From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752757AbdDMKOB (ORCPT ); Thu, 13 Apr 2017 06:14:01 -0400 Received: from mx2.suse.de ([195.135.220.15]:49917 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756629AbdDMKLm (ORCPT ); Thu, 13 Apr 2017 06:11:42 -0400 From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com, Juergen Gross Subject: [PATCH v2 07/11] x86/xen: use capabilities instead of fake cpuid values for mwait Date: Thu, 13 Apr 2017 12:11:12 +0200 Message-Id: <20170413101116.723-8-jgross@suse.com> X-Mailer: git-send-email 2.12.0 In-Reply-To: <20170413101116.723-1-jgross@suse.com> References: <20170413101116.723-1-jgross@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When running as pv domain xen_cpuid() is being used instead of native_cpuid(). In xen_cpuid() the mwait feature is indicated to be present or not by special casing the related cpuid leaf. Instead of delivering fake cpuid values use the cpu capability bit for mwait instead. Signed-off-by: Juergen Gross --- arch/x86/xen/enlighten_pv.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 3196961862bc..d43382284ada 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -167,7 +167,6 @@ xen_running_on_version_or_later(unsigned int major, unsigned int minor) static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0; -static __read_mostly unsigned int cpuid_leaf1_ecx_set_mask; static __read_mostly unsigned int cpuid_leaf5_ecx_val; static __read_mostly unsigned int cpuid_leaf5_edx_val; @@ -176,7 +175,6 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, { unsigned maskebx = ~0; unsigned maskecx = ~0; - unsigned setecx = 0; /* * Mask out inconvenient features, to try and disable as many * unsupported kernel subsystems as possible. @@ -184,7 +182,6 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, switch (*ax) { case 1: maskecx = cpuid_leaf1_ecx_mask; - setecx = cpuid_leaf1_ecx_set_mask; break; case CPUID_MWAIT_LEAF: @@ -210,7 +207,6 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, *bx &= maskebx; *cx &= maskecx; - *cx |= setecx; } STACK_FRAME_NON_STANDARD(xen_cpuid); /* XEN_EMULATE_PREFIX */ @@ -303,8 +299,6 @@ static void __init xen_init_cpuid_mask(void) /* Xen will set CR4.OSXSAVE if supported and not disabled by force */ if ((cx & xsave_mask) != xsave_mask) cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */ - if (xen_check_mwait()) - cpuid_leaf1_ecx_set_mask = (1 << (X86_FEATURE_MWAIT % 32)); } static void __init xen_init_capabilities(void) @@ -318,6 +312,11 @@ static void __init xen_init_capabilities(void) if (!xen_initial_domain()) setup_clear_cpu_cap(X86_FEATURE_ACPI); + + if (xen_check_mwait()) + setup_force_cpu_cap(X86_FEATURE_MWAIT); + else + setup_clear_cpu_cap(X86_FEATURE_MWAIT); } static void xen_set_debugreg(int reg, unsigned long val) -- 2.12.0