From patchwork Tue Jun 2 09:05:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Roger_Pau_Monn=C3=A9?= X-Patchwork-Id: 11583401 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 02A681667 for ; Tue, 2 Jun 2020 09:06:37 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DD4D2206C3 for ; Tue, 2 Jun 2020 09:06:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DD4D2206C3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=citrix.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jg2rs-0003NQ-O2; Tue, 02 Jun 2020 09:05:56 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jg2rr-0003NK-AT for xen-devel@lists.xenproject.org; Tue, 02 Jun 2020 09:05:55 +0000 X-Inumbo-ID: 43733ab4-a4b0-11ea-81bc-bc764e2007e4 Received: from esa5.hc3370-68.iphmx.com (unknown [216.71.155.168]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 43733ab4-a4b0-11ea-81bc-bc764e2007e4; Tue, 02 Jun 2020 09:05:54 +0000 (UTC) Authentication-Results: esa5.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none IronPort-SDR: kJuVVCqWaC1yKgF0MoFq3FN+IQNKhZXJa/N49pGfOOE/yUUZ4DCgg2cf5ie6lmdLvDW5SmXl+S ggcxJv+6eAPKZPrTRRWrHAj586Godgjp+LqQzKRw1EHueIin6j0i7JRjjpP5PllP653lyHJoPX JJPpefpzpElyLvM2r74A6mKV7ftrec8Xe6NgzzZfD2bCys5wCL8kMH2kKjgEz3LXMHV+v5y8hH 9/VD+H/q56btrB9bIItjoBuTCQsZdKglxd9VoaCxytSQi7PaWrd0sciJiAHY5Vu33eohWWGjNg 32U= X-SBRS: 2.7 X-MesageID: 19253843 X-Ironport-Server: esa5.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.73,463,1583211600"; d="scan'208";a="19253843" From: Roger Pau Monne To: Subject: [PATCH for-4.14] x86/cpu: fix build with clang 3.5 Date: Tue, 2 Jun 2020 11:05:36 +0200 Message-ID: <20200602090536.38064-1-roger.pau@citrix.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Andrew Cooper , Roger Pau Monne , Wei Liu , Jan Beulich , paul@xen.org Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Clang 3.5 complains with: common.c:794:24: error: statement expression not allowed at file scope i < ARRAY_SIZE(this_cpu(tss_page).ist_ssp); ++i ) ^ /build/xen/include/asm/percpu.h:14:7: note: expanded from macro 'this_cpu' (*RELOC_HIDE(&per_cpu__##var, get_cpu_info()->per_cpu_offset)) ^ /build/xen/include/xen/compiler.h:104:3: note: expanded from macro 'RELOC_HIDE' ({ unsigned long __ptr; \ ^ /build/xen/include/xen/lib.h:68:69: note: expanded from macro 'ARRAY_SIZE' #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + __must_be_array(x)) ^ /build/xen/include/xen/compiler.h:85:57: note: expanded from macro '__must_be_array' BUILD_BUG_ON_ZERO(__builtin_types_compatible_p(typeof(a), typeof(&a[0]))) ^ /build/xen/include/xen/lib.h:39:57: note: expanded from macro 'BUILD_BUG_ON_ZERO' #define BUILD_BUG_ON_ZERO(cond) sizeof(struct { int:-!!(cond); }) ^ Workaround this by defining the tss_page as a local variable. Adjust other users of the per-cpu tss_page to also use the newly introduced local variable. No functional change expected. Signed-off-by: Roger Pau Monné Reviewed-by: Wei Liu Acked-by: Andrew Cooper --- xen/arch/x86/cpu/common.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/xen/arch/x86/cpu/common.c b/xen/arch/x86/cpu/common.c index 58f0876180..da74172776 100644 --- a/xen/arch/x86/cpu/common.c +++ b/xen/arch/x86/cpu/common.c @@ -738,9 +738,14 @@ void load_system_tables(void) unsigned int i, cpu = smp_processor_id(); unsigned long stack_bottom = get_stack_bottom(), stack_top = stack_bottom & ~(STACK_SIZE - 1); + /* + * NB: define tss_page as a local variable because clang 3.5 doesn't + * support using ARRAY_SIZE against per-cpu variables. + */ + struct tss_page *tss_page = &this_cpu(tss_page); /* The TSS may be live. Disuade any clever optimisations. */ - volatile struct tss64 *tss = &this_cpu(tss_page).tss; + volatile struct tss64 *tss = &tss_page->tss; seg_desc_t *gdt = this_cpu(gdt) - FIRST_RESERVED_GDT_ENTRY; @@ -783,15 +788,14 @@ void load_system_tables(void) * volatile qualifier. */ if (cpu_has_xen_shstk) { - volatile uint64_t *ist_ssp = this_cpu(tss_page).ist_ssp; + volatile uint64_t *ist_ssp = tss_page->ist_ssp; ist_ssp[0] = 0x8600111111111111ul; ist_ssp[IST_MCE] = stack_top + (IST_MCE * IST_SHSTK_SIZE) - 8; ist_ssp[IST_NMI] = stack_top + (IST_NMI * IST_SHSTK_SIZE) - 8; ist_ssp[IST_DB] = stack_top + (IST_DB * IST_SHSTK_SIZE) - 8; ist_ssp[IST_DF] = stack_top + (IST_DF * IST_SHSTK_SIZE) - 8; - for ( i = IST_DF + 1; - i < ARRAY_SIZE(this_cpu(tss_page).ist_ssp); ++i ) + for ( i = IST_DF + 1; i < ARRAY_SIZE(tss_page->ist_ssp); ++i ) ist_ssp[i] = 0x8600111111111111ul; wrmsrl(MSR_INTERRUPT_SSP_TABLE, (unsigned long)ist_ssp);