From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx4+2QoPFZBzlAItbz1AAjPIKam58lgh4Nma11RKdTujaQVOpwv1xOKlEGVw7c6UE1PieJSJh ARC-Seal: i=1; a=rsa-sha256; t=1523294095; cv=none; d=google.com; s=arc-20160816; b=mgbTEv4tUQIQXkCQexszUdfzm62S5y7bgd1yjVvdRLOjkUR3NYxVhK1CZ9UDSlPog6 RpkR6bF/w49XsH0MhTexcN1n6V3mw2WtLNRxgfEaBHcqHOFin8oFauDFs1tkUPAK+9kq BWhB7x3zJhqXiy8cOvpDqmLiiThSxXW8njNQXrM0/6JEGqOPZYwXmKfY/hqeaEfvLVgF lhI3sQfgU6Sga1izOgEsSQvoXnizf4M/8nSmciTTTPKRHj0gqJTQ1JDA9zn0op421IUP 9wOmafaJrxEbQPDHgNYoCQwKtlTJho7Siu05rGDAjzi9BAwAHr06zhvWRgZUHziRaKOT Pz9A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=precedence:content-disposition:content-transfer-encoding :mime-version:robot-unsubscribe:robot-id:git-commit-id:subject:to :references:in-reply-to:reply-to:cc:message-id:from:sender:date :arc-authentication-results; bh=79OdL8ByQVnc8Vqglpd73cx2itHLr9x0E3tQXBZXogI=; b=vDzIfTrgnHOL6ssXQQwxu8nT6/aiX+94Dv8m4sQ30fwURV2cZsgJGL8R5U5sBaQ+YN FeBrZwaT98q5OsKygWBk1J4Tr87FFgbvJDMUDxifQRKSoxIUj0UaPMpIkwFKuN03953P 1sre39/QMx2KApwxDxQtz3838d71ZQgVgngk+PQEJbC2azRdgpbbqWSnqEZxiYOSUjcy r8cP7wvCbd1CTtP9uNziqpxIodcvs+6pXEU9OaB2ns+a+0JFhYf8v0mbpEiBFUsU1ZRz F22wI/mhBxnwLV8kJ0D0XhTu1fj+KiObsBPSc2PMfAqD2mYIe0j30KnJ145NOh+F8QTD VUqA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of tipbot@zytor.com designates 198.137.202.136 as permitted sender) smtp.mailfrom=tipbot@zytor.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of tipbot@zytor.com designates 198.137.202.136 as permitted sender) smtp.mailfrom=tipbot@zytor.com Date: Mon, 9 Apr 2018 10:14:13 -0700 Sender: tip tree robot From: tip-bot for Dave Hansen Message-ID: Cc: torvalds@linux-foundation.org, mingo@kernel.org, keescook@google.com, dave.hansen@linux.intel.com, dan.j.williams@intel.com, tglx@linutronix.de, bp@alien8.de, peterz@infradead.org, dwmw2@infradead.org, aarcange@redhat.com, namit@vmware.com, luto@kernel.org, jgross@suse.com, hughd@google.com, hpa@zytor.com, arjan@linux.intel.com, jpoimboe@redhat.com, linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org Reply-To: jgross@suse.com, aarcange@redhat.com, namit@vmware.com, luto@kernel.org, jpoimboe@redhat.com, linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, hughd@google.com, hpa@zytor.com, arjan@linux.intel.com, dave.hansen@linux.intel.com, torvalds@linux-foundation.org, mingo@kernel.org, keescook@google.com, peterz@infradead.org, dwmw2@infradead.org, dan.j.williams@intel.com, tglx@linutronix.de, bp@alien8.de In-Reply-To: <20180406205511.BC072352@viggo.jf.intel.com> References: <20180406205511.BC072352@viggo.jf.intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/pti] x86/mm: Remove extra filtering in pageattr code Git-Commit-ID: e71e836f463dd2cfb319ce88ae4a6e4f83904e6c X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1597289629374494511?= X-GMAIL-MSGID: =?utf-8?q?1597289629374494511?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Commit-ID: e71e836f463dd2cfb319ce88ae4a6e4f83904e6c Gitweb: https://git.kernel.org/tip/e71e836f463dd2cfb319ce88ae4a6e4f83904e6c Author: Dave Hansen AuthorDate: Fri, 6 Apr 2018 13:55:11 -0700 Committer: Ingo Molnar CommitDate: Mon, 9 Apr 2018 18:27:33 +0200 x86/mm: Remove extra filtering in pageattr code The pageattr code has a mode where it can set or clear PTE bits in existing PTEs, so the page protections of the *new* PTEs come from one of two places: 1. The set/clear masks: cpa->mask_clr / cpa->mask_set 2. The existing PTE We filter ->mask_set/clr for supported PTE bits at entry to __change_page_attr() so we never need to filter them again. The only other place permissions can come from is an existing PTE and those already presumably have good bits. We do not need to filter them again. Signed-off-by: Dave Hansen Cc: Andrea Arcangeli Cc: Andy Lutomirski Cc: Arjan van de Ven Cc: Borislav Petkov Cc: Dan Williams Cc: David Woodhouse Cc: Greg Kroah-Hartman Cc: Hugh Dickins Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Kees Cook Cc: Linus Torvalds Cc: Nadav Amit Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20180406205511.BC072352@viggo.jf.intel.com Signed-off-by: Ingo Molnar --- arch/x86/mm/pageattr.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index d3442dfdfced..968f51a2e39b 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -598,7 +598,6 @@ try_preserve_large_page(pte_t *kpte, unsigned long address, req_prot = pgprot_clear_protnone_bits(req_prot); if (pgprot_val(req_prot) & _PAGE_PRESENT) pgprot_val(req_prot) |= _PAGE_PSE; - req_prot = canon_pgprot(req_prot); /* * old_pfn points to the large page base pfn. So we need @@ -718,7 +717,7 @@ __split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address, */ pfn = ref_pfn; for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc) - set_pte(&pbase[i], pfn_pte(pfn, canon_pgprot(ref_prot))); + set_pte(&pbase[i], pfn_pte(pfn, ref_prot)); if (virt_addr_valid(address)) { unsigned long pfn = PFN_DOWN(__pa(address)); @@ -935,7 +934,6 @@ static void populate_pte(struct cpa_data *cpa, pte = pte_offset_kernel(pmd, start); pgprot = pgprot_clear_protnone_bits(pgprot); - pgprot = canon_pgprot(pgprot); while (num_pages-- && start < end) { set_pte(pte, pfn_pte(cpa->pfn, pgprot)); @@ -1234,7 +1232,7 @@ repeat: * after all we're only going to change it's attributes * not the memory it points to */ - new_pte = pfn_pte(pfn, canon_pgprot(new_prot)); + new_pte = pfn_pte(pfn, new_prot); cpa->pfn = pfn; /* * Do we really change anything ?