[PATCH v2 00/12] Implement generic prot_guest_has() helper function

STALE1824d

Revision v2 of 2 in this series.

45 messages, 5 authors, 2021-08-24 · open the first message on its own page

[PATCH v2 00/12] Implement generic prot_guest_has() helper function

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 16:59:54

This patch series provides a generic helper function, prot_guest_has(),
to replace the sme_active(), sev_active(), sev_es_active() and
mem_encrypt_active() functions.

It is expected that as new protected virtualization technologies are
added to the kernel, they can all be covered by a single function call
instead of a collection of specific function calls all called from the
same locations.

The powerpc and s390 patches have been compile tested only. Can the
folks copied on this series verify that nothing breaks for them.

Cc: Andi Kleen <redacted>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Baoquan He <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <redacted>
Cc: Daniel Vetter <redacted>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <redacted>
Cc: David Airlie <redacted>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <redacted>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <redacted>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: VMware Graphics <redacted>
Cc: Will Deacon <will@kernel.org>

---

Patches based on:
  https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git master
  0b52902cd2d9 ("Merge branch 'efi/urgent'")

Changes since v1:
- Move some arch ioremap functions within #ifdef CONFIG_AMD_MEM_ENCRYPT
  in prep for use of prot_guest_has() by TDX.
- Add type includes to the the protected_guest.h header file to prevent
  build errors outside of x86.
- Make amd_prot_guest_has() EXPORT_SYMBOL_GPL
- Use amd_prot_guest_has() in place of checking sme_me_mask in the
  arch/x86/mm/mem_encrypt.c file.

Tom Lendacky (12):
  x86/ioremap: Selectively build arch override encryption functions
  mm: Introduce a function to check for virtualization protection
    features
  x86/sev: Add an x86 version of prot_guest_has()
  powerpc/pseries/svm: Add a powerpc version of prot_guest_has()
  x86/sme: Replace occurrences of sme_active() with prot_guest_has()
  x86/sev: Replace occurrences of sev_active() with prot_guest_has()
  x86/sev: Replace occurrences of sev_es_active() with prot_guest_has()
  treewide: Replace the use of mem_encrypt_active() with
    prot_guest_has()
  mm: Remove the now unused mem_encrypt_active() function
  x86/sev: Remove the now unused mem_encrypt_active() function
  powerpc/pseries/svm: Remove the now unused mem_encrypt_active()
    function
  s390/mm: Remove the now unused mem_encrypt_active() function

 arch/Kconfig                               |  3 ++
 arch/powerpc/include/asm/mem_encrypt.h     |  5 --
 arch/powerpc/include/asm/protected_guest.h | 30 +++++++++++
 arch/powerpc/platforms/pseries/Kconfig     |  1 +
 arch/s390/include/asm/mem_encrypt.h        |  2 -
 arch/x86/Kconfig                           |  1 +
 arch/x86/include/asm/io.h                  |  8 +++
 arch/x86/include/asm/kexec.h               |  2 +-
 arch/x86/include/asm/mem_encrypt.h         | 13 +----
 arch/x86/include/asm/protected_guest.h     | 29 +++++++++++
 arch/x86/kernel/crash_dump_64.c            |  4 +-
 arch/x86/kernel/head64.c                   |  4 +-
 arch/x86/kernel/kvm.c                      |  3 +-
 arch/x86/kernel/kvmclock.c                 |  4 +-
 arch/x86/kernel/machine_kexec_64.c         | 19 +++----
 arch/x86/kernel/pci-swiotlb.c              |  9 ++--
 arch/x86/kernel/relocate_kernel_64.S       |  2 +-
 arch/x86/kernel/sev.c                      |  6 +--
 arch/x86/kvm/svm/svm.c                     |  3 +-
 arch/x86/mm/ioremap.c                      | 18 +++----
 arch/x86/mm/mem_encrypt.c                  | 60 +++++++++++++++-------
 arch/x86/mm/mem_encrypt_identity.c         |  3 +-
 arch/x86/mm/pat/set_memory.c               |  3 +-
 arch/x86/platform/efi/efi_64.c             |  9 ++--
 arch/x86/realmode/init.c                   |  8 +--
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c    |  4 +-
 drivers/gpu/drm/drm_cache.c                |  4 +-
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.c        |  4 +-
 drivers/gpu/drm/vmwgfx/vmwgfx_msg.c        |  6 +--
 drivers/iommu/amd/init.c                   |  7 +--
 drivers/iommu/amd/iommu.c                  |  3 +-
 drivers/iommu/amd/iommu_v2.c               |  3 +-
 drivers/iommu/iommu.c                      |  3 +-
 fs/proc/vmcore.c                           |  6 +--
 include/linux/mem_encrypt.h                |  4 --
 include/linux/protected_guest.h            | 40 +++++++++++++++
 kernel/dma/swiotlb.c                       |  4 +-
 37 files changed, 232 insertions(+), 105 deletions(-)
 create mode 100644 arch/powerpc/include/asm/protected_guest.h
 create mode 100644 arch/x86/include/asm/protected_guest.h
 create mode 100644 include/linux/protected_guest.h

-- 
2.32.0

[PATCH v2 01/12] x86/ioremap: Selectively build arch override encryption functions

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:00:03

In prep for other uses of the prot_guest_has() function besides AMD's
memory encryption support, selectively build the AMD memory encryption
architecture override functions only when CONFIG_AMD_MEM_ENCRYPT=y. These
functions are:
- early_memremap_pgprot_adjust()
- arch_memremap_can_ram_remap()

Additionally, routines that are only invoked by these architecture
override functions can also be conditionally built. These functions are:
- memremap_should_map_decrypted()
- memremap_is_efi_data()
- memremap_is_setup_data()
- early_memremap_is_setup_data()

And finally, phys_mem_access_encrypted() is conditionally built as well,
but requires a static inline version of it when CONFIG_AMD_MEM_ENCRYPT is
not set.

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/io.h | 8 ++++++++
 arch/x86/mm/ioremap.c     | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 841a5d104afa..5c6a4af0b911 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h

@@ -391,6 +391,7 @@ extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size)
 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
 #endif
 
+#ifdef CONFIG_AMD_MEM_ENCRYPT
 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
 					unsigned long size,
 					unsigned long flags);

@@ -398,6 +399,13 @@ extern bool arch_memremap_can_ram_remap(resource_size_t offset,
 
 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
 				      unsigned long size);
+#else
+static inline bool phys_mem_access_encrypted(unsigned long phys_addr,
+					     unsigned long size)
+{
+	return true;
+}
+#endif
 
 /**
  * iosubmit_cmds512 - copy data to single MMIO location, in 512-bit units

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 60ade7dd71bd..ccff76cedd8f 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c

@@ -508,6 +508,7 @@ void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
 	memunmap((void *)((unsigned long)addr & PAGE_MASK));
 }
 
+#ifdef CONFIG_AMD_MEM_ENCRYPT
 /*
  * Examine the physical address to determine if it is an area of memory
  * that should be mapped decrypted.  If the memory is not part of the

@@ -746,7 +747,6 @@ bool phys_mem_access_encrypted(unsigned long phys_addr, unsigned long size)
 	return arch_memremap_can_ram_remap(phys_addr, size, 0);
 }
 
-#ifdef CONFIG_AMD_MEM_ENCRYPT
 /* Remap memory with encryption */
 void __init *early_memremap_encrypted(resource_size_t phys_addr,
 				      unsigned long size)

-- 
2.32.0

[PATCH v2 02/12] mm: Introduce a function to check for virtualization protection features

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:00:15

In prep for other protected virtualization technologies, introduce a
generic helper function, prot_guest_has(), that can be used to check
for specific protection attributes, like memory encryption. This is
intended to eliminate having to add multiple technology-specific checks
to the code (e.g. if (sev_active() || tdx_active())).

Reviewed-by: Joerg Roedel <redacted>
Co-developed-by: Andi Kleen <redacted>
Signed-off-by: Andi Kleen <redacted>
Co-developed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/Kconfig                    |  3 +++
 include/linux/protected_guest.h | 35 +++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 include/linux/protected_guest.h

diff --git a/arch/Kconfig b/arch/Kconfig
index 98db63496bab..bd4f60c581f1 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig

@@ -1231,6 +1231,9 @@ config RELR
 config ARCH_HAS_MEM_ENCRYPT
 	bool
 
+config ARCH_HAS_PROTECTED_GUEST
+	bool
+
 config HAVE_SPARSE_SYSCALL_NR
        bool
        help

diff --git a/include/linux/protected_guest.h b/include/linux/protected_guest.h
new file mode 100644
index 000000000000..43d4dde94793
--- /dev/null
+++ b/include/linux/protected_guest.h

@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _PROTECTED_GUEST_H
+#define _PROTECTED_GUEST_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+
+#define PATTR_MEM_ENCRYPT		0	/* Encrypted memory */
+#define PATTR_HOST_MEM_ENCRYPT		1	/* Host encrypted memory */
+#define PATTR_GUEST_MEM_ENCRYPT		2	/* Guest encrypted memory */
+#define PATTR_GUEST_PROT_STATE		3	/* Guest encrypted state */
+
+#ifdef CONFIG_ARCH_HAS_PROTECTED_GUEST
+
+#include <asm/protected_guest.h>
+
+#else	/* !CONFIG_ARCH_HAS_PROTECTED_GUEST */
+
+static inline bool prot_guest_has(unsigned int attr) { return false; }
+
+#endif	/* CONFIG_ARCH_HAS_PROTECTED_GUEST */
+
+#endif	/* __ASSEMBLY__ */
+
+#endif	/* _PROTECTED_GUEST_H */

-- 
2.32.0

[PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:00:18

Introduce an x86 version of the prot_guest_has() function. This will be
used in the more generic x86 code to replace vendor specific calls like
sev_active(), etc.

While the name suggests this is intended mainly for guests, it will
also be used for host memory encryption checks in place of sme_active().

