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[2001:1868:205::9]) by mx.google.com with ESMTPS id ua7si18608595pac.65.2015.11.23.03.11.49 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 23 Nov 2015 03:11:49 -0800 (PST) Received-SPF: pass (google.com: domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) client-ip=2001:1868:205::9; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) smtp.mailfrom=linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1a0p0J-0000rH-5W; Mon, 23 Nov 2015 11:09:51 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1a0p0F-0000ol-TM for linux-arm-kernel@lists.infradead.org; Mon, 23 Nov 2015 11:09:48 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4A53649; Mon, 23 Nov 2015 03:09:08 -0800 (PST) Received: from leverpostej.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 180673F21A; Mon, 23 Nov 2015 03:09:23 -0800 (PST) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Subject: [PATCHv3] arm64: efi: correctly map runtime regions Date: Mon, 23 Nov 2015 11:09:11 +0000 Message-Id: <1448276951-13335-1-git-send-email-mark.rutland@arm.com> X-Mailer: git-send-email 1.9.1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151123_030947_969106_95761C05 X-CRM114-Status: GOOD ( 10.98 ) X-Spam-Score: -7.5 (-------) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-7.5 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [217.140.101.70 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.6 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Catalin Marinas , Will Deacon , Leif Lindholm , ard.biesheuvel@linaro.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org The kernel may use a page granularity of 4K, 16K, or 64K depending on configuration. When mapping EFI runtime regions, we use memrange_efi_to_native to round the physical base address of a region down to a kernel page boundary, and round the size up to a kernel page boundary, adding the residue left over from rounding down the physical base address. We do not round down the virtual base address. In __create_mapping we account for the offset of the virtual base from a granule boundary, adding the residue to the size before rounding the base down to said granule boundary. Thus we account for the residue twice, and when the residue is non-zero will cause __create_mapping to map an additional page at the end of the region. Depending on the memory map, this page may be in a region we are not intended/permitted to map, or may clash with a different region that we wish to map. In typical cases, mapping the next item in the memory map will overwrite the erroneously created entry, as we sort the memory map in the stub. As __create_mapping can cope with base addresses which are not page aligned, we can instead rely on it to map the region appropriately, and simplify efi_virtmap_init by removing the unnecessary code. Signed-off-by: Mark Rutland Reviewed-by: Ard Biesheuvel Cc: Catalin Marinas Cc: Leif Lindholm Cc: Will Deacon --- arch/arm64/kernel/efi.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) Since v1 [1]: * Rely on create_pgd_mapping to handle alignment. Since v2 [2]: * Describe why this case is unlikely in practice. * Calculate size in create_pgd_mapping_call. * Rebase to v4.4-rc2, avoiding clash with [3]. Mark. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-November/386536.html [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-November/386908.html [3] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-November/385524.html -- 1.9.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index fc5508e..fe7cd1a 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -227,7 +227,6 @@ static bool __init efi_virtmap_init(void) init_new_context(NULL, &efi_mm); for_each_efi_memory_desc(&memmap, md) { - u64 paddr, npages, size; pgprot_t prot; if (!(md->attribute & EFI_MEMORY_RUNTIME)) @@ -235,11 +234,6 @@ static bool __init efi_virtmap_init(void) if (md->virt_addr == 0) return false; - paddr = md->phys_addr; - npages = md->num_pages; - memrange_efi_to_native(&paddr, &npages); - size = npages << PAGE_SHIFT; - pr_info(" EFI remap 0x%016llx => %p\n", md->phys_addr, (void *)md->virt_addr); @@ -256,7 +250,8 @@ static bool __init efi_virtmap_init(void) else prot = PAGE_KERNEL; - create_pgd_mapping(&efi_mm, paddr, md->virt_addr, size, + create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr, + md->num_pages << EFI_PAGE_SHIFT, __pgprot(pgprot_val(prot) | PTE_NG)); } return true;