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dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=h0co268DQdDsFIpkHG0hlwzQMNMCkE0qS/pEaHpK32U=; b=Lt/RTO5f32YBWnjfuIKP4Sz2DA 1yUjNwgz93yzZ3B4ciEQNJTD49MueTqwh79hSRqjfT5bRb8exdWcureaRCrWHGtGjUV/QdXWLRrro P09bYKP9g3hwQLSVerCF1W6Uyjrdc+fKavSNviG2HWVcNI1OAH+QI45dVkCdBuHSKcNzaQhaVtMiC wWy1JEjjZKfbceo1UZhawRz2FoCMsU06yn1jLxY+P3vP/pT9JUV0QKh9JKLNrvE2mAbUpYX5ug5IM JqwZ6o38XEQDMVqYlppXUii7rmcbgJDudZNs7/zXyMSIJxcs5efO1bV5J+EckMpWL8wf75buR06L1 2izPNXxA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jHVrk-0005bw-Qi; Thu, 26 Mar 2020 17:00:24 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jHVrI-00048q-Cb for linux-arm-kernel@lists.infradead.org; Thu, 26 Mar 2020 16:59:57 +0000 Received: from e123331-lin.home (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C249A2076A; Thu, 26 Mar 2020 16:59:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585241996; bh=WOxWjfDmGgg1+ZblWxXKQ7OejY4FNXMxB6c3NNDo23Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a5yS6UI+qIXaocfR3tO4kOzpDdfzRknly4fV8lN/Y+PTW38wpngB7+Kd9aHPD6wNf zpF/TOJg8TJ+YEla3iNTKBnNBcoPVTdzIDMrpikCjVr43EkanYnwZv+9HdSQPySgxF QtlG8IXCFTTfpDnQ48/jz68+2S8GYYvxaPl0dkHk= From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 1/2] efi/libstub/arm64: avoid copying the kernel unnecessarily Date: Thu, 26 Mar 2020 17:59:04 +0100 Message-Id: <20200326165905.2240-2-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326165905.2240-1-ardb@kernel.org> References: <20200326165905.2240-1-ardb@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200326_095956_452451_CC8E1831 X-CRM114-Status: GOOD ( 10.06 ) X-Spam-Score: -5.2 (-----) X-Spam-Report: SpamAssassin version 3.4.4 on bombadil.infradead.org summary: Content analysis details: (-5.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.0 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, catalin.marinas@arm.com, linux-efi@vger.kernel.org, will@kernel.org, Ard Biesheuvel MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org If the UEFI firmware has loaded the kernel at the right alignment, and we are running a relocatable kernel, there is no point in copying the kernel to a different place in memory, and instead, we can just run it in place. Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/arm64-stub.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c index 9254cd8ab2d3..d263f504dcf0 100644 --- a/drivers/firmware/efi/libstub/arm64-stub.c +++ b/drivers/firmware/efi/libstub/arm64-stub.c @@ -104,6 +104,15 @@ efi_status_t handle_kernel_image(unsigned long *image_addr, (u32)phys_seed); *image_addr = *reserve_addr + offset; + } else if (IS_ENABLED(CONFIG_RELOCATABLE) && + IS_ALIGNED((u64)_text - TEXT_OFFSET, EFI_KIMG_ALIGN)) { + /* + * If we are relocatable and were loaded at a suitable offset, + * there is no need to do anything and we can just execute in + * place. + */ + *image_addr = (u64)_text; + return EFI_SUCCESS; } else { /* * Else, try a straight allocation at the preferred offset.