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Date: Thu, 17 Sep 2026 10:05:34 -0700
From: Kees Cook <kees@kernel.org>
To: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Nathan Chancellor <nathan@kernel.org>,
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Subject: Re: [PATCH v3 01/20] kbuild: do not allocate .modinfo in vmlinux
Message-ID: <202609171002.8C0C739@keescook>
References: <20260917-build-speedup-v3-0-9ecf4163ff36@kernel.org>
 <20260917-build-speedup-v3-1-9ecf4163ff36@kernel.org>
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In-Reply-To: <20260917-build-speedup-v3-1-9ecf4163ff36@kernel.org>

On Thu, Sep 17, 2026 at 05:06:11PM +0100, Lorenzo Stoakes (ARM) wrote:
> +      cmd_modules_builtin_modinfo = $(OBJCOPY) -O binary -j .modinfo --dump-section .modinfo=$@ $< $@.tmp; \
> +                                    rm -f $@.tmp; \
> +                                    sed -i 's/\x00\+$$/\x00/g' $@

Oh, I just noticed this. I don't think the .tmp is needed. You can just
use /dev/null for the outfile here: no need to write anything unused to
disk; seems to work for binutils and llvm's objcopy.

-- 
Kees Cook