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 1F79BC04E69 for ; Thu, 10 Aug 2023 15:32:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236159AbjHJPcD (ORCPT ); Thu, 10 Aug 2023 11:32:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236178AbjHJPcC (ORCPT ); Thu, 10 Aug 2023 11:32:02 -0400 Received: from smtp-relay-canonical-1.canonical.com (smtp-relay-canonical-1.canonical.com [185.125.188.121]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4815410F3 for ; Thu, 10 Aug 2023 08:31:59 -0700 (PDT) Received: from localhost.localdomain (1.general.cascardo.us.vpn [10.172.70.58]) (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-1.canonical.com (Postfix) with ESMTPSA id CF86C3F16F; Thu, 10 Aug 2023 15:31:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1691681517; bh=gGqfsd30PlPyCv4HGotmPSOPFFtwKjwFLIUg3yKRzZo=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=cNKSKsca9XuUX6in31O28UH4t/ZOXNvJqMQ0aAwOImDAuCVdlq4EmZwCodEqtyWBP eTXWmQuTa63TGbvyeticMLxgrTcVqdCONSVOjiPZYhFnREQRnnpODLfFOk2yacHRYr WbetHjHfRWiDOWOfFw2j4S0C7DPdrMuzZOfQ7ilcvQHNRlcMj8t/dvtbxzEKvPPfUG C9Oi6WcYDo4ndfDj7skOAsavC0NsKTImfyw5N3pBvl7eUIUH3pYWx+CoqAaNY5U/gi HmhtEl5XBVE2Lu0lTQeHciwAvJG6iuV45j9lSr17hylLIhibp0KHfj9reFtqKmJYlc fUQT1kPNJc33Q== From: Thadeu Lima de Souza Cascardo To: stable@vger.kernel.org Cc: RAJESH DASARI , Thomas Gleixner , Borislav Petkov Subject: [PATCH 5.4,5.10] x86/pkeys: Revert a5eff7259790 ("x86/pkeys: Add PKRU value to init_fpstate") Date: Thu, 10 Aug 2023 12:31:06 -0300 Message-Id: <20230810153106.172292-1-cascardo@canonical.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Thomas Gleixner Commit b3607269ff57fd3c9690cb25962c5e4b91a0fd3b upstream. This cannot work and it's unclear how that ever made a difference. init_fpstate.xsave.header.xfeatures is always 0 so get_xsave_addr() will always return a NULL pointer, which will prevent storing the default PKRU value in init_fpstate. Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Reviewed-by: Borislav Petkov Link: https://lkml.kernel.org/r/20210623121451.451391598@linutronix.de Reported-by: RAJESH DASARI Signed-off-by: Thadeu Lima de Souza Cascardo --- This has been reported to cause a WARNing since the backport of b81fac906a8f ("x86/fpu: Move FPU initialization into arch_cpu_finalize_init()"). a5eff7259790 was part of 5.2 and no older LTS kernels carry it, so not necessary on 4.19 or 4.14. --- arch/x86/kernel/cpu/common.c | 5 ----- arch/x86/mm/pkeys.c | 6 ------ 2 files changed, 11 deletions(-) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index fcfe891c1e8e..0c0c2cb038ad 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -450,8 +450,6 @@ static bool pku_disabled; static __always_inline void setup_pku(struct cpuinfo_x86 *c) { - struct pkru_state *pk; - /* check the boot processor, plus compile options for PKU: */ if (!cpu_feature_enabled(X86_FEATURE_PKU)) return; @@ -462,9 +460,6 @@ static __always_inline void setup_pku(struct cpuinfo_x86 *c) return; cr4_set_bits(X86_CR4_PKE); - pk = get_xsave_addr(&init_fpstate.xsave, XFEATURE_PKRU); - if (pk) - pk->pkru = init_pkru_value; /* * Seting X86_CR4_PKE will cause the X86_FEATURE_OSPKE * cpuid bit to be set. We need to ensure that we diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c index c6f84c0b5d7a..ca77af96033b 100644 --- a/arch/x86/mm/pkeys.c +++ b/arch/x86/mm/pkeys.c @@ -10,7 +10,6 @@ #include /* boot_cpu_has, ... */ #include /* vma_pkey() */ -#include /* init_fpstate */ int __execute_only_pkey(struct mm_struct *mm) { @@ -154,7 +153,6 @@ static ssize_t init_pkru_read_file(struct file *file, char __user *user_buf, static ssize_t init_pkru_write_file(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos) { - struct pkru_state *pk; char buf[32]; ssize_t len; u32 new_init_pkru; @@ -177,10 +175,6 @@ static ssize_t init_pkru_write_file(struct file *file, return -EINVAL; WRITE_ONCE(init_pkru_value, new_init_pkru); - pk = get_xsave_addr(&init_fpstate.xsave, XFEATURE_PKRU); - if (!pk) - return -EINVAL; - pk->pkru = new_init_pkru; return count; } -- 2.34.1