From patchwork Tue Apr 8 21:47:29 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josh Poimboeuf X-Patchwork-Id: 14043728 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0E07824A075; Tue, 8 Apr 2025 21:48:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744148882; cv=none; b=Z+bG03W7xwyEVQf1e4KH1/+yjNVCLXGYwAYkNJrfmtnlnnR/p/hTJUaWu3IxqwMxMGgvLa6JwVK0yJzxxDjRsuwueiNdjIqeNYPxCiO0VYoittMMK3dYX60HK6XMYzVBHO4OeVH4AYzH4yqP/dRf9WtVb2x2Z3kzX8JqiOhRLUo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744148882; c=relaxed/simple; bh=6COeFnaQgN3qls/u+Yq5ZtwKJF9Vw4Z42v5LKtiDZzk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=PwUUhya6HAcjaZATDMPOUB1H23hzirG3g4UQFOnJqKKj7WZE9wnSpiAXoumYZaM7xumxPwWtq7ya1OnOxHy3DOs0lkj0en8EOSEJSm+SEWeuuLfOTmlTucVWrHgOcmbIcRSu6eg/RGUA4pmQPH5UycoQMPqlkJSgd0WH3aIpKTA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tJJWuO/y; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tJJWuO/y" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A91CEC4CEE5; Tue, 8 Apr 2025 21:48:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1744148881; bh=6COeFnaQgN3qls/u+Yq5ZtwKJF9Vw4Z42v5LKtiDZzk=; h=From:To:Cc:Subject:Date:From; b=tJJWuO/yEomXExrdB/E8GR2veu7Li5zKPfZ561v3TzNYrIrXjkBDgHGBONCoCCIXh tKkqxCuMgSyWsUWItNFLbhffFGpdwNOSiyKSPiK3rmuAse3fE/uTaAtpyZ40a5wdkG ILvoOT9SSoWc4pdCu2ZBDfKB38X/27ISo7lJY7N1sXRvJos3yTVlnT7h2ILv8Q1/Yw YovlEJMFAuyjNrYRVYCK4X6HvFR7HyAxqHiCX3zBCPIQh6DFVIfv+Sy23ZN/DY41iQ bVvZr5T73h2oCTHTxJAvKsd8rzD3W7+YpEaNpZku69VJD57LcHtDdv3a9T1U9FNk5y mZ4VyqhuiBEew== From: Josh Poimboeuf To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, amit@kernel.org, kvm@vger.kernel.org, amit.shah@amd.com, thomas.lendacky@amd.com, bp@alien8.de, tglx@linutronix.de, peterz@infradead.org, pawan.kumar.gupta@linux.intel.com, corbet@lwn.net, mingo@redhat.com, dave.hansen@linux.intel.com, hpa@zytor.com, seanjc@google.com, pbonzini@redhat.com, daniel.sneddon@linux.intel.com, kai.huang@intel.com, sandipan.das@amd.com, boris.ostrovsky@oracle.com, Babu.Moger@amd.com, david.kaplan@amd.com, dwmw@amazon.co.uk, andrew.cooper3@citrix.comm, nik.borisov@suse.com Subject: [PATCH v4 0/6] x86/bugs: RSB mitigation fixes and documentation Date: Tue, 8 Apr 2025 14:47:29 -0700 Message-ID: X-Mailer: git-send-email 2.49.0 Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 v4: - improve document - remove C++ comment - "__write_ibpb" -> "write-ibpb" - improve commit logs v3: https://lore.kernel.org/cover.1743617897.git.jpoimboe@kernel.org Josh Poimboeuf (6): x86/bugs: Rename entry_ibpb() to write_ibpb() x86/bugs: Use SBPB in write_ibpb() if applicable x86/bugs: Fix RSB clearing in indirect_branch_prediction_barrier() x86/bugs: Don't fill RSB on VMEXIT with eIBRS+retpoline x86/bugs: Don't fill RSB on context switch with eIBRS x86/bugs: Add RSB mitigation document Documentation/admin-guide/hw-vuln/index.rst | 1 + Documentation/admin-guide/hw-vuln/rsb.rst | 268 ++++++++++++++++++++ arch/x86/entry/entry.S | 9 +- arch/x86/include/asm/nospec-branch.h | 12 +- arch/x86/kernel/cpu/bugs.c | 107 +++----- arch/x86/mm/tlb.c | 6 +- 6 files changed, 317 insertions(+), 86 deletions(-) create mode 100644 Documentation/admin-guide/hw-vuln/rsb.rst