linux/arch/x86/kernel/cc_platform.c
Linus Torvalds cb3f09f9af hyperv-next for 5.17
-----BEGIN PGP SIGNATURE-----
 
 iQFHBAABCAAxFiEEIbPD0id6easf0xsudhRwX5BBoF4FAmHhw7oTHHdlaS5saXVA
 a2VybmVsLm9yZwAKCRB2FHBfkEGgXrjSB/979LV4Dn1PMcFYsSdlFEMeHcjzJdw/
 kFnLPXMaPJyfg6QPuf83jxzw9uxw8fcePMdVq/FFBtmVV9fJMAv62B8jaGS1p58c
 WnAg+7zsTN+xEoJn+tskSSon8BNMWVrl41zP3K4Ged+5j8UEBk62GB8Orz1qkpwL
 fTh3/+xAvczJeD4zZb1dAm4WnmcQJ4vhg45p07jX6owvnwQAikMFl45aSW54I5o8
 vAxGzFgdsZ2NtExnRNKh3b3DozA8JUE89KckBSZnDtq4rH8Fyy6Wij56Hc6v6Cml
 SUohiNbHX7hsNwit/lxL8wuF97IiA0pQSABobEg3rxfTghTUep51LlaN
 =/m4A
 -----END PGP SIGNATURE-----

Merge tag 'hyperv-next-signed-20220114' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

Pull hyperv updates from Wei Liu:

 - More patches for Hyper-V isolation VM support (Tianyu Lan)

 - Bug fixes and clean-up patches from various people

* tag 'hyperv-next-signed-20220114' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  scsi: storvsc: Fix storvsc_queuecommand() memory leak
  x86/hyperv: Properly deal with empty cpumasks in hyperv_flush_tlb_multi()
  Drivers: hv: vmbus: Initialize request offers message for Isolation VM
  scsi: storvsc: Fix unsigned comparison to zero
  swiotlb: Add CONFIG_HAS_IOMEM check around swiotlb_mem_remap()
  x86/hyperv: Fix definition of hv_ghcb_pg variable
  Drivers: hv: Fix definition of hypercall input & output arg variables
  net: netvsc: Add Isolation VM support for netvsc driver
  scsi: storvsc: Add Isolation VM support for storvsc driver
  hyper-v: Enable swiotlb bounce buffer for Isolation VM
  x86/hyper-v: Add hyperv Isolation VM check in the cc_platform_has()
  swiotlb: Add swiotlb bounce buffer remap function for HV IVM
2022-01-16 15:53:00 +02:00

86 lines
2.1 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>
*/
#include <linux/export.h>
#include <linux/cc_platform.h>
#include <linux/mem_encrypt.h>
#include <asm/mshyperv.h>
#include <asm/processor.h>
static bool __maybe_unused intel_cc_platform_has(enum cc_attr attr)
{
#ifdef CONFIG_INTEL_TDX_GUEST
return false;
#else
return false;
#endif
}
/*
* SME and SEV are very similar but they are not the same, so there are
* times that the kernel will need to distinguish between SME and SEV. The
* cc_platform_has() function is used for this. When a distinction isn't
* needed, the CC_ATTR_MEM_ENCRYPT attribute can be used.
*
* The trampoline code is a good example for this requirement. Before
* paging is activated, SME will access all memory as decrypted, but SEV
* will access all memory as encrypted. So, when APs are being brought
* up under SME the trampoline area cannot be encrypted, whereas under SEV
* the trampoline area must be encrypted.
*/
static bool amd_cc_platform_has(enum cc_attr attr)
{
#ifdef CONFIG_AMD_MEM_ENCRYPT
switch (attr) {
case CC_ATTR_MEM_ENCRYPT:
return sme_me_mask;
case CC_ATTR_HOST_MEM_ENCRYPT:
return sme_me_mask && !(sev_status & MSR_AMD64_SEV_ENABLED);
case CC_ATTR_GUEST_MEM_ENCRYPT:
return sev_status & MSR_AMD64_SEV_ENABLED;
case CC_ATTR_GUEST_STATE_ENCRYPT:
return sev_status & MSR_AMD64_SEV_ES_ENABLED;
/*
* With SEV, the rep string I/O instructions need to be unrolled
* but SEV-ES supports them through the #VC handler.
*/
case CC_ATTR_GUEST_UNROLL_STRING_IO:
return (sev_status & MSR_AMD64_SEV_ENABLED) &&
!(sev_status & MSR_AMD64_SEV_ES_ENABLED);
default:
return false;
}
#else
return false;
#endif
}
static bool hyperv_cc_platform_has(enum cc_attr attr)
{
return attr == CC_ATTR_GUEST_MEM_ENCRYPT;
}
bool cc_platform_has(enum cc_attr attr)
{
if (sme_me_mask)
return amd_cc_platform_has(attr);
if (hv_is_isolation_supported())
return hyperv_cc_platform_has(attr);
return false;
}
EXPORT_SYMBOL_GPL(cc_platform_has);