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Joerg Roedel <redacted>
Co-developed-by: Andi Kleen <redacted>
Signed-off-by: Andi Kleen <redacted>
Co-developed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/Kconfig                       |  1 +
 arch/x86/include/asm/mem_encrypt.h     |  2 ++
 arch/x86/include/asm/protected_guest.h | 29 ++++++++++++++++++++++++++
 arch/x86/mm/mem_encrypt.c              | 25 ++++++++++++++++++++++
 include/linux/protected_guest.h        |  5 +++++
 5 files changed, 62 insertions(+)
 create mode 100644 arch/x86/include/asm/protected_guest.h

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 421fa9e38c60..82e5fb713261 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig

@@ -1514,6 +1514,7 @@ config AMD_MEM_ENCRYPT
 	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
 	select INSTRUCTION_DECODER
 	select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
+	select ARCH_HAS_PROTECTED_GUEST
 	help
 	  Say yes to enable support for the encryption of system memory.
 	  This requires an AMD processor that supports Secure Memory

diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index 9c80c68d75b5..a46d47662772 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h

@@ -53,6 +53,7 @@ void __init sev_es_init_vc_handling(void);
 bool sme_active(void);
 bool sev_active(void);
 bool sev_es_active(void);
+bool amd_prot_guest_has(unsigned int attr);
 
 #define __bss_decrypted __section(".bss..decrypted")

@@ -78,6 +79,7 @@ static inline void sev_es_init_vc_handling(void) { }
 static inline bool sme_active(void) { return false; }
 static inline bool sev_active(void) { return false; }
 static inline bool sev_es_active(void) { return false; }
+static inline bool amd_prot_guest_has(unsigned int attr) { return false; }
 
 static inline int __init
 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }

diff --git a/arch/x86/include/asm/protected_guest.h b/arch/x86/include/asm/protected_guest.h
new file mode 100644
index 000000000000..51e4eefd9542
--- /dev/null
+++ b/arch/x86/include/asm/protected_guest.h

@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _X86_PROTECTED_GUEST_H
+#define _X86_PROTECTED_GUEST_H
+
+#include <linux/mem_encrypt.h>
+
+#ifndef __ASSEMBLY__
+
+static inline bool prot_guest_has(unsigned int attr)
+{
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+	if (sme_me_mask)
+		return amd_prot_guest_has(attr);
+#endif
+
+	return false;
+}
+
+#endif	/* __ASSEMBLY__ */
+
+#endif	/* _X86_PROTECTED_GUEST_H */

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index ff08dc463634..edc67ddf065d 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -20,6 +20,7 @@
 #include <linux/bitops.h>
 #include <linux/dma-mapping.h>
 #include <linux/virtio_config.h>
+#include <linux/protected_guest.h>
 
 #include <asm/tlbflush.h>
 #include <asm/fixmap.h>

@@ -389,6 +390,30 @@ bool noinstr sev_es_active(void)
 	return sev_status & MSR_AMD64_SEV_ES_ENABLED;
 }
 
+bool amd_prot_guest_has(unsigned int attr)
+{
+	switch (attr) {
+	case PATTR_MEM_ENCRYPT:
+		return sme_me_mask != 0;
+
+	case PATTR_SME:
+	case PATTR_HOST_MEM_ENCRYPT:
+		return sme_active();
+
+	case PATTR_SEV:
+	case PATTR_GUEST_MEM_ENCRYPT:
+		return sev_active();
+
+	case PATTR_SEV_ES:
+	case PATTR_GUEST_PROT_STATE:
+		return sev_es_active();
+
+	default:
+		return false;
+	}
+}
+EXPORT_SYMBOL_GPL(amd_prot_guest_has);
+
 /* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */
 bool force_dma_unencrypted(struct device *dev)
 {

diff --git a/include/linux/protected_guest.h b/include/linux/protected_guest.h
index 43d4dde94793..5ddef1b6a2ea 100644
--- a/include/linux/protected_guest.h
+++ b/include/linux/protected_guest.h

@@ -20,6 +20,11 @@
 #define PATTR_GUEST_MEM_ENCRYPT		2	/* Guest encrypted memory */
 #define PATTR_GUEST_PROT_STATE		3	/* Guest encrypted state */
 
+/* 0x800 - 0x8ff reserved for AMD */
+#define PATTR_SME			0x800
+#define PATTR_SEV			0x801
+#define PATTR_SEV_ES			0x802
+
 #ifdef CONFIG_ARCH_HAS_PROTECTED_GUEST
 
 #include <asm/protected_guest.h>

-- 
2.32.0

[PATCH v2 04/12] powerpc/pseries/svm: Add a powerpc version of prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:00:39

Introduce a powerpc version of the prot_guest_has() function. This will
be used to replace the powerpc mem_encrypt_active() implementation, so
the implementation will initially only support the PATTR_MEM_ENCRYPT
attribute.

Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/powerpc/include/asm/protected_guest.h | 30 ++++++++++++++++++++++
 arch/powerpc/platforms/pseries/Kconfig     |  1 +
 2 files changed, 31 insertions(+)
 create mode 100644 arch/powerpc/include/asm/protected_guest.h

diff --git a/arch/powerpc/include/asm/protected_guest.h b/arch/powerpc/include/asm/protected_guest.h
new file mode 100644
index 000000000000..ce55c2c7e534
--- /dev/null
+++ b/arch/powerpc/include/asm/protected_guest.h

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _POWERPC_PROTECTED_GUEST_H
+#define _POWERPC_PROTECTED_GUEST_H
+
+#include <asm/svm.h>
+
+#ifndef __ASSEMBLY__
+
+static inline bool prot_guest_has(unsigned int attr)
+{
+	switch (attr) {
+	case PATTR_MEM_ENCRYPT:
+		return is_secure_guest();
+
+	default:
+		return false;
+	}
+}
+
+#endif	/* __ASSEMBLY__ */
+
+#endif	/* _POWERPC_PROTECTED_GUEST_H */

diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index 5e037df2a3a1..8ce5417d6feb 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig

@@ -159,6 +159,7 @@ config PPC_SVM
 	select SWIOTLB
 	select ARCH_HAS_MEM_ENCRYPT
 	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
+	select ARCH_HAS_PROTECTED_GUEST
 	help
 	 There are certain POWER platforms which support secure guests using
 	 the Protected Execution Facility, with the help of an Ultravisor

-- 
2.32.0

[PATCH v2 05/12] x86/sme: Replace occurrences of sme_active() with prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:00:45

Replace occurrences of sme_active() with the more generic prot_guest_has()
using PATTR_HOST_MEM_ENCRYPT, except for in arch/x86/mm/mem_encrypt*.c
where PATTR_SME will be used. If future support is added for other memory
encryption technologies, the use of PATTR_HOST_MEM_ENCRYPT can be
updated, as required, to use PATTR_SME.

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Joerg Roedel <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/kexec.h         |  2 +-
 arch/x86/include/asm/mem_encrypt.h   |  2 --
 arch/x86/kernel/machine_kexec_64.c   |  3 ++-
 arch/x86/kernel/pci-swiotlb.c        |  9 ++++-----
 arch/x86/kernel/relocate_kernel_64.S |  2 +-
 arch/x86/mm/ioremap.c                |  6 +++---
 arch/x86/mm/mem_encrypt.c            | 10 +++++-----
 arch/x86/mm/mem_encrypt_identity.c   |  3 ++-
 arch/x86/realmode/init.c             |  5 +++--
 drivers/iommu/amd/init.c             |  7 ++++---
 10 files changed, 25 insertions(+), 24 deletions(-)

diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
index 0a6e34b07017..11b7c06e2828 100644
--- a/arch/x86/include/asm/kexec.h
+++ b/arch/x86/include/asm/kexec.h

@@ -129,7 +129,7 @@ relocate_kernel(unsigned long indirection_page,
 		unsigned long page_list,
 		unsigned long start_address,
 		unsigned int preserve_context,
-		unsigned int sme_active);
+		unsigned int host_mem_enc_active);
 #endif
 
 #define ARCH_HAS_KIMAGE_ARCH

diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index a46d47662772..956338406cec 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h

@@ -50,7 +50,6 @@ void __init mem_encrypt_free_decrypted_mem(void);
 void __init mem_encrypt_init(void);
 
 void __init sev_es_init_vc_handling(void);
-bool sme_active(void);
 bool sev_active(void);
 bool sev_es_active(void);
 bool amd_prot_guest_has(unsigned int attr);

@@ -76,7 +75,6 @@ static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
 static inline void __init sme_enable(struct boot_params *bp) { }
 
 static inline void sev_es_init_vc_handling(void) { }
-static inline bool sme_active(void) { return false; }
 static inline bool sev_active(void) { return false; }
 static inline bool sev_es_active(void) { return false; }
 static inline bool amd_prot_guest_has(unsigned int attr) { return false; }

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 131f30fdcfbd..8e7b517ad738 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c

@@ -17,6 +17,7 @@
 #include <linux/suspend.h>
 #include <linux/vmalloc.h>
 #include <linux/efi.h>
+#include <linux/protected_guest.h>
 
 #include <asm/init.h>
 #include <asm/tlbflush.h>

@@ -358,7 +359,7 @@ void machine_kexec(struct kimage *image)
 				       (unsigned long)page_list,
 				       image->start,
 				       image->preserve_context,
-				       sme_active());
+				       prot_guest_has(PATTR_HOST_MEM_ENCRYPT));
 
 #ifdef CONFIG_KEXEC_JUMP
 	if (image->preserve_context)

diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
index c2cfa5e7c152..bd9a9cfbc9a2 100644
--- a/arch/x86/kernel/pci-swiotlb.c
+++ b/arch/x86/kernel/pci-swiotlb.c

@@ -6,7 +6,7 @@
 #include <linux/swiotlb.h>
 #include <linux/memblock.h>
 #include <linux/dma-direct.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 
 #include <asm/iommu.h>
 #include <asm/swiotlb.h>

@@ -45,11 +45,10 @@ int __init pci_swiotlb_detect_4gb(void)
 		swiotlb = 1;
 
 	/*
-	 * If SME is active then swiotlb will be set to 1 so that bounce
-	 * buffers are allocated and used for devices that do not support
-	 * the addressing range required for the encryption mask.
+	 * Set swiotlb to 1 so that bounce buffers are allocated and used for
+	 * devices that can't support DMA to encrypted memory.
 	 */
-	if (sme_active())
+	if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		swiotlb = 1;
 
 	return swiotlb;

diff --git a/arch/x86/kernel/relocate_kernel_64.S b/arch/x86/kernel/relocate_kernel_64.S
index c53271aebb64..c8fe74a28143 100644
--- a/arch/x86/kernel/relocate_kernel_64.S
+++ b/arch/x86/kernel/relocate_kernel_64.S

@@ -47,7 +47,7 @@ SYM_CODE_START_NOALIGN(relocate_kernel)
 	 * %rsi page_list
 	 * %rdx start address
 	 * %rcx preserve_context
-	 * %r8  sme_active
+	 * %r8  host_mem_enc_active
 	 */
 
 	/* Save the CPU context, used for jumping back */

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index ccff76cedd8f..583afd54c7e1 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c

@@ -14,7 +14,7 @@
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
 #include <linux/mmiotrace.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <linux/efi.h>
 #include <linux/pgtable.h>

@@ -703,7 +703,7 @@ bool arch_memremap_can_ram_remap(resource_size_t phys_addr, unsigned long size,
 	if (flags & MEMREMAP_DEC)
 		return false;
 
-	if (sme_active()) {
+	if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT)) {
 		if (memremap_is_setup_data(phys_addr, size) ||
 		    memremap_is_efi_data(phys_addr, size))
 			return false;

@@ -729,7 +729,7 @@ pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
 
 	encrypted_prot = true;
 
-	if (sme_active()) {
+	if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT)) {
 		if (early_memremap_is_setup_data(phys_addr, size) ||
 		    memremap_is_efi_data(phys_addr, size))
 			encrypted_prot = false;

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index edc67ddf065d..5635ca9a1fbe 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -144,7 +144,7 @@ void __init sme_unmap_bootdata(char *real_mode_data)
 	struct boot_params *boot_data;
 	unsigned long cmdline_paddr;
 
-	if (!sme_active())
+	if (!amd_prot_guest_has(PATTR_SME))
 		return;
 
 	/* Get the command line address before unmapping the real_mode_data */

@@ -164,7 +164,7 @@ void __init sme_map_bootdata(char *real_mode_data)
 	struct boot_params *boot_data;
 	unsigned long cmdline_paddr;
 
-	if (!sme_active())
+	if (!amd_prot_guest_has(PATTR_SME))
 		return;
 
 	__sme_early_map_unmap_mem(real_mode_data, sizeof(boot_params), true);

@@ -378,7 +378,7 @@ bool sev_active(void)
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }
 
-bool sme_active(void)
+static bool sme_active(void)
 {
 	return sme_me_mask && !sev_active();
 }

