From patchwork Fri Feb 5 13:42:01 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Cooper X-Patchwork-Id: 8234461 Return-Path: X-Original-To: patchwork-xen-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 0781A9F6DA for ; Fri, 5 Feb 2016 13:45:09 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 03B2920115 for ; Fri, 5 Feb 2016 13:45:08 +0000 (UTC) Received: from lists.xen.org (lists.xenproject.org [50.57.142.19]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F0B7320389 for ; Fri, 5 Feb 2016 13:45:06 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aRgee-0006j8-OS; Fri, 05 Feb 2016 13:42:32 +0000 Received: from mail6.bemta4.messagelabs.com ([85.158.143.247]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aRgec-0006hX-JR for xen-devel@lists.xen.org; Fri, 05 Feb 2016 13:42:30 +0000 Received: from [85.158.143.35] by server-3.bemta-4.messagelabs.com id 69/AB-31122-6C6A4B65; Fri, 05 Feb 2016 13:42:30 +0000 X-Env-Sender: prvs=8364524b4=Andrew.Cooper3@citrix.com X-Msg-Ref: server-16.tower-21.messagelabs.com!1454679747!9808982!3 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 7.35.1; banners=-,-,- X-VirusChecked: Checked Received: (qmail 61764 invoked from network); 5 Feb 2016 13:42:29 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-16.tower-21.messagelabs.com with RC4-SHA encrypted SMTP; 5 Feb 2016 13:42:29 -0000 X-IronPort-AV: E=Sophos;i="5.22,400,1449532800"; d="scan'208";a="329916716" From: Andrew Cooper To: Xen-devel Date: Fri, 5 Feb 2016 13:42:01 +0000 Message-ID: <1454679743-18133-9-git-send-email-andrew.cooper3@citrix.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1454679743-18133-1-git-send-email-andrew.cooper3@citrix.com> References: <1454679743-18133-1-git-send-email-andrew.cooper3@citrix.com> MIME-Version: 1.0 X-DLP: MIA2 Cc: Andrew Cooper , Jan Beulich Subject: [Xen-devel] [PATCH v2 08/30] xen/x86: Mask out unknown features from Xen's capabilities X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If Xen doesn't know about a feature, it is unsafe for use and should be deliberately hidden from Xen's capabilities. This doesn't make a practical difference yet, but will make a difference later when the guest featuresets are seeded from the host featureset. Signed-off-by: Andrew Cooper Acked-by: Jan Beulich --- CC: Jan Beulich v2: * Reduced substantially from v1, by using the autogenerated information. --- xen/arch/x86/Makefile | 1 + xen/arch/x86/cpu/common.c | 3 +++ xen/arch/x86/cpuid.c | 19 +++++++++++++++++++ xen/include/asm-x86/cpufeature.h | 3 +-- xen/include/asm-x86/cpuid.h | 24 ++++++++++++++++++++++++ xen/tools/gen-cpuid.py | 24 ++++++++++++++++++++++++ 6 files changed, 72 insertions(+), 2 deletions(-) create mode 100644 xen/arch/x86/cpuid.c create mode 100644 xen/include/asm-x86/cpuid.h diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile index 8e6e901..0e2b1d5 100644 --- a/xen/arch/x86/Makefile +++ b/xen/arch/x86/Makefile @@ -12,6 +12,7 @@ obj-y += bitops.o obj-bin-y += bzimage.init.o obj-bin-y += clear_page.o obj-bin-y += copy_page.o +obj-y += cpuid.o obj-y += compat.o x86_64/compat.o obj-$(CONFIG_KEXEC) += crash.o obj-y += debug.o diff --git a/xen/arch/x86/cpu/common.c b/xen/arch/x86/cpu/common.c