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Peter Anvin" , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, bpf@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCH 0/4] bootconfig: embed kernel.* cmdline at build time Message-ID: References: <20260527-bootconfig_using_tools-v1-0-b6906a86e7d5@debian.org> <20260529001519.14ca9dbe92fb2622249137c6@kernel.org> Precedence: bulk X-Mailing-List: linux-kbuild@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260529001519.14ca9dbe92fb2622249137c6@kernel.org> On Fri, May 29, 2026 at 12:15:19AM +0000, Masami Hiramatsu wrote: > On Wed, 27 May 2026 09:41:33 -0700 > Breno Leitao wrote: > > > The userspace pieces (xbc_snprint_cmdline() in lib/, tools/bootconfig -C) > > already landed; this series wires the rendered cmdline into the kernel. > > > > Motivation: today the embedded bootconfig is parsed at runtime, after > > parse_early_param() has already run, so early_param() handlers can't > > see embedded values. Folding the kernel.* subtree into the cmdline at > > build time gives a CONFIG_CMDLINE-equivalent for embedded-bootconfig > > users without forcing them to maintain two cmdline sources. > > > > Behaviorally, the "kernel" subtree is rendered to a flat string at > > build time and stashed in .init.rodata. setup_arch() prepends it to > > boot_command_line before parse_early_param() runs. Overflow is a soft > > error: the helper logs and leaves boot_command_line untouched rather > > than panicking, so an oversized embedded bconf cannot brick a boot. > > > > Thanks Breno, yes, that is what I think about. > Let me check it. And could you also check Sashiko's comments? > > https://sashiko.dev/#/patchset/20260527-bootconfig_using_tools-v1-0-b6906a86e7d5%40debian.org Ack, I will have a look at them, thanks for confirming the direction is correct. --breno