From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752492AbdKHLIs (ORCPT ); Wed, 8 Nov 2017 06:08:48 -0500 Received: from terminus.zytor.com ([65.50.211.136]:51491 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751932AbdKHLIp (ORCPT ); Wed, 8 Nov 2017 06:08:45 -0500 Date: Wed, 8 Nov 2017 03:01:40 -0800 From: tip-bot for Ricardo Neri Message-ID: Cc: cmetcalf@mellanox.com, shuah@kernel.org, ravi.v.shankar@intel.com, hpa@zytor.com, jslaby@suse.cz, pbonzini@redhat.com, luto@kernel.org, mingo@kernel.org, tony.luck@intel.com, ray.huang@amd.com, peterz@infradead.org, vbabka@suse.cz, paul.gortmaker@windriver.com, mst@redhat.com, dvlasenk@redhat.com, mhiramat@kernel.org, corbet@lwn.net, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, torvalds@linux-foundation.org, ricardo.neri-calderon@linux.intel.com, fenghua.yu@intel.com, dave.hansen@linux.intel.com, slaoub@gmail.com, tglx@linutronix.de, brgerst@gmail.com, bp@alien8.de, bp@suse.de, jpoimboe@redhat.com Reply-To: cmetcalf@mellanox.com, hpa@zytor.com, shuah@kernel.org, jslaby@suse.cz, ravi.v.shankar@intel.com, pbonzini@redhat.com, luto@kernel.org, mingo@kernel.org, tony.luck@intel.com, ray.huang@amd.com, peterz@infradead.org, mst@redhat.com, paul.gortmaker@windriver.com, vbabka@suse.cz, dvlasenk@redhat.com, mhiramat@kernel.org, corbet@lwn.net, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, ricardo.neri-calderon@linux.intel.com, torvalds@linux-foundation.org, dave.hansen@linux.intel.com, slaoub@gmail.com, fenghua.yu@intel.com, brgerst@gmail.com, tglx@linutronix.de, bp@alien8.de, bp@suse.de, jpoimboe@redhat.com In-Reply-To: <1509935277-22138-11-git-send-email-ricardo.neri-calderon@linux.intel.com> References: <1509935277-22138-11-git-send-email-ricardo.neri-calderon@linux.intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/asm] x86/traps: Fix up general protection faults caused by UMIP Git-Commit-ID: 6fc9dc81bff0ea461db534e2672acfdaf76f3e4e X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 6fc9dc81bff0ea461db534e2672acfdaf76f3e4e Gitweb: https://git.kernel.org/tip/6fc9dc81bff0ea461db534e2672acfdaf76f3e4e Author: Ricardo Neri AuthorDate: Sun, 5 Nov 2017 18:27:55 -0800 Committer: Ingo Molnar CommitDate: Wed, 8 Nov 2017 11:16:24 +0100 x86/traps: Fix up general protection faults caused by UMIP If the User-Mode Instruction Prevention CPU feature is available and enabled, a general protection fault will be issued if the instructions sgdt, sldt, sidt, str or smsw are executed from user-mode context (CPL > 0). If the fault was caused by any of the instructions protected by UMIP, fixup_umip_exception() will emulate dummy results for these instructions as follows: in virtual-8086 and protected modes, sgdt, sidt and smsw are emulated; str and sldt are not emulated. No emulation is done for user-space long mode processes. If emulation is successful, the emulated result is passed to the user space program and no SIGSEGV signal is emitted. Signed-off-by: Ricardo Neri Reviewed-by: Thomas Gleixner Reviewed-by: Andy Lutomirski Cc: Andrew Morton Cc: Borislav Petkov Cc: Borislav Petkov Cc: Brian Gerst Cc: Chen Yucong Cc: Chris Metcalf Cc: Dave Hansen Cc: Denys Vlasenko Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Huang Rui Cc: Jiri Slaby Cc: Jonathan Corbet Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Michael S. Tsirkin Cc: Paolo Bonzini Cc: Paul Gortmaker Cc: Peter Zijlstra Cc: Ravi V. Shankar Cc: Shuah Khan Cc: Tony Luck Cc: Vlastimil Babka Cc: ricardo.neri@intel.com Link: http://lkml.kernel.org/r/1509935277-22138-11-git-send-email-ricardo.neri-calderon@linux.intel.com [ Added curly braces. ] Signed-off-by: Ingo Molnar --- arch/x86/kernel/traps.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 42a9c44..ab54bf3 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -60,6 +60,7 @@ #include #include #include +#include #ifdef CONFIG_X86_64 #include @@ -513,6 +514,11 @@ do_general_protection(struct pt_regs *regs, long error_code) RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); cond_local_irq_enable(regs); + if (static_cpu_has(X86_FEATURE_UMIP)) { + if (user_mode(regs) && fixup_umip_exception(regs)) + return; + } + if (v8086_mode(regs)) { local_irq_enable(); handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code);