From: Anthony Liguori <anthony@codemonkey.ws>
To: qemu-devel@nongnu.org
Cc: Jan Kiszka <jan.kiszka@siemens.com>, Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH v5 18/18] gdbstub: x86: Switch 64/32 bit registers dynamically
Date: Tue, 18 Nov 2008 15:45:26 -0600 [thread overview]
Message-ID: <49233776.9050504@codemonkey.ws> (raw)
In-Reply-To: <492334B9.3010705@codemonkey.ws>
Anthony Liguori wrote:
> Jan Kiszka wrote:
>> Commit 5459 broke gdbstub's dynamic register set switching between
>> x86-64 and i386. That prevents setting the correct architecture in gdb
>> when debugging 32 or 16-bit code in a 64-bit emulator. This patch
>> reintroduces the feature over previous refactorings.
>>
>
> How does this interact with SMP? If you have one VCPU in 32-bit mode
> and another in 64-bit mode, won't that confuse GDB?
After talking to Paul in IRC, it seems that GDB is going to make
assumptions that all threads share an address space and potentially
cache memory accesses or at least be sloppy with how it does memory
accesses.
I think this is a pretty strong argument for using fork instead of
threads. I would think you should be able to provoke this pretty easily
with an SMP guest.
Regards,
Anthony Liguori
> Regards,
>
> Anthony Liguori
>
>
>>
>>
>
next prev parent reply other threads:[~2008-11-18 21:45 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-17 16:18 [Qemu-devel] [PATCH v5 00/18] Enhance debugging support Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 06/18] Respect length of watchpoints Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 04/18] Refactor and enhance break/watchpoint API Jan Kiszka
2008-11-18 19:59 ` Anthony Liguori
2008-11-18 22:24 ` [Qemu-devel] " Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 02/18] Refactor translation block CPU state handling Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 01/18] Convert CPU_PC_FROM_TB to static inline Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 05/18] Set mem_io_vaddr on io_read Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 03/18] gdbstub: Return appropriate watch message to gdb Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 07/18] Restore pc on watchpoint hits Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 08/18] Remove premature memop TB terminations Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 16/18] gdbstub: x86: Refactor register access Jan Kiszka
2008-11-18 21:15 ` Anthony Liguori
2008-11-18 23:12 ` [Qemu-devel] " Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 10/18] Introduce BP_WATCHPOINT_HIT flag Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 15/18] gdbstub: Add vCont support Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 14/18] x86: Dump debug registers Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 17/18] gdbstub: x86: Support for setting segment registers Jan Kiszka
2008-11-18 21:19 ` Anthony Liguori
2008-11-18 23:15 ` [Qemu-devel] " Jan Kiszka
2008-11-19 14:24 ` Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 11/18] Add debug exception hook Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 12/18] Introduce BP_CPU as a breakpoint type Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 18/18] gdbstub: x86: Switch 64/32 bit registers dynamically Jan Kiszka
2008-11-18 21:21 ` Anthony Liguori
2008-11-18 21:33 ` Anthony Liguori
2008-11-18 21:45 ` Anthony Liguori [this message]
2008-11-18 22:37 ` [Qemu-devel] " Jan Kiszka
2008-11-18 22:46 ` Paul Brook
2008-11-18 23:07 ` Jan Kiszka
2008-11-18 23:23 ` Paul Brook
2008-11-18 23:38 ` Jan Kiszka
2008-11-19 0:06 ` Paul Brook
2008-11-19 9:38 ` Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 09/18] gdbstub: manage CPUs as threads Jan Kiszka
2008-11-17 16:18 ` [Qemu-devel] [PATCH v5 13/18] x86: Debug register emulation Jan Kiszka
2008-11-18 21:26 ` [Qemu-devel] [PATCH v5 00/18] Enhance debugging support Anthony Liguori
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=49233776.9050504@codemonkey.ws \
--to=anthony@codemonkey.ws \
--cc=jan.kiszka@siemens.com \
--cc=paul@codesourcery.com \
--cc=qemu-devel@nongnu.org \
/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;
as well as URLs for NNTP newsgroup(s).