Re: [PATCH v4 1/2] remoteproc: elf_loader: Update resource table name check

From: Mathieu Poirier
Date: Wed Jan 04 2023 - 18:25:59 EST


On Wed, Dec 21, 2022 at 11:40:32AM +0530, Srinivasa Rao Mandadapu wrote:
> Update the way of checking resource table name with prefix substring search
> instead of complete string search.
>
> In general, Qualcomm DSP binary is prepared by combining different ELFs'.
> Hence, section header name (e.g. .resource_table), appended with ELF name
> to differentiate with same section(e.g. resource_table.ac_bin_process) of
> different ELFs'.
>

Well, they are different ELF files so it is implied the resource section may be
different... And from what I see this is purely a human thing and not
specifically needed by machines.

I can't imagine this is a new situation and as such must ask how it was working
before?

> Example readelf output of DSP binary:
> [60] .start.ac_bin_process PROGBITS
> [61] .resource_table.ac_bin_process PROGBITS

The real question is... Why is this labeled ".resource_table.ac_bin_process"
rather than simply ".resource_table"?

> [62] .comment.ac_bin_process PROGBITS
>
> Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@xxxxxxxxxxx>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
> Reviewed-by: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>
> ---
> drivers/remoteproc/remoteproc_elf_loader.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/remoteproc/remoteproc_elf_loader.c b/drivers/remoteproc/remoteproc_elf_loader.c
> index 5a412d7..77330d6 100644
> --- a/drivers/remoteproc/remoteproc_elf_loader.c
> +++ b/drivers/remoteproc/remoteproc_elf_loader.c
> @@ -272,7 +272,7 @@ find_table(struct device *dev, const struct firmware *fw)
> u64 offset = elf_shdr_get_sh_offset(class, shdr);
> u32 name = elf_shdr_get_sh_name(class, shdr);
>
> - if (strcmp(name_table + name, ".resource_table"))
> + if (!strstarts(name_table + name, ".resource_table"))
> continue;
>
> table = (struct resource_table *)(elf_data + offset);
> --
> 2.7.4
>