From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH V38 15/29] acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down Date: Wed, 14 Aug 2019 19:47:32 +0200 Message-ID: <20190814174732.GD1841@zn.tnic> References: <20190808000721.124691-1-matthewgarrett@google.com> <20190808000721.124691-16-matthewgarrett@google.com> <20190814072602.GA27836@zn.tnic> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Matthew Garrett Cc: James Morris , LSM List , Linux Kernel Mailing List , Linux API , Josh Boyer , David Howells , Kees Cook , Dave Young , linux-acpi@vger.kernel.org List-Id: linux-api@vger.kernel.org On Wed, Aug 14, 2019 at 10:14:54AM -0700, Matthew Garrett wrote: > We explicitly don't want to pay attention to the acpi_rsdp kernel > parameter in early boot except for the case of finding the SRAT table, > and we only need that if CONFIG_RANDOMIZE_BASE and > CONFIG_MEMORY_HOTREMOVE are set. However, we *do* want to tell the > actual kernel where the RSDP is if we found it via some other means, > so we can't just clear the boot parameters value. Ok. > The kernel proper will parse the command line again and will then (if > lockdown isn't enabled) override the actual value we passed up in boot > params. Yeah, ok, I see what you're doing there. AFAICT, you do that in setup_arch->acpi_boot_table_init-> ... -> acpi_os_get_root_pointer() I hope nothing needs it earlier because then we'll have to restructure again... Thx. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.