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[2001:1868:205::9]) by mx.google.com with ESMTPS id ly8si5825487pab.89.2016.02.24.08.24.57 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 24 Feb 2016 08:24:57 -0800 (PST) Received-SPF: pass (google.com: best guess record for 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: best guess record for 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; dkim=neutral (body hash did not verify) header.i=@linaro.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 1aYcDl-0006j4-TU; Wed, 24 Feb 2016 16:23:25 +0000 Received: from mail-wm0-x236.google.com ([2a00:1450:400c:c09::236]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aYcCX-0005Uk-KK for linux-arm-kernel@lists.infradead.org; Wed, 24 Feb 2016 16:22:15 +0000 Received: by mail-wm0-x236.google.com with SMTP id a4so37335553wme.1 for ; Wed, 24 Feb 2016 08:21:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=ATNV4BSKoYfG3frEGC97i5Q3RtCX+jdylMGKhLJpnW8=; b=Z2hKjngxrA2GfxavqiWjSr7ddRq8PQH+09Ae9DRrpxfzb5gqSYt0D09rqjl/7CcfsF k1235mfcafO24B5PgSJUmwFGO7wrXFMn351ccM4VrY/0bEFO6gCGn7kHiUhfhPVqySO+ AkvA61EC1m7CJJRcFsMugGHJEV/ZCqpOWGE8M= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=ATNV4BSKoYfG3frEGC97i5Q3RtCX+jdylMGKhLJpnW8=; b=RgPyRZ4gKsPyv9C55tbHOUoz+UBVHAaGzS1GyDWMrc9T+dSMalYB+Xbwx5XUavTqtI IenEWEMSTzui8s6JTjgtYUc4cbOZ8chFlgADuVlpp5XhSWWzvZVztzKGu2BYWPA92IjX 3umIDipt+34FCZciw3IWurm2A37MPU0J+oUEhvf38JhzWcni2dLEmtF+U/kkA6fnW5ps TMDuiQ7GtqsHRiZcQQTETmUYXtPB1wV8HXVjSsoJ/FcGILZQiA1tviUbKijGIXJWOuTN jmRvir8JqUvdTphPhmCRdL7G5McBisjYReM2YpEWisOtLNnWOT3WrDJGzwqb4xD+aKyL VpIQ== X-Gm-Message-State: AG10YORyFCkRP4NdPagn9DGK1Rkg9pUMDG4HhSBOQeSlRSioq0knkLl4uMo52KoznBO8HbIH X-Received: by 10.28.33.84 with SMTP id h81mr26282670wmh.36.1456330907797; Wed, 24 Feb 2016 08:21:47 -0800 (PST) Received: from localhost.localdomain ([195.55.142.58]) by smtp.gmail.com with ESMTPSA id gb9sm3730412wjb.26.2016.02.24.08.21.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 24 Feb 2016 08:21:47 -0800 (PST) From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, will.deacon@arm.com Subject: [RFC PATCH 4/6] arm64: mm: avoid virt_to_page() translation for the zero page Date: Wed, 24 Feb 2016 17:21:31 +0100 Message-Id: <1456330893-19228-5-git-send-email-ard.biesheuvel@linaro.org> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1456330893-19228-1-git-send-email-ard.biesheuvel@linaro.org> References: <1456330893-19228-1-git-send-email-ard.biesheuvel@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160224_082210_061308_BFF8A235 X-CRM114-Status: GOOD ( 10.34 ) X-Spam-Score: -2.7 (--) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-2.7 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [2a00:1450:400c:c09:0:0:0:236 listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 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@arm.com, Ard Biesheuvel MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org The zero page is statically allocated, so grab its struct page pointer without using virt_to_page(), which will be restricted to the linear mapping later. Signed-off-by: Ard Biesheuvel --- arch/arm64/include/asm/pgtable.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.5.0 _______________________________________________ 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/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 8e6baea0ff61..ab84cafde3c9 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -118,7 +118,7 @@ extern void __pgd_error(const char *file, int line, unsigned long val); * for zero-mapped memory areas etc.. */ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]; -#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page) +#define ZERO_PAGE(vaddr) pfn_to_page(__pa(empty_zero_page) >> PAGE_SHIFT) #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte_val(pte))