Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932685AbbDOXco (ORCPT ); Wed, 15 Apr 2015 19:32:44 -0400 Received: from mail-ie0-f181.google.com ([209.85.223.181]:36827 "EHLO mail-ie0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752154AbbDOXcg (ORCPT ); Wed, 15 Apr 2015 19:32:36 -0400 From: Roy Franz To: linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, matt.fleming@intel.com, hpa@zytor.com, mingo@redhat.com, x86@kernel.org Cc: Roy Franz Subject: [PATCH] x86/efi: Store upper bits of command line buffer address in ext_cmd_line_ptr Date: Wed, 15 Apr 2015 16:32:24 -0700 Message-Id: <1429140744-25768-1-git-send-email-roy.franz@linaro.org> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1664 Lines: 39 Until now, the EFI stub was only setting the 32 bit cmd_line_ptr in the setup_header structure, so on 64 bit platforms this could be truncated. This patch adds setting the upper bits of the buffer address in ext_cmd_line_ptr. This case was likely never hit, as the allocation for this buffer is done at the lowest available address. Only x86_64 kernels have this problem, as the 1-1 mapping mandated by EFI ensures that all memory is 32 bit addressable on 32 bit platforms. The EFI stub does not support mixed mode, so the 32 bit kernel on 64 bit firmware case does not need to be handled. Signed-off-by: Roy Franz --- This is a follow-up to "x86_64/efi: enforce 32 bit address for command line buffer", which had the wrong fix to the truncation of address. arch/x86/boot/compressed/eboot.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index ef17683..48304b8 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1109,6 +1109,8 @@ struct boot_params *make_boot_params(struct efi_config *c) if (!cmdline_ptr) goto fail; hdr->cmd_line_ptr = (unsigned long)cmdline_ptr; + /* Fill in upper bits of command line address, NOP on 32 bit */ + boot_params->ext_cmd_line_ptr = (u64)(unsigned long)cmdline_ptr >> 32; hdr->ramdisk_image = 0; hdr->ramdisk_size = 0; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/