From: Jan Kiszka <jan.kiszka@siemens.com>
To: Neo Jia <neojia@gmail.com>
Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: qemu "info registers" doesn't match the one I saw from kgdb?
Date: Thu, 19 Feb 2009 10:39:58 +0100 [thread overview]
Message-ID: <499D28EE.6050309@siemens.com> (raw)
In-Reply-To: <5d649bdb0902190055n7e4098fek479f60158d61246e@mail.gmail.com>
Neo Jia wrote:
> hi,
>
> I am seeing something different between "info registers" from qemu
> monitor window vs. kgdb. This is a 32-bit Linux guest running on
> KVM-84.
>
> When I just break into the guest kernel with kgdb, I tried the
> follwoing commands:
>
> (qemu) info registers
> EAX=00010060 EBX=c0471e3c ECX=00000000 EDX=000002fd
> ESI=000002fd EDI=c04c5d20 EBP=c0471ddc ESP=c0471ddc
> EIP=c021129b EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0
> ES =007b 00000000 ffffffff 00c0f300
> CS =0060 00000000 ffffffff 00c09b00
> SS =0068 00000000 ffffffff 00c09300
> DS =007b 00000000 ffffffff 00c0f300
> FS =0000 00000000 ffffffff 00000000
> GS =0000 00000000 ffffffff 00000000
> LDT=0000 00000000 ffffffff 00000000
> TR =0000 00000000 0000ffff 00008b00
> GDT= c0407a80 000000ff
> IDT= c0464000 000007ff
> CR0=80050033 CR2=00000000 CR3=004aa000 CR4=00000000
> DR0=00000000 DR1=00000000 DR2=00000000 DR3=00000000
> DR6=ffff0ff0 DR7=00000400
> FCW=037f FSW=0000 [ST=0] FTW=00 MXCSR=00000000
> 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
>
> But from Windbg, I got:
>
> (gdb) info registers
> eax 0x0 0x0
> ecx 0xc 0xc
> edx 0x0 0x0
> ebx 0x0 0x0
> esp 0xc0471f14 0xc0471f14
> ebp 0xc0471fc0 0xc0471fc0
> esi 0xc04ac07a 0xc04ac07a
> edi 0xc04ad1f9 0xc04ad1f9
> eip 0xc047a853 0xc047a853 <setup_arch+1036>
> eflags 0x86 [ PF SF ]
> cs 0x60 0x60
> ss 0x68 0x68
> ds 0xc049007b 0xc049007b
> es 0x7b 0x7b
> fs 0xffff 0xffff
> gs 0xffff 0xffff
>
> So, which one is correct? Do we still maintain the "info registers" on qemu?
Yes, we do maintain them (for now only in the kvm tree, upstream is yet
lacking a few patches). But you have to keep in mind that, when you take
a snapshot of the guest running inside Windbg via "info registers" (or
via the built-in gdbstub), you actually debug Windbg itself, no longer
the guest kernel code Windbg is interrupting. That's why you see
different EIP values...
Jan
--
Siemens AG, Corporate Technology, CT SE 2
Corporate Competence Center Embedded Linux
prev parent reply other threads:[~2009-02-19 9:40 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-02-19 8:55 qemu "info registers" doesn't match the one I saw from kgdb? Neo Jia
2009-02-19 9:39 ` Jan Kiszka [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=499D28EE.6050309@siemens.com \
--to=jan.kiszka@siemens.com \
--cc=kvm@vger.kernel.org \
--cc=neojia@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox