From: Tom Lendacky <thomas.lendacky@amd.com>
Subject: [RFC PATCH v1 12/18] x86: Access device tree in the clear
To: <linux-arch@vger.kernel.org>, <linux-efi@vger.kernel.org>,
        <kvm@vger.kernel.org>, <linux-doc@vger.kernel.org>, <x86@kernel.org>,
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CC: Radim =?utf-8?b?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>, Jonathan Corbet <corbet@lwn.net>,
        Matt Fleming <matt@codeblueprint.co.uk>,
        Joerg Roedel <joro@8bytes.org>,
        "Konrad Rzeszutek Wilk" <konrad.wilk@oracle.com>,
        Paolo Bonzini <pbonzini@redhat.com>, "Ingo Molnar" <mingo@redhat.com>,
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Date: Tue, 26 Apr 2016 17:58:00 -0500
Message-ID: <20160426225800.13567.99120.stgit@tlendack-t1.amdoffice.net>
In-Reply-To: <20160426225553.13567.19459.stgit@tlendack-t1.amdoffice.net>
References: <20160426225553.13567.19459.stgit@tlendack-t1.amdoffice.net>
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The device tree is not encrypted and needs to be accessed as such. Be sure
to memmap it without the encryption mask set.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/kernel/devicetree.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
index 3fe45f8..ff11f7a 100644
--- a/arch/x86/kernel/devicetree.c
+++ b/arch/x86/kernel/devicetree.c
@@ -22,6 +22,7 @@
 #include <asm/pci_x86.h>
 #include <asm/setup.h>
 #include <asm/i8259.h>
+#include <asm/mem_encrypt.h>
 
 __initdata u64 initial_dtb;
 char __initdata cmd_line[COMMAND_LINE_SIZE];
@@ -276,11 +277,12 @@ static void __init x86_flattree_get_config(void)
 
 	map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
 
-	initial_boot_params = dt = early_memremap(initial_dtb, map_len);
+	initial_boot_params = dt = sme_early_memremap(initial_dtb, map_len);
 	size = of_get_flat_dt_size();
 	if (map_len < size) {
 		early_memunmap(dt, map_len);
-		initial_boot_params = dt = early_memremap(initial_dtb, size);
+		initial_boot_params = dt = sme_early_memremap(initial_dtb,
+							      size);
 		map_len = size;
 	}