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![Borislav Petkov](/assets/img/avatar_default.png)
The SME encryption mask is for masking 64-bit pagetable entries. It
being an unsigned long works fine on X86_64 but on 32-bit builds in
truncates bits leading to Xen guests crashing very early.
And regardless, the whole SME mask handling shouldnt've leaked into
32-bit because SME is X86_64-only feature. So, first make the mask u64.
And then, add trivial 32-bit versions of the __sme_* macros so that
nothing happens there.
Reported-and-tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tom Lendacky <Thomas.Lendacky@amd.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas <Thomas.Lendacky@amd.com>
Fixes: 21729f81ce
("x86/mm: Provide general kernel support for memory encryption")
Link: http://lkml.kernel.org/r/20170907093837.76zojtkgebwtqc74@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
53 lines
1.1 KiB
C
53 lines
1.1 KiB
C
/*
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* AMD Memory Encryption Support
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*
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* Copyright (C) 2016 Advanced Micro Devices, Inc.
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*
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* Author: Tom Lendacky <thomas.lendacky@amd.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#ifndef __MEM_ENCRYPT_H__
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#define __MEM_ENCRYPT_H__
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#ifndef __ASSEMBLY__
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#ifdef CONFIG_ARCH_HAS_MEM_ENCRYPT
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#include <asm/mem_encrypt.h>
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#else /* !CONFIG_ARCH_HAS_MEM_ENCRYPT */
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#define sme_me_mask 0ULL
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#endif /* CONFIG_ARCH_HAS_MEM_ENCRYPT */
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static inline bool sme_active(void)
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{
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return !!sme_me_mask;
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}
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static inline u64 sme_get_me_mask(void)
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{
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return sme_me_mask;
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}
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#ifdef CONFIG_AMD_MEM_ENCRYPT
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/*
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* The __sme_set() and __sme_clr() macros are useful for adding or removing
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* the encryption mask from a value (e.g. when dealing with pagetable
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* entries).
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*/
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#define __sme_set(x) ((x) | sme_me_mask)
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#define __sme_clr(x) ((x) & ~sme_me_mask)
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#else
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#define __sme_set(x) (x)
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#define __sme_clr(x) (x)
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#endif
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#endif /* __ASSEMBLY__ */
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#endif /* __MEM_ENCRYPT_H__ */
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