@@ -428,7 +428,7 @@ bool force_dma_unencrypted(struct device *dev)
 	 * device does not support DMA to addresses that include the
 	 * encryption mask.
 	 */
-	if (sme_active()) {
+	if (amd_prot_guest_has(PATTR_SME)) {
 		u64 dma_enc_mask = DMA_BIT_MASK(__ffs64(sme_me_mask));
 		u64 dma_dev_mask = min_not_zero(dev->coherent_dma_mask,
 						dev->bus_dma_limit);

@@ -469,7 +469,7 @@ static void print_mem_encrypt_feature_info(void)
 	pr_info("AMD Memory Encryption Features active:");
 
 	/* Secure Memory Encryption */
-	if (sme_active()) {
+	if (amd_prot_guest_has(PATTR_SME)) {
 		/*
 		 * SME is mutually exclusive with any of the SEV
 		 * features below.

diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c
index 470b20208430..088c8ab7dcc1 100644
--- a/arch/x86/mm/mem_encrypt_identity.c
+++ b/arch/x86/mm/mem_encrypt_identity.c

@@ -30,6 +30,7 @@
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 
 #include <asm/setup.h>
 #include <asm/sections.h>

@@ -287,7 +288,7 @@ void __init sme_encrypt_kernel(struct boot_params *bp)
 	unsigned long pgtable_area_len;
 	unsigned long decrypted_base;
 
-	if (!sme_active())
+	if (!prot_guest_has(PATTR_SME))
 		return;
 
 	/*

diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
index 6534c92d0f83..2109ae569c67 100644
--- a/arch/x86/realmode/init.c
+++ b/arch/x86/realmode/init.c

@@ -3,6 +3,7 @@
 #include <linux/slab.h>
 #include <linux/memblock.h>
 #include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <linux/pgtable.h>
 
 #include <asm/set_memory.h>

@@ -44,7 +45,7 @@ void __init reserve_real_mode(void)
 static void sme_sev_setup_real_mode(struct trampoline_header *th)
 {
 #ifdef CONFIG_AMD_MEM_ENCRYPT
-	if (sme_active())
+	if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		th->flags |= TH_FLAGS_SME_ACTIVE;
 
 	if (sev_es_active()) {

@@ -81,7 +82,7 @@ static void __init setup_real_mode(void)
 	 * decrypted memory in order to bring up other processors
 	 * successfully. This is not needed for SEV.
 	 */
-	if (sme_active())
+	if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		set_memory_decrypted((unsigned long)base, size >> PAGE_SHIFT);
 
 	memcpy(base, real_mode_blob, size);

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 46280e6e1535..05e770e3e631 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c

@@ -20,7 +20,7 @@
 #include <linux/amd-iommu.h>
 #include <linux/export.h>
 #include <linux/kmemleak.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <asm/pci-direct.h>
 #include <asm/iommu.h>
 #include <asm/apic.h>

@@ -965,7 +965,7 @@ static bool copy_device_table(void)
 		pr_err("The address of old device table is above 4G, not trustworthy!\n");
 		return false;
 	}
-	old_devtb = (sme_active() && is_kdump_kernel())
+	old_devtb = (prot_guest_has(PATTR_HOST_MEM_ENCRYPT) && is_kdump_kernel())
 		    ? (__force void *)ioremap_encrypted(old_devtb_phys,
 							dev_table_size)
 		    : memremap(old_devtb_phys, dev_table_size, MEMREMAP_WB);

@@ -3022,7 +3022,8 @@ static int __init amd_iommu_init(void)
 
 static bool amd_iommu_sme_check(void)
 {
-	if (!sme_active() || (boot_cpu_data.x86 != 0x17))
+	if (!prot_guest_has(PATTR_HOST_MEM_ENCRYPT) ||
+	    (boot_cpu_data.x86 != 0x17))
 		return true;
 
 	/* For Fam17h, a specific level of support is required */

-- 
2.32.0

[PATCH v2 06/12] x86/sev: Replace occurrences of sev_active() with prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:00:51

Replace occurrences of sev_active() with the more generic prot_guest_has()
using PATTR_GUEST_MEM_ENCRYPT, except for in arch/x86/mm/mem_encrypt*.c
where PATTR_SEV will be used. If future support is added for other memory
encryption technologies, the use of PATTR_GUEST_MEM_ENCRYPT can be
updated, as required, to use PATTR_SEV.

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Joerg Roedel <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/mem_encrypt.h |  2 --
 arch/x86/kernel/crash_dump_64.c    |  4 +++-
 arch/x86/kernel/kvm.c              |  3 ++-
 arch/x86/kernel/kvmclock.c         |  4 ++--
 arch/x86/kernel/machine_kexec_64.c | 16 ++++++++--------
 arch/x86/kvm/svm/svm.c             |  3 ++-
 arch/x86/mm/ioremap.c              |  6 +++---
 arch/x86/mm/mem_encrypt.c          | 15 +++++++--------
 arch/x86/platform/efi/efi_64.c     |  9 +++++----
 9 files changed, 32 insertions(+), 30 deletions(-)

diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index 956338406cec..7e25de37c148 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h

@@ -50,7 +50,6 @@ void __init mem_encrypt_free_decrypted_mem(void);
 void __init mem_encrypt_init(void);
 
 void __init sev_es_init_vc_handling(void);
-bool sev_active(void);
 bool sev_es_active(void);
 bool amd_prot_guest_has(unsigned int attr);

@@ -75,7 +74,6 @@ static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
 static inline void __init sme_enable(struct boot_params *bp) { }
 
 static inline void sev_es_init_vc_handling(void) { }
-static inline bool sev_active(void) { return false; }
 static inline bool sev_es_active(void) { return false; }
 static inline bool amd_prot_guest_has(unsigned int attr) { return false; }

diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c
index 045e82e8945b..0cfe35f03e67 100644
--- a/arch/x86/kernel/crash_dump_64.c
+++ b/arch/x86/kernel/crash_dump_64.c

@@ -10,6 +10,7 @@
 #include <linux/crash_dump.h>
 #include <linux/uaccess.h>
 #include <linux/io.h>
+#include <linux/protected_guest.h>
 
 static ssize_t __copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
 				  unsigned long offset, int userbuf,

@@ -73,5 +74,6 @@ ssize_t copy_oldmem_page_encrypted(unsigned long pfn, char *buf, size_t csize,
 
 ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
 {
-	return read_from_oldmem(buf, count, ppos, 0, sev_active());
+	return read_from_oldmem(buf, count, ppos, 0,
+				prot_guest_has(PATTR_GUEST_MEM_ENCRYPT));
 }

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index a26643dc6bd6..9d08ad2f3faa 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c

@@ -27,6 +27,7 @@
 #include <linux/nmi.h>
 #include <linux/swait.h>
 #include <linux/syscore_ops.h>
+#include <linux/protected_guest.h>
 #include <asm/timer.h>
 #include <asm/cpu.h>
 #include <asm/traps.h>

@@ -418,7 +419,7 @@ static void __init sev_map_percpu_data(void)
 {
 	int cpu;
 
-	if (!sev_active())
+	if (!prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 		return;
 
 	for_each_possible_cpu(cpu) {

diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index ad273e5861c1..f7ba78a23dcd 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c

@@ -16,9 +16,9 @@
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/set_memory.h>
+#include <linux/protected_guest.h>
 
 #include <asm/hypervisor.h>
-#include <asm/mem_encrypt.h>
 #include <asm/x86_init.h>
 #include <asm/kvmclock.h>

@@ -232,7 +232,7 @@ static void __init kvmclock_init_mem(void)
 	 * hvclock is shared between the guest and the hypervisor, must
 	 * be mapped decrypted.
 	 */
-	if (sev_active()) {
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT)) {
 		r = set_memory_decrypted((unsigned long) hvclock_mem,
 					 1UL << order);
 		if (r) {

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 8e7b517ad738..66ff788b79c9 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c

@@ -167,7 +167,7 @@ static int init_transition_pgtable(struct kimage *image, pgd_t *pgd)
 	}
 	pte = pte_offset_kernel(pmd, vaddr);
 
-	if (sev_active())
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 		prot = PAGE_KERNEL_EXEC;
 
 	set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));

@@ -207,7 +207,7 @@ static int init_pgtable(struct kimage *image, unsigned long start_pgtable)
 	level4p = (pgd_t *)__va(start_pgtable);
 	clear_page(level4p);
 
-	if (sev_active()) {
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT)) {
 		info.page_flag   |= _PAGE_ENC;
 		info.kernpg_flag |= _PAGE_ENC;
 	}

@@ -570,12 +570,12 @@ void arch_kexec_unprotect_crashkres(void)
  */
 int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
 {
-	if (sev_active())
+	if (!prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		return 0;
 
 	/*
-	 * If SME is active we need to be sure that kexec pages are
-	 * not encrypted because when we boot to the new kernel the
+	 * If host memory encryption is active we need to be sure that kexec
+	 * pages are not encrypted because when we boot to the new kernel the
 	 * pages won't be accessed encrypted (initially).
 	 */
 	return set_memory_decrypted((unsigned long)vaddr, pages);

@@ -583,12 +583,12 @@ int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
 
 void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages)
 {
-	if (sev_active())
+	if (!prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		return;
 
 	/*
-	 * If SME is active we need to reset the pages back to being
-	 * an encrypted mapping before freeing them.
+	 * If host memory encryption is active we need to reset the pages back
+	 * to being an encrypted mapping before freeing them.
 	 */
 	set_memory_encrypted((unsigned long)vaddr, pages);
 }

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index e8ccab50ebf6..b69f5ac622d5 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c

@@ -25,6 +25,7 @@
 #include <linux/pagemap.h>
 #include <linux/swap.h>
 #include <linux/rwsem.h>
+#include <linux/protected_guest.h>
 
 #include <asm/apic.h>
 #include <asm/perf_event.h>

@@ -457,7 +458,7 @@ static int has_svm(void)
 		return 0;
 	}
 
-	if (sev_active()) {
+	if (prot_guest_has(PATTR_SEV)) {
 		pr_info("KVM is unsupported when running as an SEV guest\n");
 		return 0;
 	}

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 583afd54c7e1..3ed0f28f12af 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c

@@ -92,7 +92,7 @@ static unsigned int __ioremap_check_ram(struct resource *res)
  */
 static unsigned int __ioremap_check_encrypted(struct resource *res)
 {
-	if (!sev_active())
+	if (!prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 		return 0;
 
 	switch (res->desc) {

@@ -112,7 +112,7 @@ static unsigned int __ioremap_check_encrypted(struct resource *res)
  */
 static void __ioremap_check_other(resource_size_t addr, struct ioremap_desc *desc)
 {
-	if (!sev_active())
+	if (!prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 		return;
 
 	if (!IS_ENABLED(CONFIG_EFI))

@@ -556,7 +556,7 @@ static bool memremap_should_map_decrypted(resource_size_t phys_addr,
 	case E820_TYPE_NVS:
 	case E820_TYPE_UNUSABLE:
 		/* For SEV, these areas are encrypted */
-		if (sev_active())
+		if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 			break;
 		fallthrough;

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 5635ca9a1fbe..83bc928f529e 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -194,7 +194,7 @@ void __init sme_early_init(void)
 	for (i = 0; i < ARRAY_SIZE(protection_map); i++)
 		protection_map[i] = pgprot_encrypted(protection_map[i]);
 
-	if (sev_active())
+	if (amd_prot_guest_has(PATTR_SEV))
 		swiotlb_force = SWIOTLB_FORCE;
 }

@@ -203,7 +203,7 @@ void __init sev_setup_arch(void)
 	phys_addr_t total_mem = memblock_phys_mem_size();
 	unsigned long size;
 
