Re: Stack segments for Aarch64

[Luis Machado via Gdb <gdb@sourceware.org>]

Right, "maint info sections" would complement "info proc mapping", if you want to have the visibility of all
the interacting pieces in exec, core file and memory.

On 6/6/24 11:27, Phil Phil wrote:
> Would you suggest that the output of maintenance info sections is more "complete" if you want to see all mapped memory regions?
> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
> *From:* Luis Machado <luis.machado@arm.com>
> *Sent:* Thursday, June 6, 2024 10:15 AM
> *To:* Phil Phil <heidegg@hotmail.com>; gdb@sourceware.org <gdb@sourceware.org>
> *Subject:* Re: Stack segments for Aarch64
>  
> On 6/6/24 10:57, Phil Phil wrote:
>> Should the stack segment still be there though? I compared a stackpointer to the memory areas from info proc mappings and I can't find a match. 
> 
> You'll likely find it in a core file section instead: maint info sections.
> 
> For me:
> 
>  [28]     0xfffffffdf000->0x1000000000000 at 0x00191350: load13 ALLOC LOAD HAS_CONTENTS
> 
> Does that help? GDB will look things up in the core file instead of memory, which is probably
> why the way it displays things is slightly different.
> 
> It could be improved I suppose.
> 
>> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>> *From:* Luis Machado <luis.machado@arm.com>
>> *Sent:* Thursday, June 6, 2024 9:41 AM
>> *To:* Phil Phil <heidegg@hotmail.com>; gdb@sourceware.org <gdb@sourceware.org>
>> *Subject:* Re: Stack segments for Aarch64
>>  
>> Hi,
>> 
>> On 6/6/24 10:33, Phil Phil wrote:
>>> GDB 12.1 coredump post mortem coredump debugging on an x64 Linux desktop.  I do not see a perms column in info proc mappings.
>>> 
>> 
>> Ah, so it is corefile debugging. Checking on my end, I don't see the permissions column either. Now it escapes me if we have any
>> special reason for that or if it is just an oversight somewhere. As for the stack marker, I suppose we lose that reference
>> when the corefile is generated. That reference comes from /proc/<pid>/maps when we do "info proc mapping".
>> 
>> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>>> *From:* Luis Machado <luis.machado@arm.com>
>>> *Sent:* Thursday, June 6, 2024 9:23 AM
>>> *To:* Phil Phil <heidegg@hotmail.com>; gdb@sourceware.org <gdb@sourceware.org>
>>> *Subject:* Re: Stack segments for Aarch64
>>>  
>>> Hi,
>>> 
>>> On 6/6/24 10:17, Phil Phil via Gdb wrote:
>>>> Greetings,
>>>> 
>>>> I'm trying get some memory info on an Aarch64 for a coredump. The aarch64 gdb produces this output for info proc mappings
>>>> 
>>>>           Start Addr           End Addr       Size     Offset objfile
>>>>         0x557ead9000       0x5582dee000  0x4315000        0x0 /usr/bin/myproc
>>>>         0x5582dfe000       0x5582f0a000   0x10c000  0x4315000 /usr/bin/myproc
>>>>         0x5582f0a000       0x5582f24000    0x1a000  0x4421000 /usr/bin/myproc
>>>> 
>>>> I'm missing at least two things here compared to the x64 output:
>>>> 
>>>> 
>>>>   *
>>>> No read/write permissions
>>>>   *
>>>> Stack segments are not shown.
>>>> 
>>>> Any ideas on how to make these two things visible on Aarch64?
>>>> 
>>>> Regards
>>> 
>>> What aarch64 debugging setup do you have? Versions etc? Remote?
>>> 
>>> For me, running native gdb on aarch64:
>>> 
>>> process 1681741
>>> Mapped address spaces:
>>> 
>>>           Start Addr           End Addr       Size     Offset  Perms  objfile
>>>       0xaaaaaaaa0000     0xaaaaac3c6000  0x1926000        0x0  r-xp   /home/ubuntu/work/build/binutils-gdb-master/gdb/gdb
>>>       0xaaaaac3d5000     0xaaaaacd2a000   0x955000  0x1925000  r--p   /home/ubuntu/work/build/binutils-gdb-master/gdb/gdb
>>>       0xaaaaacfc6000     0xaaaaad069000    0xa3000        0x0  rw-p   [heap]
>>> ...
>>>       0xfffffffdf000    0x1000000000000    0x21000        0x0  rw-p   [stack]
>> 
>