BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3108 The early assembler code performs validation for some of the SEV-related information, specifically the encryption bit position. The new MemEncryptSevGetEncryptionMask() interface provides access to this validated value. To ensure that we always use a validated encryption mask for an SEV-ES guest, update all locations that use CPUID to calculate the encryption mask to use the new interface. Also, clean up some call areas where extra masking was being performed and where a function call was being used instead of the local variable that was just set using the function. Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Ard Biesheuvel <ard.biesheuvel@arm.com> Cc: Rebecca Cran <rebecca@bsdio.com> Cc: Peter Grehan <grehan@freebsd.org> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Anthony Perard <anthony.perard@citrix.com> Cc: Julien Grall <julien@xen.org> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Message-Id: <9de678c0d66443c6cc33e004a4cac0a0223c2ebc.1610045305.git.thomas.lendacky@amd.com>
		
			
				
	
	
		
			57 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			57 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /**@file
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|   Initialize Secure Encrypted Virtualization (SEV) support
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| 
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|   Copyright (c) 2017 - 2020, Advanced Micro Devices. All rights reserved.<BR>
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|   Copyright (c) 2019, Citrix Systems, Inc.
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| 
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|   SPDX-License-Identifier: BSD-2-Clause-Patent
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| 
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| **/
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| //
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| // The package level header files this module uses
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| //
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| #include <Library/DebugLib.h>
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| #include <Library/MemEncryptSevLib.h>
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| #include <Library/PcdLib.h>
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| #include <PiPei.h>
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| 
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| #include "Platform.h"
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| 
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| /**
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| 
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|   Function checks if SEV support is available, if present then it sets
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|   the dynamic PcdPteMemoryEncryptionAddressOrMask with memory encryption mask.
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| 
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|   **/
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| VOID
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| AmdSevInitialize (
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|   VOID
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|   )
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| {
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|   UINT64                            EncryptionMask;
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|   RETURN_STATUS                     PcdStatus;
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| 
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|   //
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|   // Check if SEV is enabled
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|   //
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|   if (!MemEncryptSevIsEnabled ()) {
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|     return;
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|   }
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| 
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|   //
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|   // Set Memory Encryption Mask PCD
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|   //
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|   EncryptionMask = MemEncryptSevGetEncryptionMask ();
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|   PcdStatus = PcdSet64S (PcdPteMemoryEncryptionAddressOrMask, EncryptionMask);
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|   ASSERT_RETURN_ERROR (PcdStatus);
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| 
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|   DEBUG ((DEBUG_INFO, "SEV is enabled (mask 0x%lx)\n", EncryptionMask));
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| 
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|   //
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|   // Set Pcd to Deny the execution of option ROM when security
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|   // violation.
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|   //
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|   PcdStatus = PcdSet32S (PcdOptionRomImageVerificationPolicy, 0x4);
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|   ASSERT_RETURN_ERROR (PcdStatus);
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| }
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