From patchwork Fri Mar 20 17:59:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 11450511 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 34A4A13B1 for ; Fri, 20 Mar 2020 22:05:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E55621556 for ; Fri, 20 Mar 2020 22:05:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727671AbgCTWFI (ORCPT ); Fri, 20 Mar 2020 18:05:08 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:37507 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727426AbgCTWET (ORCPT ); Fri, 20 Mar 2020 18:04:19 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFPk1-0004TN-5N; Fri, 20 Mar 2020 23:03:45 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id 9F4A8FFC8D; Fri, 20 Mar 2020 23:03:44 +0100 (CET) Message-Id: <20200320175956.033706968@linutronix.de> User-Agent: quilt/0.65 Date: Fri, 20 Mar 2020 18:59:56 +0100 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Paul McKenney , Josh Poimboeuf , "Joel Fernandes (Google)" , "Steven Rostedt (VMware)" , Masami Hiramatsu , Alexei Starovoitov , Frederic Weisbecker , Mathieu Desnoyers , Brian Gerst , Juergen Gross , Alexandre Chartre , Peter Zijlstra , Tom Lendacky , Paolo Bonzini , kvm@vger.kernel.org Subject: [RESEND][patch V3 00/23] x86/entry: Consolidation part II (syscalls) Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi! Sorry for the resend noise. I managed to fatfinger one of my scripts so it dropped all Ccs and sent it only to LKML. Sigh.... This is the third version of the syscall entry code consolidation series. V2 can be found here: https://lore.kernel.org/r/20200308222359.370649591@linutronix.de It applies on top of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/entry and is also available from git: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel entry-v3-part2 The changes vs. V2: - A massive rework utilizing Peter Zijlstras objtool patches to analyze the new .noinstr.text section: https://lore.kernel.org/r/20200317170234.897520633@infradead.org Working with this was really helpful as it clearly pin pointed code which calls out of the protected section which is much more efficient and focussed than chasing everything manually. - Picked up the two RCU patches from Paul for completeness. The bugfix is required anyway and the comments have been really helpful to see where the defense line has to be. - As the tool flagged KVM as red zone, I looked at the context tracking usage there and it has similar if not worse issues. New set of patches dealing with that. Please have a close look at the approach and the resulting protected areas. Known issues: - The kprobes '.noinstr.text' exclusion currently works only for built in code. Haven't figured out how to to fix that, but I'm sure that Masami knows :) - The various SANitizers if enabled ruin the picture. Peter and I still have no brilliant idea what to do about that. Thanks, tglx --- arch/x86/entry/common.c | 173 ++++++++++++++++++++++++--------- arch/x86/entry/entry_32.S | 24 ---- arch/x86/entry/entry_64.S | 6 - arch/x86/entry/entry_64_compat.S | 32 ------ arch/x86/entry/thunk_64.S | 45 +++++++- arch/x86/include/asm/bug.h | 3 arch/x86/include/asm/hardirq.h | 4 arch/x86/include/asm/irqflags.h | 3 arch/x86/include/asm/nospec-branch.h | 4 arch/x86/include/asm/paravirt.h | 3 arch/x86/kvm/svm.c | 152 ++++++++++++++++++---------- arch/x86/kvm/vmx/ops.h | 4 arch/x86/kvm/vmx/vmenter.S | 2 arch/x86/kvm/vmx/vmx.c | 78 +++++++++++--- arch/x86/kvm/x86.c | 4 b/include/asm-generic/bug.h | 9 + include/asm-generic/sections.h | 3 include/asm-generic/vmlinux.lds.h | 4 include/linux/compiler.h | 24 ++++ include/linux/compiler_types.h | 4 include/linux/context_tracking.h | 27 +++-- include/linux/context_tracking_state.h | 6 - include/linux/irqflags.h | 6 + include/linux/sched.h | 1 kernel/context_tracking.c | 14 +- kernel/kprobes.c | 11 ++ kernel/locking/lockdep.c | 66 +++++++++--- kernel/panic.c | 4 kernel/rcu/tree.c | 91 +++++++++++------ kernel/rcu/tree_plugin.h | 4 kernel/rcu/update.c | 7 - kernel/trace/trace_preemptirq.c | 25 ++++ lib/debug_locks.c | 2 lib/smp_processor_id.c | 10 - scripts/mod/modpost.c | 2 35 files changed, 590 insertions(+), 267 deletions(-)