From patchwork Mon Apr 4 20:16:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thadeu Lima de Souza Cascardo X-Patchwork-Id: 1613165 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=canonical.com header.i=@canonical.com header.a=rsa-sha256 header.s=20210705 header.b=Nt4BNG3x; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4KXMWc2Mq1z9sCD for ; Tue, 5 Apr 2022 06:17:15 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1nbT8K-0001yi-Tz; Mon, 04 Apr 2022 20:17:04 +0000 Received: from smtp-relay-canonical-0.internal ([10.131.114.83] helo=smtp-relay-canonical-0.canonical.com) by huckleberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1nbT8I-0001w5-Qw for kernel-team@lists.ubuntu.com; Mon, 04 Apr 2022 20:17:02 +0000 Received: from quatroqueijos.. (unknown [179.93.182.122]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-0.canonical.com (Postfix) with ESMTPSA id 788A33F1B8 for ; Mon, 4 Apr 2022 20:17:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1649103422; bh=Zfu7zKCVUnGXEYz6bXLSPCC5SGJ8mKflcQ737aTMooI=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=Nt4BNG3xM/9pJY9eD3Jc5ujz+zMId4uaudlASzq7mW1ItRUzle1qJHtW8HRLt1pJs ThQuazHj2sWx5toLOU29fyTihwgXRSARKLViPPLf7b1xXrdl2n4P5H3AJJASwa7GfQ EdqkKhzOClQlNZsTqVhP/kZZ7LpEWkyGiHzuT3YUqI9ICFpIM0CQATg0QKS8MhzxnQ rKy2wfsixnKtNvehE9hrrD9OrCjqOksUhlv39gpZmm8YsuuNAUrUKf2gE7SajZYSQf UvlptZIO2rDZhjK0aA6NzaGr1ABic2OFiyLlLOORlNnjqQZcT9wmM3C2IOTCpHPwF2 qmbxHNZxjgpSQ== From: Thadeu Lima de Souza Cascardo To: kernel-team@lists.ubuntu.com Subject: [SRU Bionic/Focal/Impish 0/5] Spectre-BHB followups Date: Mon, 4 Apr 2022 17:16:28 -0300 Message-Id: <20220404201643.87121-1-cascardo@canonical.com> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" [Impact] The LFENCE mitigation was found out not to be sufficient on AMD systems. And unprivileged eBPF was considered in the mitigation status for Spectre v2. [Fixes] "x86/speculation: Include unprivileged eBPF status in Spectre v2 mitigation reporting" need to be backported from close upstream stable branches. [Potential regression] Mitigations may not be applied correctly and changing unprivileged eBPF setting may cause surprising effects. Mitigations may be reported incorrectly or incompletely. Josh Poimboeuf (3): x86/speculation: Include unprivileged eBPF status in Spectre v2 mitigation reporting x86/speculation: Warn about Spectre v2 LFENCE mitigation x86/speculation: Warn about eIBRS + LFENCE + Unprivileged eBPF + SMT Kim Phillips (2): x86/speculation: Use generic retpoline by default on AMD x86/speculation: Update link to AMD speculation whitepaper Documentation/admin-guide/hw-vuln/spectre.rst | 6 +- arch/x86/kernel/cpu/bugs.c | 71 +++++++++++++++---- include/linux/bpf.h | 11 +++ kernel/sysctl.c | 8 +++ 4 files changed, 79 insertions(+), 17 deletions(-) Acked-by: Stefan Bader Acked-by: Tim Gardner