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Date:   Wed, 23 Nov 2022 09:45:37 -0800
From:   "H. Peter Anvin" <hpa@zytor.com>
To:     Borislav Petkov <bp@alien8.de>, Petr Pavlu <petr.pavlu@suse.com>
CC:     tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com,
        x86@kernel.org, nicolas@fjasle.eu, masahiroy@kernel.org,
        kirill.shutemov@linux.intel.com, tony.luck@intel.com,
        michael.roth@amd.com, nathan@kernel.org, ndesaulniers@google.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] x86: Avoid relocation information in final vmlinux
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On November 23, 2022 7:54:29 AM PST, Borislav Petkov <bp@alien8=2Ede> wrote=
:
>On Wed, Nov 23, 2022 at 04:43:20PM +0100, Petr Pavlu wrote:
>> The only post-link analysis tool in this case should be arch/x86/tools/=
relocs=2E
>> It produces a vmlinux=2Erelocs file which is appended to vmlinux=2Ebin=
=2E This is
>> all internal to the Linux build=2E I'm not aware of any external toolin=
g, such
>> as kernel debuggers, that would require this relocation information in
>> vmlinux=2E
>
>It would be good to know why --emit-relocs was added in the first place
>- that might give us a hint=2E Lemme talk to Micha=2E
>
>> The size command used in your example includes only allocatable code, d=
ata and
>> bss sections=2E It does not show size of any relocation sections=2E
>
>This:
>
>361M vmlinux=2Ebefore
>361M vmlinux=2Eafter
>
>is simple ls output=2E
>
>Maybe I need something else enabled in my =2Econfig which would show this
>significant difference *and* *explain* it=2E
>
>Thx=2E
>

The real question is: why does anyone care about the size of the vmlinux f=
ile specifically?