From: Johan Hovold Date: Mon, 23 Nov 2020 10:23:16 +0000 (+0100) Subject: init: use type alignment for kernel parameters X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=147ad605dc12c515c97136899ccb5c70e6c674e1;p=linux.git init: use type alignment for kernel parameters Specify type alignment for kernel parameters instead of sizeof(long). The alignment attribute is used to prevent gcc from increasing the alignment of objects with static extent as an optimisation, something which would mess up the __setup array stride. Using __alignof__(struct obs_kernel_param) rather than sizeof(long) is preferred since it better indicates why it is there and doesn't break should the type size or alignment change. Note that on m68k the alignment of struct obs_kernel_param is actually two and that adding a 1- or 2-byte field to the 12-byte struct would cause a breakage with the current 4-byte alignment. Link: https://lore.kernel.org/lkml/20201103175711.10731-1-johan@kernel.org Signed-off-by: Johan Hovold Signed-off-by: Jessica Yu --- diff --git a/include/linux/init.h b/include/linux/init.h index 7b53cb3092ee9..e668832ef66ad 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -255,7 +255,7 @@ struct obs_kernel_param { __aligned(1) = str; \ static struct obs_kernel_param __setup_##unique_id \ __used __section(".init.setup") \ - __attribute__((aligned((sizeof(long))))) \ + __aligned(__alignof__(struct obs_kernel_param)) \ = { __setup_str_##unique_id, fn, early } #define __setup(str, fn) \