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From:   Arvind Sankar <nivedita@alum.mit.edu>
Date:   Sat, 22 Feb 2020 11:22:25 -0500
To:     Borislav Petkov <bp@alien8.de>
Cc:     Fangrui Song <maskray@google.com>,
        Nathan Chancellor <natechancellor@gmail.com>,
        Arvind Sankar <nivedita@alum.mit.edu>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com,
        Michael Matz <matz@suse.de>
Subject: Re: [PATCH 2/2] x86/boot/compressed: Remove unnecessary sections
 from bzImage
Message-ID: <20200222162225.GA3326744@rani.riverdale.lan>
References: <20200109150218.16544-1-nivedita@alum.mit.edu>
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 <20200222050845.GA19912@ubuntu-m2-xlarge-x86>
 <20200222065521.GA11284@zn.tnic>
 <20200222070218.GA27571@ubuntu-m2-xlarge-x86>
 <20200222072144.asqaxlv364s6ezbv@google.com>
 <20200222074254.GB11284@zn.tnic>
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On Sat, Feb 22, 2020 at 08:42:54AM +0100, Borislav Petkov wrote:
> On Fri, Feb 21, 2020 at 11:21:44PM -0800, Fangrui Song wrote:
> > In GNU ld, it seems that .shstrtab .symtab and .strtab are special
> > cased. Neither the input section description *(.shstrtab) nor *(*)
> > discards .shstrtab . I feel that this is a weird case (probably even a bug)
> > that lld should not implement.
> 
> Ok, forget what the tools do for a second: why is .shstrtab special and
> why would one want to keep it?
> 
> Because one still wants to know what the section names of an object are
> or other tools need it or why?
> 
> Thx.
> 
> -- 
> Regards/Gruss,
>     Boris.
> 
> https://people.kernel.org/tglx/notes-about-netiquette

.shstrtab is required by the ELF specification. The e_shstrndx field in
the ELF header is the index of .shstrtab, and each section in the
section table is required to have an sh_name that points into the
.shstrtab.