-	if (!sev_active())
+	if (!amd_prot_guest_has(PATTR_SEV))
 		return;
 
 	/*

@@ -373,7 +373,7 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size)
  * up under SME the trampoline area cannot be encrypted, whereas under SEV
  * the trampoline area must be encrypted.
  */
-bool sev_active(void)
+static bool sev_active(void)
 {
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }

@@ -382,7 +382,6 @@ static bool sme_active(void)
 {
 	return sme_me_mask && !sev_active();
 }
-EXPORT_SYMBOL_GPL(sev_active);
 
 /* Needs to be called from non-instrumentable code */
 bool noinstr sev_es_active(void)

@@ -420,7 +419,7 @@ bool force_dma_unencrypted(struct device *dev)
 	/*
 	 * For SEV, all DMA must be to unencrypted addresses.
 	 */
-	if (sev_active())
+	if (amd_prot_guest_has(PATTR_SEV))
 		return true;
 
 	/*

@@ -479,7 +478,7 @@ static void print_mem_encrypt_feature_info(void)
 	}
 
 	/* Secure Encrypted Virtualization */
-	if (sev_active())
+	if (amd_prot_guest_has(PATTR_SEV))
 		pr_cont(" SEV");
 
 	/* Encrypted Register State */

@@ -502,7 +501,7 @@ void __init mem_encrypt_init(void)
 	 * With SEV, we need to unroll the rep string I/O instructions,
 	 * but SEV-ES supports them through the #VC handler.
 	 */
-	if (sev_active() && !sev_es_active())
+	if (amd_prot_guest_has(PATTR_SEV) && !sev_es_active())
 		static_branch_enable(&sev_enable_key);
 
 	print_mem_encrypt_feature_info();

@@ -510,6 +509,6 @@ void __init mem_encrypt_init(void)
 
 int arch_has_restricted_virtio_memory_access(void)
 {
-	return sev_active();
+	return amd_prot_guest_has(PATTR_SEV);
 }
 EXPORT_SYMBOL_GPL(arch_has_restricted_virtio_memory_access);

diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 7515e78ef898..94737fcc1e21 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c

@@ -33,7 +33,7 @@
 #include <linux/reboot.h>
 #include <linux/slab.h>
 #include <linux/ucs2_string.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <linux/sched/task.h>
 
 #include <asm/setup.h>

@@ -284,7 +284,8 @@ static void __init __map_region(efi_memory_desc_t *md, u64 va)
 	if (!(md->attribute & EFI_MEMORY_WB))
 		flags |= _PAGE_PCD;
 
-	if (sev_active() && md->type != EFI_MEMORY_MAPPED_IO)
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT) &&
+	    md->type != EFI_MEMORY_MAPPED_IO)
 		flags |= _PAGE_ENC;
 
 	pfn = md->phys_addr >> PAGE_SHIFT;

@@ -390,7 +391,7 @@ static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *m
 	if (!(md->attribute & EFI_MEMORY_RO))
 		pf |= _PAGE_RW;
 
-	if (sev_active())
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 		pf |= _PAGE_ENC;
 
 	return efi_update_mappings(md, pf);

@@ -438,7 +439,7 @@ void __init efi_runtime_update_mappings(void)
 			(md->type != EFI_RUNTIME_SERVICES_CODE))
 			pf |= _PAGE_RW;
 
-		if (sev_active())
+		if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 			pf |= _PAGE_ENC;
 
 		efi_update_mappings(md, pf);

-- 
2.32.0

[PATCH v2 07/12] x86/sev: Replace occurrences of sev_es_active() with prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:00:56

Replace occurrences of sev_es_active() with the more generic
prot_guest_has() using PATTR_GUEST_PROT_STATE, except for in
arch/x86/kernel/sev*.c and arch/x86/mm/mem_encrypt*.c where PATTR_SEV_ES
will be used. If future support is added for other memory encyrption
techonologies, the use of PATTR_GUEST_PROT_STATE can be updated, as
required, to specifically use PATTR_SEV_ES.

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/mem_encrypt.h | 2 --
 arch/x86/kernel/sev.c              | 6 +++---
 arch/x86/mm/mem_encrypt.c          | 7 +++----
 arch/x86/realmode/init.c           | 3 +--
 4 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index 7e25de37c148..797146e0cd6b 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h

@@ -50,7 +50,6 @@ void __init mem_encrypt_free_decrypted_mem(void);
 void __init mem_encrypt_init(void);
 
 void __init sev_es_init_vc_handling(void);
-bool sev_es_active(void);
 bool amd_prot_guest_has(unsigned int attr);
 
 #define __bss_decrypted __section(".bss..decrypted")

@@ -74,7 +73,6 @@ static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
 static inline void __init sme_enable(struct boot_params *bp) { }
 
 static inline void sev_es_init_vc_handling(void) { }
-static inline bool sev_es_active(void) { return false; }
 static inline bool amd_prot_guest_has(unsigned int attr) { return false; }
 
 static inline int __init

diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index a6895e440bc3..66a4ab9d95d7 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c

@@ -11,7 +11,7 @@
 
 #include <linux/sched/debug.h>	/* For show_regs() */
 #include <linux/percpu-defs.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <linux/printk.h>
 #include <linux/mm_types.h>
 #include <linux/set_memory.h>

@@ -615,7 +615,7 @@ int __init sev_es_efi_map_ghcbs(pgd_t *pgd)
 	int cpu;
 	u64 pfn;
 
-	if (!sev_es_active())
+	if (!prot_guest_has(PATTR_SEV_ES))
 		return 0;
 
 	pflags = _PAGE_NX | _PAGE_RW;

@@ -774,7 +774,7 @@ void __init sev_es_init_vc_handling(void)
 
 	BUILD_BUG_ON(offsetof(struct sev_es_runtime_data, ghcb_page) % PAGE_SIZE);
 
-	if (!sev_es_active())
+	if (!prot_guest_has(PATTR_SEV_ES))
 		return;
 
 	if (!sev_es_check_cpu_features())

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 83bc928f529e..38dfa84b77a1 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -383,8 +383,7 @@ static bool sme_active(void)
 	return sme_me_mask && !sev_active();
 }
 
-/* Needs to be called from non-instrumentable code */
-bool noinstr sev_es_active(void)
+static bool sev_es_active(void)
 {
 	return sev_status & MSR_AMD64_SEV_ES_ENABLED;
 }

@@ -482,7 +481,7 @@ static void print_mem_encrypt_feature_info(void)
 		pr_cont(" SEV");
 
 	/* Encrypted Register State */
-	if (sev_es_active())
+	if (amd_prot_guest_has(PATTR_SEV_ES))
 		pr_cont(" SEV-ES");
 
 	pr_cont("\n");

@@ -501,7 +500,7 @@ void __init mem_encrypt_init(void)
 	 * With SEV, we need to unroll the rep string I/O instructions,
 	 * but SEV-ES supports them through the #VC handler.
 	 */
-	if (amd_prot_guest_has(PATTR_SEV) && !sev_es_active())
+	if (amd_prot_guest_has(PATTR_SEV) && !amd_prot_guest_has(PATTR_SEV_ES))
 		static_branch_enable(&sev_enable_key);
 
 	print_mem_encrypt_feature_info();

diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
index 2109ae569c67..7711d0071f41 100644
--- a/arch/x86/realmode/init.c
+++ b/arch/x86/realmode/init.c

@@ -2,7 +2,6 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/memblock.h>
-#include <linux/mem_encrypt.h>
 #include <linux/protected_guest.h>
 #include <linux/pgtable.h>

@@ -48,7 +47,7 @@ static void sme_sev_setup_real_mode(struct trampoline_header *th)
 	if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		th->flags |= TH_FLAGS_SME_ACTIVE;
 
-	if (sev_es_active()) {
+	if (prot_guest_has(PATTR_GUEST_PROT_STATE)) {
 		/*
 		 * Skip the call to verify_cpu() in secondary_startup_64 as it
 		 * will cause #VC exceptions when the AP can't handle them yet.

-- 
2.32.0

[PATCH v2 08/12] treewide: Replace the use of mem_encrypt_active() with prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:01:13

Replace occurrences of mem_encrypt_active() with calls to prot_guest_has()
with the PATTR_MEM_ENCRYPT attribute.

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Airlie <redacted>
Cc: Daniel Vetter <redacted>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: VMware Graphics <redacted>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Will Deacon <will@kernel.org>
Cc: Dave Young <redacted>
Cc: Baoquan He <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/kernel/head64.c                | 4 ++--
 arch/x86/mm/ioremap.c                   | 4 ++--
 arch/x86/mm/mem_encrypt.c               | 5 ++---
 arch/x86/mm/pat/set_memory.c            | 3 ++-
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 4 +++-
 drivers/gpu/drm/drm_cache.c             | 4 ++--
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.c     | 4 ++--
 drivers/gpu/drm/vmwgfx/vmwgfx_msg.c     | 6 +++---
 drivers/iommu/amd/iommu.c               | 3 ++-
 drivers/iommu/amd/iommu_v2.c            | 3 ++-
 drivers/iommu/iommu.c                   | 3 ++-
 fs/proc/vmcore.c                        | 6 +++---
 kernel/dma/swiotlb.c                    | 4 ++--
 13 files changed, 29 insertions(+), 24 deletions(-)

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index de01903c3735..cafed6456d45 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c

@@ -19,7 +19,7 @@
 #include <linux/start_kernel.h>
 #include <linux/io.h>
 #include <linux/memblock.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <linux/pgtable.h>
 
 #include <asm/processor.h>

@@ -285,7 +285,7 @@ unsigned long __head __startup_64(unsigned long physaddr,
 	 * there is no need to zero it after changing the memory encryption
 	 * attribute.
 	 */
-	if (mem_encrypt_active()) {
+	if (prot_guest_has(PATTR_MEM_ENCRYPT)) {
 		vaddr = (unsigned long)__start_bss_decrypted;
 		vaddr_end = (unsigned long)__end_bss_decrypted;
 		for (; vaddr < vaddr_end; vaddr += PMD_SIZE) {

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 3ed0f28f12af..7f012fc1b600 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c

@@ -694,7 +694,7 @@ static bool __init early_memremap_is_setup_data(resource_size_t phys_addr,
 bool arch_memremap_can_ram_remap(resource_size_t phys_addr, unsigned long size,
 				 unsigned long flags)
 {
-	if (!mem_encrypt_active())
+	if (!prot_guest_has(PATTR_MEM_ENCRYPT))
 		return true;
 
 	if (flags & MEMREMAP_ENC)

@@ -724,7 +724,7 @@ pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
 {
 	bool encrypted_prot;
 
-	if (!mem_encrypt_active())
+	if (!prot_guest_has(PATTR_MEM_ENCRYPT))
 		return prot;
 
 	encrypted_prot = true;

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 38dfa84b77a1..69aed9935b5e 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -364,8 +364,7 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size)
 /*
  * 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
- * sme_active() and sev_active() functions are used for this.  When a
- * distinction isn't needed, the mem_encrypt_active() function can be used.
+ * sme_active() and sev_active() functions are used for this.
  *
  * The trampoline code is a good example for this requirement.  Before
  * paging is activated, SME will access all memory as decrypted, but SEV

