Date: Mon, 13 Mar 2017 14:46:09 -0400
From: Jessica Yu <jeyu@redhat.com>
To: David Daney <david.daney@cavium.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>,
        Andrey Ryabinin <a.ryabinin@samsung.com>, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] module: set .init_array alignment to 8
Message-ID: <20170313184609.GC8117@packer-debian-8-amd64.digitalocean.com>
References: <20170308013108.13345-1-david.daney@cavium.com>
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+++ David Daney [07/03/17 17:31 -0800]:
>The proper idiom for aligning linker sections in modules is different
>than for built-in sections.  ". = ALIGN();" followed by a forced
>output address of 0 does nothing, as forcing the address changes the
>value of ".".
>
>Use output section alignment specifier instead.
>
>Fixes: 9ddf82521c86 ("kernel: add support for .init_array.* constructors")
>Signed-off-by: David Daney <david.daney@cavium.com>

Good catch, thanks. I've applied this to modules-next.

Jessica

>I noticed this when doing the __jump_table thing.  Doesn't seem to
>break a defconfig build, but otherwise untested.
>
> scripts/module-common.lds | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
>diff --git a/scripts/module-common.lds b/scripts/module-common.lds
>index 9b6e246..d61b9e8 100644
>--- a/scripts/module-common.lds
>+++ b/scripts/module-common.lds
>@@ -20,8 +20,7 @@ SECTIONS {
> 	__kcrctab_unused_gpl	0 : { *(SORT(___kcrctab_unused_gpl+*)) }
> 	__kcrctab_gpl_future	0 : { *(SORT(___kcrctab_gpl_future+*)) }
>
>-	. = ALIGN(8);
>-	.init_array		0 : { *(SORT(.init_array.*)) *(.init_array) }
>+	.init_array		0 : ALIGN(8) { *(SORT(.init_array.*)) *(.init_array) }
>
> 	__jump_table		0 : ALIGN(8) { KEEP(*(__jump_table)) }
> }
>-- 
>2.9.3
>