Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753190AbbHNWib (ORCPT ); Fri, 14 Aug 2015 18:38:31 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:35180 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753000AbbHNWi3 (ORCPT ); Fri, 14 Aug 2015 18:38:29 -0400 From: "Jonathan (Zhixiong) Zhang" To: Will Deacon , Ingo Molnar , Thomas Gleixner , "H . Peter Anvin" , "linux-kernel @ vger . kernel . org" , "linux-efi @ vger . kernel . org" , Matt Fleming , Borislav Petkov , Ard Biesheuvel , Catalin Marinas , Matt Fleming Cc: "Jonathan (Zhixiong) Zhang" Subject: [PATCH 2/2] acpi, apei: use appropriate pgprot_t to map GHES memory Date: Fri, 14 Aug 2015 15:37:30 -0700 Message-Id: <1439591850-29002-2-git-send-email-zjzhang@codeaurora.org> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1439591850-29002-1-git-send-email-zjzhang@codeaurora.org> References: <1439591850-29002-1-git-send-email-zjzhang@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1848 Lines: 47 From: "Jonathan (Zhixiong) Zhang" With ACPI APEI firmware first handling, generic hardware error record is updated by firmware in GHES memory region. On an arm64 platform, firmware updates GHES memory region with uncached access attribute, and then Linux reads stale data from cache. With current code, GHES memory region is mapped with PAGE_KERNEL based on the assumption that cache coherency of GHES memory region is maintained by firmware on all platforms. This assumption is not true for above mentioned arm64 platform. Instead GHES memory region should be mapped with page protection type according to what is returned from arch_apei_get_mem_attribute(). Acked-by: Borislav Petkov Signed-off-by: Jonathan (Zhixiong) Zhang --- drivers/acpi/apei/ghes.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 23981ac1c6c2..f742335bd8bb 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -160,8 +160,10 @@ static void __iomem *ghes_ioremap_pfn_irq(u64 pfn) unsigned long vaddr; vaddr = (unsigned long)GHES_IOREMAP_IRQ_PAGE(ghes_ioremap_area->addr); - ioremap_page_range(vaddr, vaddr + PAGE_SIZE, - pfn << PAGE_SHIFT, PAGE_KERNEL); + ioremap_page_range(vaddr, + vaddr + PAGE_SIZE, + pfn << PAGE_SHIFT, + arch_apei_get_mem_attribute(pfn << PAGE_SHIFT)); return (void __iomem *)vaddr; } -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- 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/