@@ -451,7 +450,7 @@ void __init mem_encrypt_free_decrypted_mem(void)
 	 * The unused memory range was mapped decrypted, change the encryption
 	 * attribute from decrypted to encrypted before freeing it.
 	 */
-	if (mem_encrypt_active()) {
+	if (amd_prot_guest_has(PATTR_MEM_ENCRYPT)) {
 		r = set_memory_encrypted(vaddr, npages);
 		if (r) {
 			pr_warn("failed to free unused decrypted pages\n");

diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index ad8a5c586a35..6925f2bb4be1 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c

@@ -18,6 +18,7 @@
 #include <linux/libnvdimm.h>
 #include <linux/vmstat.h>
 #include <linux/kernel.h>
+#include <linux/protected_guest.h>
 
 #include <asm/e820/api.h>
 #include <asm/processor.h>

@@ -1986,7 +1987,7 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
 	int ret;
 
 	/* Nothing to do if memory encryption is not active */
-	if (!mem_encrypt_active())
+	if (!prot_guest_has(PATTR_MEM_ENCRYPT))
 		return 0;
 
 	/* Should not be working on unaligned addresses */

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 971c5b8e75dc..21c1e3056070 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c

@@ -38,6 +38,7 @@
 #include <drm/drm_probe_helper.h>
 #include <linux/mmu_notifier.h>
 #include <linux/suspend.h>
+#include <linux/protected_guest.h>
 
 #include "amdgpu.h"
 #include "amdgpu_irq.h"

@@ -1250,7 +1251,8 @@ static int amdgpu_pci_probe(struct pci_dev *pdev,
 	 * however, SME requires an indirect IOMMU mapping because the encryption
 	 * bit is beyond the DMA mask of the chip.
 	 */
-	if (mem_encrypt_active() && ((flags & AMD_ASIC_MASK) == CHIP_RAVEN)) {
+	if (prot_guest_has(PATTR_MEM_ENCRYPT) &&
+	    ((flags & AMD_ASIC_MASK) == CHIP_RAVEN)) {
 		dev_info(&pdev->dev,
 			 "SME is not compatible with RAVEN\n");
 		return -ENOTSUPP;

diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c
index 546599f19a93..4d01d44012fd 100644
--- a/drivers/gpu/drm/drm_cache.c
+++ b/drivers/gpu/drm/drm_cache.c

@@ -31,7 +31,7 @@
 #include <linux/dma-buf-map.h>
 #include <linux/export.h>
 #include <linux/highmem.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <xen/xen.h>
 
 #include <drm/drm_cache.h>

@@ -204,7 +204,7 @@ bool drm_need_swiotlb(int dma_bits)
 	 * Enforce dma_alloc_coherent when memory encryption is active as well
 	 * for the same reasons as for Xen paravirtual hosts.
 	 */
-	if (mem_encrypt_active())
+	if (prot_guest_has(PATTR_MEM_ENCRYPT))
 		return true;
 
 	for (tmp = iomem_resource.child; tmp; tmp = tmp->sibling)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index 45aeeca9b8f6..498f52ba08ea 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c

@@ -29,7 +29,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/module.h>
 #include <linux/pci.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 
 #include <drm/drm_aperture.h>
 #include <drm/drm_drv.h>

@@ -633,7 +633,7 @@ static int vmw_dma_select_mode(struct vmw_private *dev_priv)
 		[vmw_dma_map_bind] = "Giving up DMA mappings early."};
 
 	/* TTM currently doesn't fully support SEV encryption. */
-	if (mem_encrypt_active())
+	if (prot_guest_has(PATTR_MEM_ENCRYPT))
 		return -EINVAL;
 
 	if (vmw_force_coherent)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
index 3d08f5700bdb..0c70573d3dce 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c

@@ -28,7 +28,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/slab.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 
 #include <asm/hypervisor.h>

@@ -153,7 +153,7 @@ static unsigned long vmw_port_hb_out(struct rpc_channel *channel,
 	unsigned long msg_len = strlen(msg);
 
 	/* HB port can't access encrypted memory. */
-	if (hb && !mem_encrypt_active()) {
+	if (hb && !prot_guest_has(PATTR_MEM_ENCRYPT)) {
 		unsigned long bp = channel->cookie_high;
 
 		si = (uintptr_t) msg;

@@ -208,7 +208,7 @@ static unsigned long vmw_port_hb_in(struct rpc_channel *channel, char *reply,
 	unsigned long si, di, eax, ebx, ecx, edx;
 
 	/* HB port can't access encrypted memory */
-	if (hb && !mem_encrypt_active()) {
+	if (hb && !prot_guest_has(PATTR_MEM_ENCRYPT)) {
 		unsigned long bp = channel->cookie_low;
 
 		si = channel->cookie_high;

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 811a49a95d04..def63a8deab4 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c

@@ -31,6 +31,7 @@
 #include <linux/irqdomain.h>
 #include <linux/percpu.h>
 #include <linux/io-pgtable.h>
+#include <linux/protected_guest.h>
 #include <asm/irq_remapping.h>
 #include <asm/io_apic.h>
 #include <asm/apic.h>

@@ -2178,7 +2179,7 @@ static int amd_iommu_def_domain_type(struct device *dev)
 	 * active, because some of those devices (AMD GPUs) don't have the
 	 * encryption bit in their DMA-mask and require remapping.
 	 */
-	if (!mem_encrypt_active() && dev_data->iommu_v2)
+	if (!prot_guest_has(PATTR_MEM_ENCRYPT) && dev_data->iommu_v2)
 		return IOMMU_DOMAIN_IDENTITY;
 
 	return 0;

diff --git a/drivers/iommu/amd/iommu_v2.c b/drivers/iommu/amd/iommu_v2.c
index f8d4ad421e07..ac359bc98523 100644
--- a/drivers/iommu/amd/iommu_v2.c
+++ b/drivers/iommu/amd/iommu_v2.c

@@ -16,6 +16,7 @@
 #include <linux/wait.h>
 #include <linux/pci.h>
 #include <linux/gfp.h>
+#include <linux/protected_guest.h>
 
 #include "amd_iommu.h"

@@ -741,7 +742,7 @@ int amd_iommu_init_device(struct pci_dev *pdev, int pasids)
 	 * When memory encryption is active the device is likely not in a
 	 * direct-mapped domain. Forbid using IOMMUv2 functionality for now.
 	 */
-	if (mem_encrypt_active())
+	if (prot_guest_has(PATTR_MEM_ENCRYPT))
 		return -ENODEV;
 
 	if (!amd_iommu_v2_supported())

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 5419c4b9f27a..ddbedb1b5b6b 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c

@@ -23,6 +23,7 @@
 #include <linux/property.h>
 #include <linux/fsl/mc.h>
 #include <linux/module.h>
+#include <linux/protected_guest.h>
 #include <trace/events/iommu.h>
 
 static struct kset *iommu_group_kset;

@@ -127,7 +128,7 @@ static int __init iommu_subsys_init(void)
 		else
 			iommu_set_default_translated(false);
 
-		if (iommu_default_passthrough() && mem_encrypt_active()) {
+		if (iommu_default_passthrough() && prot_guest_has(PATTR_MEM_ENCRYPT)) {
 			pr_info("Memory encryption detected - Disabling default IOMMU Passthrough\n");
 			iommu_set_default_translated(false);
 		}

diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 9a15334da208..b466f543dc00 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c

@@ -26,7 +26,7 @@
 #include <linux/vmalloc.h>
 #include <linux/pagemap.h>
 #include <linux/uaccess.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <asm/io.h>
 #include "internal.h"

@@ -177,7 +177,7 @@ ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos)
  */
 ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos)
 {
-	return read_from_oldmem(buf, count, ppos, 0, mem_encrypt_active());
+	return read_from_oldmem(buf, count, ppos, 0, prot_guest_has(PATTR_MEM_ENCRYPT));
 }
 
 /*

@@ -378,7 +378,7 @@ static ssize_t __read_vmcore(char *buffer, size_t buflen, loff_t *fpos,
 					    buflen);
 			start = m->paddr + *fpos - m->offset;
 			tmp = read_from_oldmem(buffer, tsz, &start,
-					       userbuf, mem_encrypt_active());
+					       userbuf, prot_guest_has(PATTR_MEM_ENCRYPT));
 			if (tmp < 0)
 				return tmp;
 			buflen -= tsz;

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index e50df8d8f87e..2e8dee23a624 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c

@@ -34,7 +34,7 @@
 #include <linux/highmem.h>
 #include <linux/gfp.h>
 #include <linux/scatterlist.h>
-#include <linux/mem_encrypt.h>
+#include <linux/protected_guest.h>
 #include <linux/set_memory.h>
 #ifdef CONFIG_DEBUG_FS
 #include <linux/debugfs.h>

@@ -515,7 +515,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
 	if (!mem)
 		panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer");
 
-	if (mem_encrypt_active())
+	if (prot_guest_has(PATTR_MEM_ENCRYPT))
 		pr_warn_once("Memory encryption is active and system is using DMA bounce buffers\n");
 
 	if (mapping_size > alloc_size) {

-- 
2.32.0

[PATCH v2 09/12] mm: Remove the now unused mem_encrypt_active() function

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:01:32

The mem_encrypt_active() function has been replaced by prot_guest_has(),
so remove the implementation.

Reviewed-by: Joerg Roedel <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 include/linux/mem_encrypt.h | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/include/linux/mem_encrypt.h b/include/linux/mem_encrypt.h
index 5c4a18a91f89..ae4526389261 100644
--- a/include/linux/mem_encrypt.h
+++ b/include/linux/mem_encrypt.h

@@ -16,10 +16,6 @@
 
 #include <asm/mem_encrypt.h>
 
-#else	/* !CONFIG_ARCH_HAS_MEM_ENCRYPT */
-
-static inline bool mem_encrypt_active(void) { return false; }
-
 #endif	/* CONFIG_ARCH_HAS_MEM_ENCRYPT */
 
 #ifdef CONFIG_AMD_MEM_ENCRYPT

-- 
2.32.0

[PATCH v2 10/12] x86/sev: Remove the now unused mem_encrypt_active() function

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:01:46

The mem_encrypt_active() function has been replaced by prot_guest_has(),
so remove the implementation.

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Reviewed-by: Joerg Roedel <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/mem_encrypt.h | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index 797146e0cd6b..94c089e9ea69 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h

@@ -97,11 +97,6 @@ static inline void mem_encrypt_free_decrypted_mem(void) { }
 
 extern char __start_bss_decrypted[], __end_bss_decrypted[], __start_bss_decrypted_unused[];
 
-static inline bool mem_encrypt_active(void)
-{
-	return sme_me_mask;
-}
-
 static inline u64 sme_get_me_mask(void)
 {
 	return sme_me_mask;

-- 
2.32.0

[PATCH v2 11/12] powerpc/pseries/svm: Remove the now unused mem_encrypt_active() function

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:01:54

The mem_encrypt_active() function has been replaced by prot_guest_has(),
so remove the implementation.

Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/powerpc/include/asm/mem_encrypt.h | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/arch/powerpc/include/asm/mem_encrypt.h b/arch/powerpc/include/asm/mem_encrypt.h
index ba9dab07c1be..2f26b8fc8d29 100644
--- a/arch/powerpc/include/asm/mem_encrypt.h
+++ b/arch/powerpc/include/asm/mem_encrypt.h

@@ -10,11 +10,6 @@
 
 #include <asm/svm.h>
 
-static inline bool mem_encrypt_active(void)
-{
-	return is_secure_guest();
-}
-
 static inline bool force_dma_unencrypted(struct device *dev)
 {
 	return is_secure_guest();

-- 
2.32.0

[PATCH v2 12/12] s390/mm: Remove the now unused mem_encrypt_active() function

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:01:58

The mem_encrypt_active() function has been replaced by prot_guest_has(),
so remove the implementation. Since the default implementation of the
prot_guest_has() matches the s390 implementation of mem_encrypt_active(),
prot_guest_has() does not need to be implemented in s390 (the config
option ARCH_HAS_PROTECTED_GUEST is not set).

Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/s390/include/asm/mem_encrypt.h | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/s390/include/asm/mem_encrypt.h b/arch/s390/include/asm/mem_encrypt.h
index 2542cbf7e2d1..08a8b96606d7 100644
--- a/arch/s390/include/asm/mem_encrypt.h
+++ b/arch/s390/include/asm/mem_encrypt.h

@@ -4,8 +4,6 @@
 
 #ifndef __ASSEMBLY__
 
-static inline bool mem_encrypt_active(void) { return false; }
-
 int set_memory_encrypted(unsigned long addr, int numpages);
 int set_memory_decrypted(unsigned long addr, int numpages);

-- 
2.32.0

Re: [PATCH v2 02/12] mm: Introduce a function to check for virtualization protection features

From: "Kuppuswamy, Sathyanarayanan" <sathyanarayanan.kuppuswamy@linux.intel.com>
Date: 2021-08-13 17:19:54


On 8/13/21 9:59 AM, Tom Lendacky wrote:

In prep for other protected virtualization technologies, introduce a
generic helper function, prot_guest_has(), that can be used to check
for specific protection attributes, like memory encryption. This is
intended to eliminate having to add multiple technology-specific checks
to the code (e.g. if (sev_active() || tdx_active())).

Reviewed-by: Joerg Roedel<redacted>
Co-developed-by: Andi Kleen<redacted>
Signed-off-by: Andi Kleen<redacted>
Co-developed-by: Kuppuswamy Sathyanarayanan<sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan<sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Tom Lendacky<thomas.lendacky@amd.com>
---
  arch/Kconfig                    |  3 +++
  include/linux/protected_guest.h | 35 +++++++++++++++++++++++++++++++++
  2 files changed, 38 insertions(+)
  create mode 100644 include/linux/protected_guest.h

Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer

Re: [PATCH v2 00/12] Implement generic prot_guest_has() helper function

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-13 17:22:59

On 8/13/21 11:59 AM, Tom Lendacky wrote:

This patch series provides a generic helper function, prot_guest_has(),
to replace the sme_active(), sev_active(), sev_es_active() and
mem_encrypt_active() functions.

It is expected that as new protected virtualization technologies are
added to the kernel, they can all be covered by a single function call
instead of a collection of specific function calls all called from the
same locations.

The powerpc and s390 patches have been compile tested only. Can the
folks copied on this series verify that nothing breaks for them.

There are some patches related to PPC that added new calls to the 
mem_encrypt_active() function that are not yet in the tip tree. After the 
merge window, I'll need to send a v3 with those additional changes before 
this series can be applied.

Thanks,
Tom

Re: [PATCH v2 01/12] x86/ioremap: Selectively build arch override encryption functions

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-14 15:24:36

On Fri, Aug 13, 2021 at 11:59:20AM -0500, Tom Lendacky wrote:

In prep for other uses of the prot_guest_has() function besides AMD's
memory encryption support, selectively build the AMD memory encryption
architecture override functions only when CONFIG_AMD_MEM_ENCRYPT=y. These
functions are:
- early_memremap_pgprot_adjust()
- arch_memremap_can_ram_remap()

Additionally, routines that are only invoked by these architecture
override functions can also be conditionally built. These functions are:
- memremap_should_map_decrypted()
- memremap_is_efi_data()
- memremap_is_setup_data()
- early_memremap_is_setup_data()

And finally, phys_mem_access_encrypted() is conditionally built as well,
but requires a static inline version of it when CONFIG_AMD_MEM_ENCRYPT is
not set.

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/io.h | 8 ++++++++
 arch/x86/mm/ioremap.c     | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

LGTM.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 02/12] mm: Introduce a function to check for virtualization protection features

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-14 18:32:17

On Fri, Aug 13, 2021 at 11:59:21AM -0500, Tom Lendacky wrote:

quoted hunk

In prep for other protected virtualization technologies, introduce a
generic helper function, prot_guest_has(), that can be used to check
for specific protection attributes, like memory encryption. This is
intended to eliminate having to add multiple technology-specific checks
to the code (e.g. if (sev_active() || tdx_active())).

Reviewed-by: Joerg Roedel <redacted>
Co-developed-by: Andi Kleen <redacted>
Signed-off-by: Andi Kleen <redacted>
Co-developed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/Kconfig                    |  3 +++
 include/linux/protected_guest.h | 35 +++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 include/linux/protected_guest.h

diff --git a/arch/Kconfig b/arch/Kconfig
index 98db63496bab..bd4f60c581f1 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig

@@ -1231,6 +1231,9 @@ config RELR
 config ARCH_HAS_MEM_ENCRYPT
 	bool
 
+config ARCH_HAS_PROTECTED_GUEST
+	bool
+
 config HAVE_SPARSE_SYSCALL_NR
        bool
        help

diff --git a/include/linux/protected_guest.h b/include/linux/protected_guest.h
new file mode 100644
index 000000000000..43d4dde94793
--- /dev/null
+++ b/include/linux/protected_guest.h

@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _PROTECTED_GUEST_H
+#define _PROTECTED_GUEST_H
+
+#ifndef __ASSEMBLY__

	   ^^^^^^^^^^^^^

Do you really need that guard? It builds fine without it too. Or
something coming later does need it...?

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 02/12] mm: Introduce a function to check for virtualization protection features

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-14 18:49:32

On 8/14/21 1:32 PM, Borislav Petkov wrote:

On Fri, Aug 13, 2021 at 11:59:21AM -0500, Tom Lendacky wrote:

quoted

diff --git a/include/linux/protected_guest.h b/include/linux/protected_guest.h
new file mode 100644
index 000000000000..43d4dde94793
--- /dev/null
+++ b/include/linux/protected_guest.h

@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _PROTECTED_GUEST_H
+#define _PROTECTED_GUEST_H
+
+#ifndef __ASSEMBLY__

	   ^^^^^^^^^^^^^

Do you really need that guard? It builds fine without it too. Or
something coming later does need it...?

No, I probably did it out of habit. I can remove it in the next version.

Thanks,
Tom

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-14 19:08:41

On Fri, Aug 13, 2021 at 11:59:22AM -0500, Tom Lendacky wrote:

quoted hunk

diff --git a/arch/x86/include/asm/protected_guest.h b/arch/x86/include/asm/protected_guest.h
new file mode 100644
index 000000000000..51e4eefd9542
--- /dev/null
+++ b/arch/x86/include/asm/protected_guest.h

@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _X86_PROTECTED_GUEST_H
+#define _X86_PROTECTED_GUEST_H
+
+#include <linux/mem_encrypt.h>
+
+#ifndef __ASSEMBLY__
+
+static inline bool prot_guest_has(unsigned int attr)
+{
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+	if (sme_me_mask)
+		return amd_prot_guest_has(attr);
+#endif
+
+	return false;
+}
+
+#endif	/* __ASSEMBLY__ */
+
+#endif	/* _X86_PROTECTED_GUEST_H */

I think this can be simplified more, diff ontop below:

- no need for the ifdeffery as amd_prot_guest_has() has versions for
both when CONFIG_AMD_MEM_ENCRYPT is set or not.

- the sme_me_mask check is pushed there too.

- and since this is vendor-specific, I'm checking the vendor bit. Yeah,
yeah, cross-vendor but I don't really believe that.

---

diff --git a/arch/x86/include/asm/protected_guest.h b/arch/x86/include/asm/protected_guest.h
index 51e4eefd9542..8541c76d5da4 100644
--- a/arch/x86/include/asm/protected_guest.h
+++ b/arch/x86/include/asm/protected_guest.h

@@ -12,18 +12,13 @@
 
 #include <linux/mem_encrypt.h>
 
-#ifndef __ASSEMBLY__
-
 static inline bool prot_guest_has(unsigned int attr)
 {
-#ifdef CONFIG_AMD_MEM_ENCRYPT
-	if (sme_me_mask)
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+	    boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
 		return amd_prot_guest_has(attr);
-#endif
 
 	return false;
 }
 
-#endif	/* __ASSEMBLY__ */
-
 #endif	/* _X86_PROTECTED_GUEST_H */

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index edc67ddf065d..5a0442a6f072 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -392,6 +392,9 @@ bool noinstr sev_es_active(void)
 
 bool amd_prot_guest_has(unsigned int attr)
 {
+	if (!sme_me_mask)
+		return false;
+
 	switch (attr) {
 	case PATTR_MEM_ENCRYPT:
 		return sme_me_mask != 0;

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-15 13:55:56

On 8/14/21 2:08 PM, Borislav Petkov wrote:

On Fri, Aug 13, 2021 at 11:59:22AM -0500, Tom Lendacky wrote:

quoted

diff --git a/arch/x86/include/asm/protected_guest.h b/arch/x86/include/asm/protected_guest.h
new file mode 100644
index 000000000000..51e4eefd9542
--- /dev/null
+++ b/arch/x86/include/asm/protected_guest.h

@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _X86_PROTECTED_GUEST_H
+#define _X86_PROTECTED_GUEST_H
+
+#include <linux/mem_encrypt.h>
+
+#ifndef __ASSEMBLY__
+
+static inline bool prot_guest_has(unsigned int attr)
+{
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+	if (sme_me_mask)
+		return amd_prot_guest_has(attr);
+#endif
+
+	return false;
+}
+
+#endif	/* __ASSEMBLY__ */
+
+#endif	/* _X86_PROTECTED_GUEST_H */

I think this can be simplified more, diff ontop below:

- no need for the ifdeffery as amd_prot_guest_has() has versions for
both when CONFIG_AMD_MEM_ENCRYPT is set or not.

Ugh, yeah, not sure why I put that in for this version since I have the 
static inline for when CONFIG_AMD_MEM_ENCRYPT is not set.

- the sme_me_mask check is pushed there too.

- and since this is vendor-specific, I'm checking the vendor bit. Yeah,
yeah, cross-vendor but I don't really believe that.

It's not a cross-vendor thing as opposed to a KVM or other hypervisor 
thing where the family doesn't have to be reported as AMD or HYGON. That's 
why I made the if check be for sme_me_mask. I think that is the safer way 
to go.

Thanks,
Tom

quoted hunk

---

diff --git a/arch/x86/include/asm/protected_guest.h b/arch/x86/include/asm/protected_guest.h
index 51e4eefd9542..8541c76d5da4 100644
--- a/arch/x86/include/asm/protected_guest.h
+++ b/arch/x86/include/asm/protected_guest.h

@@ -12,18 +12,13 @@
  
  #include <linux/mem_encrypt.h>
  
-#ifndef __ASSEMBLY__
-
  static inline bool prot_guest_has(unsigned int attr)
  {
-#ifdef CONFIG_AMD_MEM_ENCRYPT
-	if (sme_me_mask)
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+	    boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
  		return amd_prot_guest_has(attr);
-#endif
  
  	return false;
  }
  
-#endif	/* __ASSEMBLY__ */
-
  #endif	/* _X86_PROTECTED_GUEST_H */

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index edc67ddf065d..5a0442a6f072 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -392,6 +392,9 @@ bool noinstr sev_es_active(void)
  
  bool amd_prot_guest_has(unsigned int attr)
  {
+	if (!sme_me_mask)
+		return false;
+
  	switch (attr) {
  	case PATTR_MEM_ENCRYPT:
  		return sme_me_mask != 0;

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-15 14:38:41

On Sun, Aug 15, 2021 at 08:53:31AM -0500, Tom Lendacky wrote:

It's not a cross-vendor thing as opposed to a KVM or other hypervisor
thing where the family doesn't have to be reported as AMD or HYGON.

