[CRIU] [PATCHv2 9/9] compel: Explicitely align all containers of i387_fxsave_struct

[Dmitry Safonov]

As it's aligned to 16, all structures that contain it should be
also aligned to 16. In the kernel there is no such align as
there two separate definitions of i387_fxsave_struct:
one for ia32 and another for x86_64.
Fixes newly introduced align warning in gcc-8.1:
In file included from compel/include/uapi/compel/asm/sigframe.h:7,
                 from compel/plugins/std/infect.c:13:
compel/include/uapi/compel/asm/fpu.h:89:1: error: alignment 1 of 'struct xsave_struct_ia32' is less than 16 [-Werror=packed-not-aligned]
 } __packed;
 ^

It doesn't change the current align of the struct, as containing
structures are __packed and it aligned already *by fact*.
It only affects the function users of the struct's local variables:
now they lay aligned on a stack.

Signed-off-by: Dmitry Safonov <dima at arista.com>
---
 compel/arch/x86/src/lib/include/uapi/asm/fpu.h | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/compel/arch/x86/src/lib/include/uapi/asm/fpu.h b/compel/arch/x86/src/lib/include/uapi/asm/fpu.h
index f60112b9ba50..dca280bdb61d 100644
--- a/compel/arch/x86/src/lib/include/uapi/asm/fpu.h
+++ b/compel/arch/x86/src/lib/include/uapi/asm/fpu.h
@@ -8,6 +8,7 @@
 #include <compel/common/compiler.h>
 
 #define FP_MIN_ALIGN_BYTES		64
+#define FXSAVE_ALIGN_BYTES		16
 
 #define FP_XSTATE_MAGIC1		0x46505853U
 #define FP_XSTATE_MAGIC2		0x46505845U
@@ -61,7 +62,7 @@ struct i387_fxsave_struct {
 		uint32_t		sw_reserved[12];
 	};
 
-} __aligned(16);
+} __aligned(FXSAVE_ALIGN_BYTES);
 
 struct xsave_hdr_struct {
 	uint64_t			xstate_bv;
@@ -86,7 +87,7 @@ struct xsave_struct_ia32 {
 	struct i387_fxsave_struct	i387;
 	struct xsave_hdr_struct		xsave_hdr;
 	struct ymmh_struct		ymmh;
-} __packed;
+} __aligned(FXSAVE_ALIGN_BYTES) __packed;
 
 typedef struct {
 	/*
@@ -123,8 +124,8 @@ typedef struct {
 	union {
 		struct xsave_struct_ia32	xsave;
 		uint8_t				__pad[sizeof(struct xsave_struct) + FP_XSTATE_MAGIC2_SIZE];
-	} __packed;
-}  __packed fpu_state_ia32_t;
+	} __aligned(FXSAVE_ALIGN_BYTES) __packed;
+} __aligned(FXSAVE_ALIGN_BYTES) __packed fpu_state_ia32_t;
 
 /*
  * This one is used in restorer.
-- 
2.13.6