mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
synced 2025-01-06 05:02:31 +00:00
8260b9820f
INS/OUTS are not supported in TDX guests and cause #UD. Kernel has to avoid them when running in TDX guest. To support existing usage, string I/O operations are unrolled using IN/OUT instructions. AMD SEV platform implements this support by adding unroll logic in ins#bwl()/outs#bwl() macros with SEV-specific checks. Since TDX VM guests will also need similar support, use CC_ATTR_GUEST_UNROLL_STRING_IO and generic cc_platform_has() API to implement it. String I/O helpers were the last users of sev_key_active() interface and sev_enable_key static key. Remove them. [ bp: Move comment too and do not delete it. ] Suggested-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20211206135505.75045-2-kirill.shutemov@linux.intel.com
100 lines
2.6 KiB
C
100 lines
2.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Confidential Computing Platform Capability checks
|
|
*
|
|
* Copyright (C) 2021 Advanced Micro Devices, Inc.
|
|
*
|
|
* Author: Tom Lendacky <thomas.lendacky@amd.com>
|
|
*/
|
|
|
|
#ifndef _LINUX_CC_PLATFORM_H
|
|
#define _LINUX_CC_PLATFORM_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/stddef.h>
|
|
|
|
/**
|
|
* enum cc_attr - Confidential computing attributes
|
|
*
|
|
* These attributes represent confidential computing features that are
|
|
* currently active.
|
|
*/
|
|
enum cc_attr {
|
|
/**
|
|
* @CC_ATTR_MEM_ENCRYPT: Memory encryption is active
|
|
*
|
|
* The platform/OS is running with active memory encryption. This
|
|
* includes running either as a bare-metal system or a hypervisor
|
|
* and actively using memory encryption or as a guest/virtual machine
|
|
* and actively using memory encryption.
|
|
*
|
|
* Examples include SME, SEV and SEV-ES.
|
|
*/
|
|
CC_ATTR_MEM_ENCRYPT,
|
|
|
|
/**
|
|
* @CC_ATTR_HOST_MEM_ENCRYPT: Host memory encryption is active
|
|
*
|
|
* The platform/OS is running as a bare-metal system or a hypervisor
|
|
* and actively using memory encryption.
|
|
*
|
|
* Examples include SME.
|
|
*/
|
|
CC_ATTR_HOST_MEM_ENCRYPT,
|
|
|
|
/**
|
|
* @CC_ATTR_GUEST_MEM_ENCRYPT: Guest memory encryption is active
|
|
*
|
|
* The platform/OS is running as a guest/virtual machine and actively
|
|
* using memory encryption.
|
|
*
|
|
* Examples include SEV and SEV-ES.
|
|
*/
|
|
CC_ATTR_GUEST_MEM_ENCRYPT,
|
|
|
|
/**
|
|
* @CC_ATTR_GUEST_STATE_ENCRYPT: Guest state encryption is active
|
|
*
|
|
* The platform/OS is running as a guest/virtual machine and actively
|
|
* using memory encryption and register state encryption.
|
|
*
|
|
* Examples include SEV-ES.
|
|
*/
|
|
CC_ATTR_GUEST_STATE_ENCRYPT,
|
|
|
|
/**
|
|
* @CC_ATTR_GUEST_UNROLL_STRING_IO: String I/O is implemented with
|
|
* IN/OUT instructions
|
|
*
|
|
* The platform/OS is running as a guest/virtual machine and uses
|
|
* IN/OUT instructions in place of string I/O.
|
|
*
|
|
* Examples include TDX guest & SEV.
|
|
*/
|
|
CC_ATTR_GUEST_UNROLL_STRING_IO,
|
|
};
|
|
|
|
#ifdef CONFIG_ARCH_HAS_CC_PLATFORM
|
|
|
|
/**
|
|
* cc_platform_has() - Checks if the specified cc_attr attribute is active
|
|
* @attr: Confidential computing attribute to check
|
|
*
|
|
* The cc_platform_has() function will return an indicator as to whether the
|
|
* specified Confidential Computing attribute is currently active.
|
|
*
|
|
* Context: Any context
|
|
* Return:
|
|
* * TRUE - Specified Confidential Computing attribute is active
|
|
* * FALSE - Specified Confidential Computing attribute is not active
|
|
*/
|
|
bool cc_platform_has(enum cc_attr attr);
|
|
|
|
#else /* !CONFIG_ARCH_HAS_CC_PLATFORM */
|
|
|
|
static inline bool cc_platform_has(enum cc_attr attr) { return false; }
|
|
|
|
#endif /* CONFIG_ARCH_HAS_CC_PLATFORM */
|
|
|
|
#endif /* _LINUX_CC_PLATFORM_H */
|