What would be the use case? A HV starts a guest which is supposed to be
encrypted using the AMD's confidential guest technology but the HV tells
the guest that it is not running on an AMD SVM HV but something else?

Is that even an actual use case?

Or am I way off?

I know we have talked about this in the past but this still sounds
insane.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 04/12] powerpc/pseries/svm: Add a powerpc version of prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 08:34:56

On Fri, Aug 13, 2021 at 11:59:23AM -0500, Tom Lendacky wrote:

quoted hunk

Introduce a powerpc version of the prot_guest_has() function. This will
be used to replace the powerpc mem_encrypt_active() implementation, so
the implementation will initially only support the PATTR_MEM_ENCRYPT
attribute.

Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/powerpc/include/asm/protected_guest.h | 30 ++++++++++++++++++++++
 arch/powerpc/platforms/pseries/Kconfig     |  1 +
 2 files changed, 31 insertions(+)
 create mode 100644 arch/powerpc/include/asm/protected_guest.h

diff --git a/arch/powerpc/include/asm/protected_guest.h b/arch/powerpc/include/asm/protected_guest.h
new file mode 100644
index 000000000000..ce55c2c7e534
--- /dev/null
+++ b/arch/powerpc/include/asm/protected_guest.h

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _POWERPC_PROTECTED_GUEST_H
+#define _POWERPC_PROTECTED_GUEST_H
+
+#include <asm/svm.h>
+
+#ifndef __ASSEMBLY__

Same thing here. Pls audit the whole set whether those __ASSEMBLY__
guards are really needed and remove them if not.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 05/12] x86/sme: Replace occurrences of sme_active() with prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 09:00:37

On Fri, Aug 13, 2021 at 11:59:24AM -0500, Tom Lendacky wrote:

quoted hunk

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index edc67ddf065d..5635ca9a1fbe 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -144,7 +144,7 @@ void __init sme_unmap_bootdata(char *real_mode_data)
 	struct boot_params *boot_data;
 	unsigned long cmdline_paddr;
 
-	if (!sme_active())
+	if (!amd_prot_guest_has(PATTR_SME))
 		return;
 
 	/* Get the command line address before unmapping the real_mode_data */

@@ -164,7 +164,7 @@ void __init sme_map_bootdata(char *real_mode_data)
 	struct boot_params *boot_data;
 	unsigned long cmdline_paddr;
 
-	if (!sme_active())
+	if (!amd_prot_guest_has(PATTR_SME))
 		return;
 
 	__sme_early_map_unmap_mem(real_mode_data, sizeof(boot_params), true);

@@ -378,7 +378,7 @@ bool sev_active(void)
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }
 
-bool sme_active(void)
+static bool sme_active(void)

Just get rid of it altogether. Also, there's an

EXPORT_SYMBOL_GPL(sev_active);

which needs to go under the actual function. Here's a diff ontop:

---

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 5635ca9a1fbe..a3a2396362a5 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -364,8 +364,9 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size)
 /*
  * 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
- * sme_active() and sev_active() functions are used for this.  When a
- * distinction isn't needed, the mem_encrypt_active() function can be used.
+ * PATTR_HOST_MEM_ENCRYPT and PATTR_GUEST_MEM_ENCRYPT flags to
+ * amd_prot_guest_has() are used for this. When a distinction isn't needed,
+ * the mem_encrypt_active() function 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

@@ -377,11 +378,6 @@ bool sev_active(void)
 {
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }
-
-static bool sme_active(void)
-{
-	return sme_me_mask && !sev_active();
-}
 EXPORT_SYMBOL_GPL(sev_active);
 
 /* Needs to be called from non-instrumentable code */

@@ -398,7 +394,7 @@ bool amd_prot_guest_has(unsigned int attr)
 
 	case PATTR_SME:
 	case PATTR_HOST_MEM_ENCRYPT:
-		return sme_active();
+		return sme_me_mask && !sev_active();
 
 	case PATTR_SEV:
 	case PATTR_GUEST_MEM_ENCRYPT:

quoted hunk

 {
 	return sme_me_mask && !sev_active();
 }

@@ -428,7 +428,7 @@ bool force_dma_unencrypted(struct device *dev)
 	 * device does not support DMA to addresses that include the
 	 * encryption mask.
 	 */
-	if (sme_active()) {
+	if (amd_prot_guest_has(PATTR_SME)) {

So I'm not sure: you add PATTR_SME which you call with
amd_prot_guest_has() and PATTR_HOST_MEM_ENCRYPT which you call with
prot_guest_has() and they both end up being the same thing on AMD.

So why even bother with PATTR_SME?

This is only going to cause confusion later and I'd say let's simply use
prot_guest_has(PATTR_HOST_MEM_ENCRYPT) everywhere...

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 06/12] x86/sev: Replace occurrences of sev_active() with prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 10:02:08

On Fri, Aug 13, 2021 at 11:59:25AM -0500, Tom Lendacky wrote:

quoted hunk

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 8e7b517ad738..66ff788b79c9 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c

@@ -167,7 +167,7 @@ static int init_transition_pgtable(struct kimage *image, pgd_t *pgd)
 	}
 	pte = pte_offset_kernel(pmd, vaddr);
 
-	if (sev_active())
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 		prot = PAGE_KERNEL_EXEC;
 
 	set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));

@@ -207,7 +207,7 @@ static int init_pgtable(struct kimage *image, unsigned long start_pgtable)
 	level4p = (pgd_t *)__va(start_pgtable);
 	clear_page(level4p);
 
-	if (sev_active()) {
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT)) {
 		info.page_flag   |= _PAGE_ENC;
 		info.kernpg_flag |= _PAGE_ENC;
 	}

@@ -570,12 +570,12 @@ void arch_kexec_unprotect_crashkres(void)
  */
 int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
 {
-	if (sev_active())
+	if (!prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		return 0;
 
 	/*
-	 * If SME is active we need to be sure that kexec pages are
-	 * not encrypted because when we boot to the new kernel the
+	 * If host memory encryption is active we need to be sure that kexec
+	 * pages are not encrypted because when we boot to the new kernel the
 	 * pages won't be accessed encrypted (initially).
 	 */

That hunk belongs logically into the previous patch which removes
sme_active().

quoted hunk

 	return set_memory_decrypted((unsigned long)vaddr, pages);

@@ -583,12 +583,12 @@ int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
 
 void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages)
 {
-	if (sev_active())
+	if (!prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		return;
 
 	/*
-	 * If SME is active we need to reset the pages back to being
-	 * an encrypted mapping before freeing them.
+	 * If host memory encryption is active we need to reset the pages back
+	 * to being an encrypted mapping before freeing them.
 	 */
 	set_memory_encrypted((unsigned long)vaddr, pages);
 }

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index e8ccab50ebf6..b69f5ac622d5 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c

@@ -25,6 +25,7 @@
 #include <linux/pagemap.h>
 #include <linux/swap.h>
 #include <linux/rwsem.h>
+#include <linux/protected_guest.h>
 
 #include <asm/apic.h>
 #include <asm/perf_event.h>

@@ -457,7 +458,7 @@ static int has_svm(void)
 		return 0;
 	}
 
-	if (sev_active()) {
+	if (prot_guest_has(PATTR_SEV)) {
 		pr_info("KVM is unsupported when running as an SEV guest\n");
 		return 0;

Same question as for PATTR_SME. PATTR_GUEST_MEM_ENCRYPT should be enough.

quoted hunk

@@ -373,7 +373,7 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size)
  * up under SME the trampoline area cannot be encrypted, whereas under SEV
  * the trampoline area must be encrypted.
  */
-bool sev_active(void)
+static bool sev_active(void)
 {
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }
@@ -382,7 +382,6 @@ static bool sme_active(void)
 {
 	return sme_me_mask && !sev_active();
 }
-EXPORT_SYMBOL_GPL(sev_active);

Just get rid of it altogether.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 07/12] x86/sev: Replace occurrences of sev_es_active() with prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 10:07:30

On Fri, Aug 13, 2021 at 11:59:26AM -0500, Tom Lendacky wrote:

Replace occurrences of sev_es_active() with the more generic
prot_guest_has() using PATTR_GUEST_PROT_STATE, except for in
arch/x86/kernel/sev*.c and arch/x86/mm/mem_encrypt*.c where PATTR_SEV_ES
will be used. If future support is added for other memory encyrption
techonologies, the use of PATTR_GUEST_PROT_STATE can be updated, as
required, to specifically use PATTR_SEV_ES.

Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/mem_encrypt.h | 2 --
 arch/x86/kernel/sev.c              | 6 +++---
 arch/x86/mm/mem_encrypt.c          | 7 +++----
 arch/x86/realmode/init.c           | 3 +--
 4 files changed, 7 insertions(+), 11 deletions(-)

Same comments to this one as for the previous two.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 09/12] mm: Remove the now unused mem_encrypt_active() function

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 10:22:04

On Fri, Aug 13, 2021 at 11:59:28AM -0500, Tom Lendacky wrote:

quoted hunk

The mem_encrypt_active() function has been replaced by prot_guest_has(),
so remove the implementation.

Reviewed-by: Joerg Roedel <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 include/linux/mem_encrypt.h | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/include/linux/mem_encrypt.h b/include/linux/mem_encrypt.h
index 5c4a18a91f89..ae4526389261 100644
--- a/include/linux/mem_encrypt.h
+++ b/include/linux/mem_encrypt.h

@@ -16,10 +16,6 @@
 
 #include <asm/mem_encrypt.h>
 
-#else	/* !CONFIG_ARCH_HAS_MEM_ENCRYPT */
-
-static inline bool mem_encrypt_active(void) { return false; }
-
 #endif	/* CONFIG_ARCH_HAS_MEM_ENCRYPT */
 
 #ifdef CONFIG_AMD_MEM_ENCRYPT

--

This one wants to be part of the previous patch.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 09/12] mm: Remove the now unused mem_encrypt_active() function

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 10:23:48

On Tue, Aug 17, 2021 at 12:22:33PM +0200, Borislav Petkov wrote:

This one wants to be part of the previous patch.

... and the three following patches too - the treewide patch does a
single atomic :) replacement and that's it.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 04/12] powerpc/pseries/svm: Add a powerpc version of prot_guest_has()

From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2021-08-17 12:38:32

Tom Lendacky [off-list ref] writes:

quoted hunk

Introduce a powerpc version of the prot_guest_has() function. This will
be used to replace the powerpc mem_encrypt_active() implementation, so
the implementation will initially only support the PATTR_MEM_ENCRYPT
attribute.

Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/powerpc/include/asm/protected_guest.h | 30 ++++++++++++++++++++++
 arch/powerpc/platforms/pseries/Kconfig     |  1 +
 2 files changed, 31 insertions(+)
 create mode 100644 arch/powerpc/include/asm/protected_guest.h

diff --git a/arch/powerpc/include/asm/protected_guest.h b/arch/powerpc/include/asm/protected_guest.h
new file mode 100644
index 000000000000..ce55c2c7e534
--- /dev/null
+++ b/arch/powerpc/include/asm/protected_guest.h

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _POWERPC_PROTECTED_GUEST_H
+#define _POWERPC_PROTECTED_GUEST_H

Minor nit, we would usually use _ASM_POWERPC_PROTECTED_GUEST_H

Otherwise looks OK to me.

