Re: Fwd: vdso

[vijay nag <vijunag@gmail.com>]

On Mon, Jul 8, 2013 at 2:17 PM, Jan Kratochvil
<jan.kratochvil@redhat.com> wrote:
> On Mon, 08 Jul 2013 08:50:49 +0200, vijay nag wrote:
>> Breakpoint 1, linux_proc_xfer_partial (ops=0x8499230, object=TARGET_OBJECT_MEMORY, annex=0x0, readbuf=0xbffff250 "\r", writebuf=0x0, offset=4294967296, len=4294959104)
>>     at linux-nat.c:4386
>> 4386    if (object != TARGET_OBJECT_MEMORY || !readbuf)
>> (gdb) p /x offset
>> $3 = 0xffffe000
>> (gdb) p /x len
>> $4 = 0x34
>
> offset and len in the first line correspond to offset 0x100000000
> and len 0xffffe000 resp.  So I do not see the values you printed from GDB
> below.
>
> This is general debugging of GDB, it no longer belongs to this list.
> You should best file it to GDB Bugzilla and try to provide reproducibility
> information.
>
>
> There seems to be some 32->64bit extension problem (0x100000000).  Isn't the
> GDB built for x86_64 target while you run it for i386 target?  This sure
> should work but there may be some issues.  Try to build 32-bit host GDB as
> troubleshooting:
>         CFLAGS=-m32 ./configure i386-unknown-linux-gnu
> But this is already rather for the Bugzilla.
>
>
> Jan
I've built 32 bit gdb configured for i686-pc-linux-gnu and my kernel
too is 32 bit one.

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uname -a
Linux 2.6.18-myos-v2-38059-deb #1 SMP Sun Apr 3 01:48:20 EDT 2011 i686 GNU/Linux

Are you saying that gdb is miscalculating offset of vdso ?