index a99cc7c..151dfe4 100644 --- a/xen/arch/x86/cpu/common.c +++ b/xen/arch/x86/cpu/common.c @@ -341,6 +341,9 @@ void identify_cpu(struct cpuinfo_x86 *c) * The vendor-specific functions might have changed features. Now * we do "generic changes." */ + for (i = 0; i < FSCAPINTS; ++i) { + c->x86_capability[i] &= known_features[i]; + } for (i = 0 ; i < NCAPINTS ; ++i) c->x86_capability[i] &= ~cleared_caps[i]; diff --git a/xen/arch/x86/cpuid.c b/xen/arch/x86/cpuid.c new file mode 100644 index 0000000..fb3a6ac --- /dev/null +++ b/xen/arch/x86/cpuid.c @@ -0,0 +1,19 @@ +#include +#include + +const uint32_t known_features[] = INIT_KNOWN_FEATURES; + +static void __maybe_unused build_assertions(void) +{ + BUILD_BUG_ON(ARRAY_SIZE(known_features) != FSCAPINTS); +} + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * tab-width: 4 + * indent-tabs-mode: nil + * End: + */ diff --git a/xen/include/asm-x86/cpufeature.h b/xen/include/asm-x86/cpufeature.h index d069563..a984a81 100644 --- a/xen/include/asm-x86/cpufeature.h +++ b/xen/include/asm-x86/cpufeature.h @@ -13,9 +13,8 @@ #include -#include +#include -#define FSCAPINTS FEATURESET_NR_ENTRIES #define NCAPINTS (FSCAPINTS + 1) /* N 32-bit words worth of info */ /* Other features, Linux-defined mapping, FSMAX+1 */ diff --git a/xen/include/asm-x86/cpuid.h b/xen/include/asm-x86/cpuid.h new file mode 100644 index 0000000..6cca5ea --- /dev/null +++ b/xen/include/asm-x86/cpuid.h @@ -0,0 +1,24 @@ +#ifndef __X86_CPUID_H__ +#define __X86_CPUID_H__ + +#include + +#define FSCAPINTS FEATURESET_NR_ENTRIES + +#ifndef __ASSEMBLY__ +#include + +extern const uint32_t known_features[FSCAPINTS]; + +#endif /* __ASSEMBLY__ */ +#endif /* !__X86_CPUID_H__ */ + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * tab-width: 4 + * indent-tabs-mode: nil + * End: + */ diff --git a/xen/tools/gen-cpuid.py b/xen/tools/gen-cpuid.py index c8240c0..0843be6 100755 --- a/xen/tools/gen-cpuid.py +++ b/xen/tools/gen-cpuid.py @@ -19,6 +19,8 @@ class State(object): # State calculated self.nr_entries = 0 # Number of words in a featureset + self.common = 0 # Common features between 1d and e1d + self.known = [] # All known features def parse_definitions(state): """ @@ -89,6 +91,22 @@ def crunch_numbers(state): # Size of bitmaps state.nr_entries = nr_entries = (max(state.names.keys()) >> 5) + 1 + # Features common between 1d and e1d. + common_1d = (FPU, VME, DE, PSE, TSC, MSR, PAE, MCE, CX8, APIC, + MTRR, PGE, MCA, CMOV, PAT, PSE36, MMX, FXSR) + + # All known features. Duplicate the common features in e1d + e1d_base = (SYSCALL >> 5) << 5 + state.known = featureset_to_uint32s( + state.names.keys() + [ e1d_base + (x % 32) for x in common_1d ], + nr_entries) + + # Fold common back into names + for f in common_1d: + state.names[e1d_base + (f % 32)] = "E1D_" + state.names[f] + + state.common = featureset_to_uint32s(common_1d, 1)[0] + def write_results(state): state.output.write( @@ -103,7 +121,13 @@ def write_results(state): state.output.write( """ #define FEATURESET_NR_ENTRIES %s + +#define INIT_COMMON_FEATURES %s + +#define INIT_KNOWN_FEATURES { \\\n%s\n} """ % (state.nr_entries, + state.common, + format_uint32s(state.known, 4), )) state.output.write(