Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756515AbbHYV7X (ORCPT ); Tue, 25 Aug 2015 17:59:23 -0400 Received: from g2t2352.austin.hp.com ([15.217.128.51]:42083 "EHLO g2t2352.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751739AbbHYV50 (ORCPT ); Tue, 25 Aug 2015 17:57:26 -0400 From: Toshi Kani To: hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com Cc: akpm@linux-foundation.org, bp@alien8.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org, x86@kernel.org, jgross@suse.com, konrad.wilk@oracle.com, elliott@hp.com, Toshi Kani Subject: [PATCH v4 7/11] x86/mm: Fix slow_virt_to_phys() to handle large PAT bit Date: Tue, 25 Aug 2015 15:55:07 -0600 Message-Id: <1440539711-2985-8-git-send-email-toshi.kani@hp.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1440539711-2985-1-git-send-email-toshi.kani@hp.com> References: <1440539711-2985-1-git-send-email-toshi.kani@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2148 Lines: 65 slow_virt_to_phys() calls lookup_address() to obtain *pte and its level. It then calls pte_pfn() to obtain a physical address for any level. However, this physical address is not correct when the large PAT bit is set because pte_pfn() does not mask the large PAT bit properly for PUD/PMD. Fix slow_virt_to_phys() to use pud_pfn() and pmd_pfn() for 1GB and 2MB mapping levels. Signed-off-by: Toshi Kani Cc: Juergen Gross Cc: Thomas Gleixner Cc: H. Peter Anvin Cc: Ingo Molnar Cc: Borislav Petkov Cc: Andrew Morton --- arch/x86/mm/pageattr.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index b6c2659..023b639 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -415,18 +415,28 @@ pmd_t *lookup_pmd_address(unsigned long address) phys_addr_t slow_virt_to_phys(void *__virt_addr) { unsigned long virt_addr = (unsigned long)__virt_addr; - phys_addr_t phys_addr; - unsigned long offset; + unsigned long phys_addr, offset; enum pg_level level; - unsigned long pmask; pte_t *pte; pte = lookup_address(virt_addr, &level); BUG_ON(!pte); - pmask = page_level_mask(level); - offset = virt_addr & ~pmask; - phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT; - return (phys_addr | offset); + + switch (level) { + case PG_LEVEL_1G: + phys_addr = pud_pfn(*(pud_t *)pte) << PAGE_SHIFT; + offset = virt_addr & ~PUD_PAGE_MASK; + break; + case PG_LEVEL_2M: + phys_addr = pmd_pfn(*(pmd_t *)pte) << PAGE_SHIFT; + offset = virt_addr & ~PMD_PAGE_MASK; + break; + default: + phys_addr = pte_pfn(*pte) << PAGE_SHIFT; + offset = virt_addr & ~PAGE_MASK; + } + + return (phys_addr_t)(phys_addr | offset); } EXPORT_SYMBOL_GPL(slow_virt_to_phys); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/