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Re: Bug in i386_process_record?


Michael Snyder wrote:
Hui Zhu wrote:
On Wed, Aug 26, 2009 at 02:42, Eli Zaretskii<eliz@gnu.org> wrote:
From: Hui Zhu <teawater@gmail.com>
Date: Tue, 25 Aug 2009 13:02:44 +0800
Cc: msnyder@vmware.com, gdb-patches@sourceware.org

It seems that the segment (It is not the section)  registers in x86
protect mode is just help MMU to get the physical address.  It's
transparent for the user level program.
It's transparent if $es and $ds have the same value (which they
usually do, AFAIK).

What do you think about remove this warning from this patch?
I would indeed do that, if we find that $es and $ds have the same
values.  Assuming that someone who knows Linux better than I do
confirms that these two registers hold the same selector when a normal
application is running in user mode.

Thanks for remind me.  We cannot get the value of each segment
register, but we can get each segment register point to.  So if the
value of segment registers, it's means that the value of them is same.

I add some code about it:
          regcache_raw_read_unsigned (ir.regcache,
                                      ir.regmap[X86_RECORD_ES_REGNUM],
                                      &es);
          regcache_raw_read_unsigned (ir.regcache,
                                      ir.regmap[X86_RECORD_DS_REGNUM],
                                      &ds);
          if (ir.aflag && (es != ds))
            {

After that, we will not get the warning because the es is same with ds
in user level.

What do you think about it?

I think it is the best version I have seen so far. And it seems to follow the conclusions of the discussion. And I've tested it, and it seems to work.

I would say wait until end-of-business Friday, and
if there are no more comments, check it in!

Hui,


Do you think you could add some new tests to i386-reverse.exp,
to verify the string instructions?

Thanks,
Michael


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