From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752789AbeCEQ1K (ORCPT ); Mon, 5 Mar 2018 11:27:10 -0500 Received: from mga07.intel.com ([134.134.136.100]:9033 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752674AbeCEQ0c (ORCPT ); Mon, 5 Mar 2018 11:26:32 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,427,1515484800"; d="scan'208";a="39349304" From: "Kirill A. Shutemov" To: Ingo Molnar , x86@kernel.org, Thomas Gleixner , "H. Peter Anvin" , Tom Lendacky Cc: Dave Hansen , Kai Huang , linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Kirill A. Shutemov" Subject: [RFC, PATCH 19/22] x86/mm: Implement free_encrypt_page() Date: Mon, 5 Mar 2018 19:26:07 +0300 Message-Id: <20180305162610.37510-20-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180305162610.37510-1-kirill.shutemov@linux.intel.com> References: <20180305162610.37510-1-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As on allocation of encrypted page, we need to flush cache before returning page to free pool. Failing to do this may lead to data corruption. Signed-off-by: Kirill A. Shutemov --- arch/x86/mm/mktme.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/x86/mm/mktme.c b/arch/x86/mm/mktme.c index 1129ad25b22a..ef0eb1eb8d6e 100644 --- a/arch/x86/mm/mktme.c +++ b/arch/x86/mm/mktme.c @@ -45,6 +45,19 @@ void prep_encrypt_page(struct page *page, gfp_t gfp, unsigned int order) WARN_ONCE(gfp & __GFP_ZERO, "__GFP_ZERO is useless for encrypted pages"); } +void free_encrypt_page(struct page *page, int keyid, unsigned int order) +{ + int i; + void *v; + + for (i = 0; i < (1 << order); i++) { + v = kmap_atomic_keyid(page, keyid + i); + /* See comment in prep_encrypt_page() */ + clflush_cache_range(v, PAGE_SIZE); + kunmap_atomic(v); + } +} + struct page *__alloc_zeroed_encrypted_user_highpage(gfp_t gfp, struct vm_area_struct *vma, unsigned long vaddr) { -- 2.16.1