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Date: Sat, 3 May 2025 10:27:11 -0700
From: Kees Cook <kees@kernel.org>
To: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>,
	Nicolas Schier <nicolas.schier@linux.dev>,
	Petr Pavlu <petr.pavlu@suse.com>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	linux-kbuild@vger.kernel.org, Justin Stitt <justinstitt@google.com>,
	Marco Elver <elver@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	Richard Weinberger <richard@nod.at>,
	Anton Ivanov <anton.ivanov@cambridgegreys.com>,
	Johannes Berg <johannes@sipsolutions.net>,
	linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org,
	kasan-dev@googlegroups.com, linux-um@lists.infradead.org
Subject: Re: [PATCH v2 2/3] randstruct: Force full rebuild when seed changes
Message-ID: <202505031026.6FB74507@keescook>
References: <20250502224512.it.706-kees@kernel.org>
 <20250502225416.708936-2-kees@kernel.org>
 <CAK7LNATDbxc+3HQ6zoSk9t-Lkf4MSNmEUN6S5EqoVWnBQw_K6g@mail.gmail.com>
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On Sat, May 03, 2025 at 03:13:06PM +0900, Masahiro Yamada wrote:
> On Sat, May 3, 2025 at 7:54 AM Kees Cook <kees@kernel.org> wrote:
> > +$(obj)/randstruct_hash.h $(obj)/randstruct.seed: $(gen-randstruct-seed) FORCE
> >         $(call if_changed,create_randstruct_seed)
> [...]
> So, this rule is executed twice; for randstruct_hash.h and for randstruct.seed
> 
> randstruct_hash.h and randstruct.seed will contain different hash values.
> 
> I recommend keeping the current code.

Agreed -- getting stuff into generated is much preferred. Thank you!

-- 
Kees Cook