From mboxrd@z Thu Jan 1 00:00:00 1970 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 9F8B79446 for ; Sun, 13 Aug 2023 21:40:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DBA70C433C7; Sun, 13 Aug 2023 21:40:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1691962813; bh=XonbXjtX4fr/jxXaqWPO3He07W4rCIOAc80OoMl3DLo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=v0iOw8LM3lvA4cXvq0ctHFsX/Kit4FddIYyXyP345UM/Hg622J+nd0Peyl1xvjjES /AG137cnCoUwszbDsR3jIjZwEBfC+dJu+QhTKec42mDvRkrGlz5bCfZSf6r08UOSwR tjylkCXstDLjdKL9xOnqQP9+SkgLd4uhGDeZjqwc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Thomas Gleixner , Borislav Petkov , Thadeu Lima de Souza Cascardo Subject: [PATCH 5.10 17/68] x86/pkeys: Revert a5eff7259790 ("x86/pkeys: Add PKRU value to init_fpstate") Date: Sun, 13 Aug 2023 23:19:18 +0200 Message-ID: <20230813211708.678961745@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230813211708.149630011@linuxfoundation.org> References: <20230813211708.149630011@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/common.c | 5 ----- arch/x86/mm/pkeys.c | 6 ------ 2 files changed, 11 deletions(-) --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -472,8 +472,6 @@ 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; @@ -484,9 +482,6 @@ static __always_inline void setup_pku(st 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 --- 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(struc 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(stru 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; }