
0x000000000000f3a8:  (bad)
0x000000000000f3a9:  decw   0x856(%bp,%di)
0x000000000000f3ad:  mov    %dx,-0xb0(%di)
0x000000000000f3b1:  (bad)
0x000000000000f3b2:  ljmp   *<internal disassembler error>
0x000000000000f3b4:  jnp    0xf3b5
0x000000000000f3b6:  (bad)
0x000000000000f3b7:  ljmp   *(%bx,%di)
0x000000000000f3b9:  rorw   %cl,0xc45(%bp,%di)
0x000000000000f3bd:  mov    %bx,0x24(%si)
0x000000000000f3c0:  add    $0x3,%al
0x000000000000f3c2:  inc    %si
0x000000000000f3c3:  or     %al,(%bx,%di)
0x000000000000f3c5:  rorb   0x2404(%bx,%di)
0x000000000000f3c9:  call   0xd58e
0x000000000000f3cc:  (bad)
0x000000000000f3cd:  decw   0x1446(%bp,%di)
0x000000000000f3d1:  mov    %ax,-0xb4(%di)
0x000000000000f3d5:  (bad)
0x000000000000f3d6:  ljmp   *<internal disassembler error>
0x000000000000f3d8:  and    %bh,%bh
0x000000000000f3da:  (bad)
0x000000000000f3db:  decw   0x29d8(%bx,%di)
0x000000000000f3df:  fiaddl (%bp,%di)
0x000000000000f3e1:  inc    %si
0x000000000000f3e2:  add    $0xc7,%al
0x000000000000f3e4:  inc    %sp
0x000000000000f3e5:  and    $0x10,%al
0x000000000000f3e7:  add    %al,(%bx,%si)
0x000000000000f3e9:  add    %al,(%bx,%si)
0x000000000000f3eb:  mov    %dx,0x24(%si)
0x000000000000f3ee:  or     %cl,0x2444(%bx,%di)
0x000000000000f3f2:  or     $0x8b,%al
0x000000000000f3f4:  inc    %bp
0x000000000000f3f5:  or     $0x3,%al
0x000000000000f3f7:  inc    %si
0x000000000000f3f8:  or     %al,(%bx,%di)
0x000000000000f3fa:  fmuls  0x2444(%bx,%di)
0x000000000000f3fe:  add    $0x8b,%al
0x000000000000f400:  inc    %bp
0x000000000000f401:  movsb  %ds:(%si),%es:(%di)
0x000000000000f402:  mov    %ax,(%si)
(qemu) _

Thanks!

/mjt