Re: [PATCH v4 0/7] elf: add better bootm support

["Clément Leger" <cleger@kalray.eu>]

Hi Oleksij,

----- On 9 May, 2020, at 18:51, Oleksij Rempel o.rempel@pengutronix.de wrote:

> On Sat, May 09, 2020 at 04:51:42PM +0200, Oleksij Rempel wrote:
>> Hi Clement,
>> 
>> suddenly it is still exploding. I'll try to investigate the reason.
> 
> common/elf.c:
>  load_elf_image_phdr()
>    elf_hdr_e_phnum() <-- returns 0
>    for (i = 0; i < elf_hdr_e_phnum(elf, buf) ; ++i) {
>      ... so we will never get here.
> 
> Probably we should add a sanity check here and be more verbose in this
> case.

There is something odd because your elf is correct and has 2 program
headers. So this should not be a problem (but a sanity check makes
sense !).

I suspect that the elf size computation is wrong with your elf file
and leads to incompletely loaded elf file but I tried to compute
it using the sequence of code used in barebox and everything seems ok.
Maybe there is something with the endianess/elfclass going wrong.
I tried again on kvx to be sure I did not made a mistake but it works
and the elf entry address is correctly used.
I'll try to add handling for different endianess and load your elf
file on kvx to debug that.

> 
> here is my elf image:
> https://github.com/olerem/barebox/blob/new-elf/ore-linux-dpt-module

I succeeded in building Distrokit images but I can't get it under barebox.
There is only 4M oof RAM and each time I tries to modify it, it won't boot
anymore.
I tried integrating the kernel (and your eore-linux-dpt-module elf) in
the environment but it also won't boot. Do you have any idea on how to
do it ?
Even if the kernel won't start under qemu , at least I'll be able to
understand what is wrong.

Thanks for testing,

Clément

> 
>> On Fri, May 08, 2020 at 07:04:04PM +0200, Clement Leger wrote:
>> > Currently, when booting an elf file using "bootm /dev/mtdx", bootm will
>> > simply pass the file to the bootm and the read done on it will read the
>> > entire flash partition. This series starts by some cleanup and then add an
>> > elf_open function to load the elf file size only based on the elf header.
>> > A special handling for the elf file is also added in bootm data to allow
>> > using directly the elf file structure. Finally the mips bootm is modified
>> > to use bootm_load_os directly instead of manual elf loading.
>> > 
>> > Compilation for both mips and arm has been tested but run on qemu-malta was not
>> > possible. Changing the MALLOC_SIZE to allow loading a kernel always lead to a
>> > non-bootable system. Changes have been tested on kvx architecture for which
>> > bootm support has been added and will be submitted.
>> > 
>> > Changes v3 -> v4
>> >  - Fix init of elf entry address to be used by bootm_load_elf
>> > 
>> > Changes v2 -> v3
>> >  - Integrate elf loading in bootm_load_os
>> >  - Add patch to remove now unused elf_load_image/elf_release_image
>> >  - Use malloc instead of xmalloc and check return value
>> > 
>> > Changes v1 -> v2
>> >  - Add BOOTM_ELF config to select elf support and add checks in code
>> >  - Add an elf_get_mem_size function to avoid computing elf size in bootm.c
>> >  - Use xmalloc and read_full in elf_open instead of xzalloc/read
>> >  - Fix data->elf NULL reset
>> >  - Remove elf struct entirely from mips bootm code
>> > 
>> > Clement Leger (7):
>> >   common: elf: add computation of elf boundaries
>> >   common: elf: fix warning on 32 bits architectures
>> >   common: elf: split init to be reused from other function
>> >   common: elf: add elf_open, elf_close and elf_load
>> >   common: bootm: add support for elf file loading
>> >   mips: lib: bootm: use bootm elf loading capabilities
>> >   common: elf: remove elf_load_image/elf_release_image
>> > 
>> >  arch/mips/lib/bootm.c |  31 +++++-------
>> >  common/Kconfig        |   8 +++
>> >  common/bootm.c        |  33 +++++++++++++
>> >  common/elf.c          | 111 +++++++++++++++++++++++++++++++++++-------
>> >  include/bootm.h       |   3 ++
>> >  include/elf.h         |  16 +++++-
>> >  6 files changed, 163 insertions(+), 39 deletions(-)
>> > 
>> > --
>> > 2.17.1
>> > 
>> > 
>> > _______________________________________________
>> > barebox mailing list
>> > barebox@lists.infradead.org
>> > http://lists.infradead.org/mailman/listinfo/barebox
>> > 
>> 
>> --
>> Pengutronix e.K.                           |                             |
>> Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
>> 31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
>> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |
> 
> 
> 
> --
> Pengutronix e.K.                           |                             |
> Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
> 31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox