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elfnote: place note in a PT_NOTE program header

Description

elfnote: place note in a PT_NOTE program header

Some tools (firecraker loader) only check for notes in PT_NOTE program
headers, so make sure the notes added using the ELFNOTE macro end up
in such header.

Output from readelf -Wl for and amd64 kernel after the change:

Elf file type is EXEC (Executable file)
Entry point 0xffffffff8038a000
There are 11 program headers, starting at offset 64

Program Headers:

Type           Offset   VirtAddr           PhysAddr           FileSiz  MemSiz   Flg Align
PHDR           0x000040 0xffffffff80200040 0x0000000000200040 0x000268 0x000268 R   0x8
INTERP         0x0002a8 0xffffffff802002a8 0x00000000002002a8 0x00000d 0x00000d R   0x1
    [Requesting program interpreter: /red/herring]
LOAD           0x000000 0xffffffff80200000 0x0000000000200000 0x189e28 0x189e28 R   0x200000
LOAD           0x18a000 0xffffffff8038a000 0x000000000038a000 0xe447e8 0xe447e8 R E 0x200000
LOAD           0xfce7f0 0xffffffff811ce7f0 0x00000000011ce7f0 0x6b955c 0x6b955c R   0x200000
LOAD           0x1800000 0xffffffff81a00000 0x0000000001a00000 0x000140 0x000140 RW  0x200000
LOAD           0x1801000 0xffffffff81a01000 0x0000000001a01000 0x1c8480 0x5ff000 RW  0x200000
DYNAMIC        0x1800000 0xffffffff81a00000 0x0000000001a00000 0x000140 0x000140 RW  0x8
GNU_RELRO      0x1800000 0xffffffff81a00000 0x0000000001a00000 0x000140 0x000140 R   0x1
GNU_STACK      0x000000 0x0000000000000000 0x0000000000000000 0x000000 0x000000 RW  0
NOTE           0x1687ae0 0xffffffff81887ae0 0x0000000001887ae0 0x0001c0 0x0001c0 R   0x4

Section to Segment mapping:

Segment Sections...

[...]

10     .note.gnu.build-id .note.Xen

Reported by: cperciva
Fixes: 1a9cdd373a6a ('xen: add PV/PVH kernel entry point')
Fixes: 93ee134a24fa ('Integrate support for xen in to i386 common code.')
Sponsored by: Citrix Systems R&D
Reviewed by: emaste
Differential revision: https://reviews.freebsd.org/D35611

Details

Provenance
roygerAuthored on Jun 27 2022, 1:51 PM
Reviewer
emaste
Differential Revision
D35611: elfnote: place note in a PT_NOTE program header
Parents
rG091febc04a5d: xen/blkback: do not use x86 CPUID in generic code
Branches
Unknown
Tags
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