Re: [alsa-devel] [PATCH] ASoC: rt5645: fix build warning

From: Jarkko Nikula
Date: Thu Oct 08 2015 - 10:33:33 EST


On 10/08/2015 11:55 AM, Sudip Mukherjee wrote:
On Wed, Oct 07, 2015 at 03:05:27PM +0100, Mark Brown wrote:
On Wed, Oct 07, 2015 at 05:52:12PM +0530, Sudip Mukherjee wrote:
We were getting build warning about "Section mismatch".
dmi_platform_intel_broadwell is being referenced from the probe function
rt5645_i2c_probe(), but dmi_platform_intel_broadwell was marked with
__initdata.

Signed-off-by: Sudip Mukherjee <sudip@xxxxxxxxxxxxxxx>

-static struct dmi_system_id dmi_platform_intel_broadwell[] __initdata = {
+static struct dmi_system_id dmi_platform_intel_broadwell[] = {

This doesn't seem like the obvious fix - why are we not annotating the
probe function suitably (or alternatively if we can't why does
__initdata still exist)?

probe function should not be __init. probe can be called anytime after
the module has been loaded.
__initdata still exists as that part of the code was added by
e9159e7577cf ("ASoC: rt5645: Add dmi for Broadwell") which is a very
recent modification and I think that has been added by mistake.
One more argument in my favor:
The use in probe function is
if (dmi_check_system(dmi_platform_intel_braswell) ||
dmi_check_system(dmi_platform_intel_broadwell))

dmi_platform_intel_braswell is not marked as __initdata but
dmi_platform_intel_broadwell is marked but they both have same use at
the same place.

If one really wants to save a few bytes then one could annotate this it with __initdata_or_module (very low use in kernel) but I don't think it's worth of effort and probably should be done for other sections here too by another patch.

To me this patch looks a right thing to do at the moment.

Reviewed-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/