diff options
| author | Johan Hovold <johan@kernel.org> | 2020-11-23 11:23:18 +0100 |
|---|---|---|
| committer | Jessica Yu <jeyu@kernel.org> | 2020-11-25 15:45:03 +0100 |
| commit | fe2f4fe139b321a38daafc715aeb7d21d9e8e5ad (patch) | |
| tree | e5face2f34980a240b4e9413009086ae223e8c63 | |
| parent | 8d6615f1fccc4f39d7d3dcf286b33e8a1e833d2b (diff) | |
params: use type alignment for kernel parameters
Specify type alignment for kernel parameters instead of sizeof(void *).
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 __param array stride.
Using __alignof__(struct kernel_param) rather than sizeof(void *) 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 kernel_param is actually two
and that adding a 1- or 2-byte field to the 20-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 <johan@kernel.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
| -rw-r--r-- | include/linux/moduleparam.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index 742074ad9f6e..15ecc6cc3a3b 100644 --- a/include/linux/moduleparam.h +++ b/include/linux/moduleparam.h @@ -288,8 +288,8 @@ struct kparam_array /* Default value instead of permissions? */ \ static const char __param_str_##name[] = prefix #name; \ static struct kernel_param __moduleparam_const __param_##name \ - __used \ - __section("__param") __attribute__ ((aligned(sizeof(void *)))) \ + __used __section("__param") \ + __aligned(__alignof__(struct kernel_param)) \ = { __param_str_##name, THIS_MODULE, ops, \ VERIFY_OCTAL_PERMISSIONS(perm), level, flags, { arg } } |