From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 112BFEE49A6 for ; Mon, 21 Aug 2023 11:27:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232327AbjHUL1i (ORCPT ); Mon, 21 Aug 2023 07:27:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232252AbjHUL1d (ORCPT ); Mon, 21 Aug 2023 07:27:33 -0400 Received: from esa3.hc3370-68.iphmx.com (esa3.hc3370-68.iphmx.com [216.71.145.155]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C939C3 for ; Mon, 21 Aug 2023 04:27:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1692617251; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=+GjJMJBMnIjNb7IoAj9YQgAPR3WDw+7KrmPdjN04OSU=; b=XbXvcC7Iowb8/IRiyP5p2McMBWG7gZLgIkEsrog07b8SqOnWdWCVdizj YhPp3BDsAHZye1x4eoDSfeTnbuq0HzHDK4o8CULtW1eAhqeZgmCcHS0U2 oEfqZh90+i/272LO2hpv+2tstK726Nb+hkBlyaVhgZkb/RbdAByyc88x+ g=; Authentication-Results: esa3.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none X-SBRS: 4.0 X-MesageID: 120127124 X-Ironport-Server: esa3.hc3370-68.iphmx.com X-Remote-IP: 162.221.156.123 X-Policy: $RELAYED IronPort-Data: A9a23:vDiPLqnUr5A85LKB/mRw22no5gwoJkRdPkR7XQ2eYbSJt1+Wr1Gzt xIbXjzQbq6IN2H1fNEnPYu1oB8Gv8SHnNY1SVdrrSxgFSMWpZLJC+rCIxarNUt+DCFhoGFPt JxCN4aafKjYaleG+39B55C49SEUOZmgH+a6U6icfHgqH2eIcQ954Tp7gek1n4V0ttawBgKJq LvartbWfVSowFaYCEpNg064gE0p5K2aVA8w5ARkPqgb5gaGzRH5MbpETU2PByqgKmVrNrbSq 9brlNmR4m7f9hExPdKp+p6TnpoiG+O60aCm0xK6aoD66vRwjnVaPpUTbZLwXXx/mTSR9+2d/ f0W3XCGpaXFCYWX8AgVe0Ew/yiTpsSq8pefSZS0mZT7I0Er7xIAahihZa07FdRwxwp5PY1B3 eEVKTI3RR6Ku/mdn/G2QMh8oMoRMMa+aevzulk4pd3YJfMvQJSFSKTW/95Imjw3g6iiH96HO ZBfM2A2Kk2dPVsWYAx/5JEWxY9EglHWdTFCpU3Tjq0w+2XJlyR60aT3McqTcduPLSlQth/C/ jucoD2jXnn2MvTA9BSgyE/9h9SMgDGqYd8ICpqk3OB11Qj7Kms7V0RNCArTTeOCokq/Xc9Pb k8Z4CwjqYAs+0GxCNrwRRu1pDiDpBF0c9BIO+Q+6QyLmuzY7m6xHmUYQyRTQN0gutU/STEj2 hmOhdyBLSw/7pWWRGib+7PSqim9UQAXNWgDYCUDQCMG7sPlrYV1iQjAJv5pGaSoyNjyFjzq6 zmPoG41gLB7peICyaS3u3POmzaloLDASwJz7QLSNkqj7wA/bom/Zpev93DA8O1Nao2eSzGps 2IJlMuexOQPC4ydmiuQRukEALCu4bCCKjK0qUJgG4kJ8zWr5mK5eoZR8HdyKS9U3t0sIGGzJ hWJ4EUIucEVZSHxBUNqX26vI9knzKraPtrsauv/MZlDaLlhUgG14C47MCZ8wFvRuEQrlKg+P 7KSfsCtEWsWBMxb8damewsO+eR1n35jnAs/Ubi+lk36iuTGOBZ5XJ9faDOzgvYFALRoSek/2 /JWLIO0xhpWS4USiQGHoNdIfTjmwZXWbK0aSvC7lMbYe2KK+0l7UZc9JI/NnKQ8xMxoeh/gp C3VZ6Oh4AOXaYf7AQuLcGt/T7jkQIxyq3k2VQR1YwfyhiV9PdnysftOH3fSQVXA3LY/pcOYs tFfI5nQahixYmqvF8shgWnV89U5KUXDafOmNCu5ejkvF6OMtCSQkuIIijDHrXFUZgLu7JtWn lFV/l+DKXb1b1g4XZm+hTPG5w/ZgEXxb8orABuVc4cLKRSzmGWoQgSo5sIKzwg3AU2r7lOnO 8y+WH/0ecGlT1cJzeT0 IronPort-HdrOrdr: A9a23:bhfiSas6KOves1Icygs5RCza7skDWNV00zEX/kB9WHVpm62j+P xG+c5x6faaskd3ZJhNo7G90dC7MBbhHP1Oj7X5Q43SODUO41HYT72KhLGKq1eMdxEWkNQts5 uIGJIfNDSfNykAsS/S2njbL/8QhPWB7aC0laP/4h5WPHtXgnhbnn5E49CgYzVLeDU= X-Talos-CUID: =?us-ascii?q?9a23=3AjDuopGlX38Uv+QJOTTRCl9heH5rXOWDQzXXqCEG?= =?us-ascii?q?xNX1CF/6YQ36A3q1Wj8U7zg=3D=3D?= X-Talos-MUID: =?us-ascii?q?9a23=3ACITEng+HKLBi+WbaD3pFT/mQf5hVzYGUNREMqtY?= =?us-ascii?q?bqZi9aDZuHCu3kiviFw=3D=3D?= X-IronPort-AV: E=Sophos;i="6.01,190,1684814400"; d="scan'208";a="120127124" From: Andrew Cooper To: LKML CC: Andrew Cooper , , "Borislav Petkov" , Peter Zijlstra , Josh Poimboeuf , Babu Moger , , Nikolay Borisov , , Thomas Gleixner Subject: [PATCH 0/4] x86/srso: Reduce overhead of the mitigation Date: Mon, 21 Aug 2023 12:27:19 +0100 Message-ID: <20230821112723.3995187-1-andrew.cooper3@citrix.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The main point of this series is patch 4 to remove one taken branch from every function return. Everything else is cleanup. Patch 3 has an issue that sadly may invalidate this as a technique. Patch 4 needs some objtool whispering to fix. Based on x86/urgent but I suspect this may want rebasing around other fixes in flight. Andrew Cooper (4): x86/srso: Rename srso_alias_*() to srso_fam19_*() x86/srso: Rename fam17 SRSO infrastructure to srso_fam17_*() x86/ret-thunk: Support CALL-ing to the ret-thunk x86/srso: Use CALL-based return thunks to reduce overhead arch/x86/include/asm/nospec-branch.h | 9 ++-- arch/x86/kernel/alternative.c | 4 +- arch/x86/kernel/cpu/bugs.c | 9 ++-- arch/x86/kernel/ftrace.c | 8 +-- arch/x86/kernel/static_call.c | 10 ++-- arch/x86/kernel/vmlinux.lds.S | 10 ++-- arch/x86/lib/retpoline.S | 75 ++++++++++++---------------- arch/x86/net/bpf_jit_comp.c | 5 +- 8 files changed, 67 insertions(+), 63 deletions(-) base-commit: 6405b72e8d17bd1875a56ae52d23ec3cd51b9d66 -- 2.30.2