Re: [PATCH v3 1/1] x86/elf: Add a new .note section containing xfeatures buffer layout info to x86 core files

From: Balasubrmanian, Vignesh
Date: Wed Jul 17 2024 - 05:32:46 EST



On 7/13/2024 4:12 PM, Thomas Gleixner wrote:
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On Fri, Jul 12 2024 at 15:16, Vignesh Balasubramanian wrote:
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index 1fb83d477..cad37090b 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -13,6 +13,15 @@
#include <asm/auxvec.h>
#include <asm/fsgsbase.h>

+struct xfeat_component {
+ u32 type;
+ u32 size;
+ u32 offset;
+ u32 flags;
+} __packed;
+
+_Static_assert(sizeof(struct xfeat_component)%4 == 0, "xfeat_component is not aligned");
This struct is only used in xstate.c and asm/elf.h is not a UAPI
header. So what's the point of declaring it in the header instead of
xtsate.c?

If this needs to provided for user space consumption, then it want's to
be in a UAPI header, no?
Our initial idea is to pass the "struct xfeat_component" through "glibc".
is "include/uapi/linux/elf.h" proper header to add this ?

I couldn't see any proper header inside "arch/x86/include/uapi/asm/".

Please advise.


thanks,
vigneshbalu
Thanks,

tglx