From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751652AbaGLVK5 (ORCPT ); Sat, 12 Jul 2014 17:10:57 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:37371 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750892AbaGLVKj (ORCPT ); Sat, 12 Jul 2014 17:10:39 -0400 From: Daniel Kiper To: linux-kernel@vger.kernel.org, x86@kernel.org, xen-devel@lists.xenproject.org Cc: andrew.cooper3@citrix.com, boris.ostrovsky@oracle.com, david.vrabel@citrix.com, hpa@zytor.com, ian.campbell@citrix.com, jbeulich@suse.com, jeremy@goop.org, konrad.wilk@oracle.com, matt.fleming@intel.com, mingo@redhat.com, stefano.stabellini@eu.citrix.com, tglx@linutronix.de Subject: [PATCH v2 2/2] arch/x86/xen: Silence compiler warnings Date: Sat, 12 Jul 2014 23:09:48 +0200 Message-Id: <1405199388-5692-3-git-send-email-daniel.kiper@oracle.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1405199388-5692-1-git-send-email-daniel.kiper@oracle.com> References: <1405199388-5692-1-git-send-email-daniel.kiper@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Compiler complains in the following way when x86 32-bit kernel with Xen support is build: CC arch/x86/xen/enlighten.o arch/x86/xen/enlighten.c: In function ‘xen_start_kernel’: arch/x86/xen/enlighten.c:1726:3: warning: right shift count >= width of type [enabled by default] Such line contains following EFI initialization code: boot_params.efi_info.efi_systab_hi = (__u32)(__pa(efi_systab_xen) >> 32); There is no issue if x86 64-bit kernel is build. However, 32-bit case generate warning (even if that code will not be executed because Xen does not work on 32-bit EFI platforms) due to __pa() returning unsigned long type which has 32-bits width. So move whole EFI initialization stuff to separate function and build it conditionally to avoid above mentioned warning on x86 32-bit architecture. Signed-off-by: Daniel Kiper --- v2 - suggestions/fixes: - move xen_efi_init() to separate module (suggested by Konrad Rzeszutek Wilk). --- arch/x86/xen/Makefile | 1 + arch/x86/xen/efi.c | 43 +++++++++++++++++++++++++++++++++++++++++++ arch/x86/xen/enlighten.c | 15 +-------------- arch/x86/xen/xen-ops.h | 8 ++++++++ 4 files changed, 53 insertions(+), 14 deletions(-) create mode 100644 arch/x86/xen/efi.c diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile index 96ab2c0..7322755 100644 --- a/arch/x86/xen/Makefile +++ b/arch/x86/xen/Makefile @@ -22,3 +22,4 @@ obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= spinlock.o obj-$(CONFIG_XEN_DEBUG_FS) += debugfs.o obj-$(CONFIG_XEN_DOM0) += apic.o vga.o obj-$(CONFIG_SWIOTLB_XEN) += pci-swiotlb-xen.o +obj-$(CONFIG_XEN_EFI) += efi.o diff --git a/arch/x86/xen/efi.c b/arch/x86/xen/efi.c new file mode 100644 index 0000000..a02e09e --- /dev/null +++ b/arch/x86/xen/efi.c @@ -0,0 +1,43 @@ +/* + * Copyright (c) 2014 Oracle Co., Daniel Kiper + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program. If not, see . + */ + +#include +#include +#include + +#include + +#include + +void __init xen_efi_init(void) +{ + efi_system_table_t *efi_systab_xen; + + efi_systab_xen = xen_efi_probe(); + + if (efi_systab_xen == NULL) + return; + + strncpy((char *)&boot_params.efi_info.efi_loader_signature, "Xen", + sizeof(boot_params.efi_info.efi_loader_signature)); + boot_params.efi_info.efi_systab = (__u32)__pa(efi_systab_xen); + boot_params.efi_info.efi_systab_hi = (__u32)(__pa(efi_systab_xen) >> 32); + + set_bit(EFI_BOOT, &efi.flags); + set_bit(EFI_PARAVIRT, &efi.flags); + set_bit(EFI_64BIT, &efi.flags); +} diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index bc89647..2cd0463 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -32,7 +32,6 @@ #include #include #include -#include #include #include @@ -1521,7 +1520,6 @@ asmlinkage __visible void __init xen_start_kernel(void) { struct physdev_set_iopl set_iopl; int rc; - efi_system_table_t *efi_systab_xen; if (!xen_start_info) return; @@ -1717,18 +1715,7 @@ asmlinkage __visible void __init xen_start_kernel(void) xen_setup_runstate_info(0); - efi_systab_xen = xen_efi_probe(); - - if (efi_systab_xen) { - strncpy((char *)&boot_params.efi_info.efi_loader_signature, "Xen", - sizeof(boot_params.efi_info.efi_loader_signature)); - boot_params.efi_info.efi_systab = (__u32)__pa(efi_systab_xen); - boot_params.efi_info.efi_systab_hi = (__u32)(__pa(efi_systab_xen) >> 32); - - set_bit(EFI_BOOT, &efi.flags); - set_bit(EFI_PARAVIRT, &efi.flags); - set_bit(EFI_64BIT, &efi.flags); - } + xen_efi_init(); /* Start the world */ #ifdef CONFIG_X86_32 diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index c834d4b..75f98fe 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -104,6 +104,14 @@ static inline void __init xen_init_apic(void) } #endif +#ifdef CONFIG_XEN_EFI +extern void xen_efi_init(void); +#else +static inline void __init xen_efi_init(void) +{ +} +#endif + /* Declare an asm function, along with symbols needed to make it inlineable */ #define DECL_ASM(ret, name, ...) \ -- 1.7.10.4