Acked-by: Michael Ellerman <mpe@ellerman.id.au>

cheers

Re: [PATCH v2 04/12] powerpc/pseries/svm: Add a powerpc version of prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-17 14:12:06

On 8/17/21 3:35 AM, Borislav Petkov wrote:

On Fri, Aug 13, 2021 at 11:59:23AM -0500, Tom Lendacky wrote:

quoted

Introduce a powerpc version of the prot_guest_has() function. This will
be used to replace the powerpc mem_encrypt_active() implementation, so
the implementation will initially only support the PATTR_MEM_ENCRYPT
attribute.

Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/powerpc/include/asm/protected_guest.h | 30 ++++++++++++++++++++++
 arch/powerpc/platforms/pseries/Kconfig     |  1 +
 2 files changed, 31 insertions(+)
 create mode 100644 arch/powerpc/include/asm/protected_guest.h

diff --git a/arch/powerpc/include/asm/protected_guest.h b/arch/powerpc/include/asm/protected_guest.h
new file mode 100644
index 000000000000..ce55c2c7e534
--- /dev/null
+++ b/arch/powerpc/include/asm/protected_guest.h

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Protected Guest (and Host) Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _POWERPC_PROTECTED_GUEST_H
+#define _POWERPC_PROTECTED_GUEST_H
+
+#include <asm/svm.h>
+
+#ifndef __ASSEMBLY__

Same thing here. Pls audit the whole set whether those __ASSEMBLY__
guards are really needed and remove them if not.

Will do.

Thanks,
Tom

Thx.

Re: [PATCH v2 05/12] x86/sme: Replace occurrences of sme_active() with prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-17 14:47:07

On 8/17/21 4:00 AM, Borislav Petkov wrote:

On Fri, Aug 13, 2021 at 11:59:24AM -0500, Tom Lendacky wrote:

quoted

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index edc67ddf065d..5635ca9a1fbe 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -144,7 +144,7 @@ void __init sme_unmap_bootdata(char *real_mode_data)
 	struct boot_params *boot_data;
 	unsigned long cmdline_paddr;
 
-	if (!sme_active())
+	if (!amd_prot_guest_has(PATTR_SME))
 		return;
 
 	/* Get the command line address before unmapping the real_mode_data */

@@ -164,7 +164,7 @@ void __init sme_map_bootdata(char *real_mode_data)
 	struct boot_params *boot_data;
 	unsigned long cmdline_paddr;
 
-	if (!sme_active())
+	if (!amd_prot_guest_has(PATTR_SME))
 		return;
 
 	__sme_early_map_unmap_mem(real_mode_data, sizeof(boot_params), true);

@@ -378,7 +378,7 @@ bool sev_active(void)
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }
 
-bool sme_active(void)
+static bool sme_active(void)

Just get rid of it altogether. Also, there's an

EXPORT_SYMBOL_GPL(sev_active);

quoted

which needs to go under the actual function. Here's a diff ontop:

Will do.

quoted hunk

---

diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 5635ca9a1fbe..a3a2396362a5 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -364,8 +364,9 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size)
 /*
  * 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
- * sme_active() and sev_active() functions are used for this.  When a
- * distinction isn't needed, the mem_encrypt_active() function can be used.
+ * PATTR_HOST_MEM_ENCRYPT and PATTR_GUEST_MEM_ENCRYPT flags to
+ * amd_prot_guest_has() are used for this. When a distinction isn't needed,
+ * the mem_encrypt_active() function 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

@@ -377,11 +378,6 @@ bool sev_active(void)
 {
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }
-
-static bool sme_active(void)
-{
-	return sme_me_mask && !sev_active();
-}
 EXPORT_SYMBOL_GPL(sev_active);
 
 /* Needs to be called from non-instrumentable code */

@@ -398,7 +394,7 @@ bool amd_prot_guest_has(unsigned int attr)
 
 	case PATTR_SME:
 	case PATTR_HOST_MEM_ENCRYPT:
-		return sme_active();
+		return sme_me_mask && !sev_active();
 
 	case PATTR_SEV:
 	case PATTR_GUEST_MEM_ENCRYPT:

quoted

 {
 	return sme_me_mask && !sev_active();
 }

@@ -428,7 +428,7 @@ bool force_dma_unencrypted(struct device *dev)
 	 * device does not support DMA to addresses that include the
 	 * encryption mask.
 	 */
-	if (sme_active()) {
+	if (amd_prot_guest_has(PATTR_SME)) {

So I'm not sure: you add PATTR_SME which you call with
amd_prot_guest_has() and PATTR_HOST_MEM_ENCRYPT which you call with
prot_guest_has() and they both end up being the same thing on AMD.

So why even bother with PATTR_SME?

This is only going to cause confusion later and I'd say let's simply use
prot_guest_has(PATTR_HOST_MEM_ENCRYPT) everywhere...

Ok, I can do that. I was trying to ensure that anything that is truly SME
or SEV specific would be called out now.

I'm ok with letting the TDX folks make changes to these calls to be SME or
SEV specific, if necessary, later.

Thanks,
Tom

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-17 15:23:01

On 8/15/21 9:39 AM, Borislav Petkov wrote:

On Sun, Aug 15, 2021 at 08:53:31AM -0500, Tom Lendacky wrote:

quoted

It's not a cross-vendor thing as opposed to a KVM or other hypervisor
thing where the family doesn't have to be reported as AMD or HYGON.

What would be the use case? A HV starts a guest which is supposed to be
encrypted using the AMD's confidential guest technology but the HV tells
the guest that it is not running on an AMD SVM HV but something else?

Is that even an actual use case?

Or am I way off?

I know we have talked about this in the past but this still sounds
insane.

Maybe the KVM folks have a better understanding of it...

I can change it to be an AMD/HYGON check...  although, I'll have to check
to see if any (very) early use of the function will work with that.

At a minimum, the check in arch/x86/kernel/head64.c will have to be
changed or removed. I'll take a closer look.

Thanks,
Tom

Re: [PATCH v2 06/12] x86/sev: Replace occurrences of sev_active() with prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-17 15:26:27

On 8/17/21 5:02 AM, Borislav Petkov wrote:

On Fri, Aug 13, 2021 at 11:59:25AM -0500, Tom Lendacky wrote:

quoted

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 8e7b517ad738..66ff788b79c9 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c

@@ -167,7 +167,7 @@ static int init_transition_pgtable(struct kimage *image, pgd_t *pgd)
 	}
 	pte = pte_offset_kernel(pmd, vaddr);
 
-	if (sev_active())
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT))
 		prot = PAGE_KERNEL_EXEC;
 
 	set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));

@@ -207,7 +207,7 @@ static int init_pgtable(struct kimage *image, unsigned long start_pgtable)
 	level4p = (pgd_t *)__va(start_pgtable);
 	clear_page(level4p);
 
-	if (sev_active()) {
+	if (prot_guest_has(PATTR_GUEST_MEM_ENCRYPT)) {
 		info.page_flag   |= _PAGE_ENC;
 		info.kernpg_flag |= _PAGE_ENC;
 	}

@@ -570,12 +570,12 @@ void arch_kexec_unprotect_crashkres(void)
  */
 int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
 {
-	if (sev_active())
+	if (!prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		return 0;
 
 	/*
-	 * If SME is active we need to be sure that kexec pages are
-	 * not encrypted because when we boot to the new kernel the
+	 * If host memory encryption is active we need to be sure that kexec
+	 * pages are not encrypted because when we boot to the new kernel the
 	 * pages won't be accessed encrypted (initially).
 	 */

That hunk belongs logically into the previous patch which removes
sme_active().

I was trying to keep the sev_active() changes separate... so even though
it's an SME thing, I kept it here. But I can move it to the previous
patch, it just might look strange.

quoted

 	return set_memory_decrypted((unsigned long)vaddr, pages);

@@ -583,12 +583,12 @@ int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
 
 void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages)
 {
-	if (sev_active())
+	if (!prot_guest_has(PATTR_HOST_MEM_ENCRYPT))
 		return;
 
 	/*
-	 * If SME is active we need to reset the pages back to being
-	 * an encrypted mapping before freeing them.
+	 * If host memory encryption is active we need to reset the pages back
+	 * to being an encrypted mapping before freeing them.
 	 */
 	set_memory_encrypted((unsigned long)vaddr, pages);
 }

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index e8ccab50ebf6..b69f5ac622d5 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c

@@ -25,6 +25,7 @@
 #include <linux/pagemap.h>
 #include <linux/swap.h>
 #include <linux/rwsem.h>
+#include <linux/protected_guest.h>
 
 #include <asm/apic.h>
 #include <asm/perf_event.h>

@@ -457,7 +458,7 @@ static int has_svm(void)
 		return 0;
 	}
 
-	if (sev_active()) {
+	if (prot_guest_has(PATTR_SEV)) {
 		pr_info("KVM is unsupported when running as an SEV guest\n");
 		return 0;

Same question as for PATTR_SME. PATTR_GUEST_MEM_ENCRYPT should be enough.

Yup, I'll change them all.

quoted

@@ -373,7 +373,7 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size)
  * up under SME the trampoline area cannot be encrypted, whereas under SEV
  * the trampoline area must be encrypted.
  */
-bool sev_active(void)
+static bool sev_active(void)
 {
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }
@@ -382,7 +382,6 @@ static bool sme_active(void)
 {
 	return sme_me_mask && !sev_active();
 }
-EXPORT_SYMBOL_GPL(sev_active);

Just get rid of it altogether.

Ok.

Thanks,
Tom

Thx.

Re: [PATCH v2 09/12] mm: Remove the now unused mem_encrypt_active() function

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-17 15:30:16

On 8/17/21 5:24 AM, Borislav Petkov wrote:

On Tue, Aug 17, 2021 at 12:22:33PM +0200, Borislav Petkov wrote:

quoted

This one wants to be part of the previous patch.

... and the three following patches too - the treewide patch does a
single atomic :) replacement and that's it.

Ok, I'll squash those all together.

Thanks,
Tom

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 18:39:07

On Tue, Aug 17, 2021 at 10:22:52AM -0500, Tom Lendacky wrote:

I can change it to be an AMD/HYGON check...  although, I'll have to check
to see if any (very) early use of the function will work with that.

We can always change it later if really needed. It is just that I'm not
a fan of such "preemptive" changes.

At a minimum, the check in arch/x86/kernel/head64.c will have to be
changed or removed. I'll take a closer look.

Yeah, sme_me_mask, already discussed on IRC.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 05/12] x86/sme: Replace occurrences of sme_active() with prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 18:40:43

On Tue, Aug 17, 2021 at 09:46:58AM -0500, Tom Lendacky wrote:

I'm ok with letting the TDX folks make changes to these calls to be SME or
SEV specific, if necessary, later.

Yap, exactly. Let's add the specific stuff only when really needed.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 06/12] x86/sev: Replace occurrences of sev_active() with prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 18:42:27

On Tue, Aug 17, 2021 at 10:26:18AM -0500, Tom Lendacky wrote:

quoted

 	/*
-	 * If SME is active we need to be sure that kexec pages are
-	 * not encrypted because when we boot to the new kernel the
+	 * If host memory encryption is active we need to be sure that kexec
+	 * pages are not encrypted because when we boot to the new kernel the
 	 * pages won't be accessed encrypted (initially).
 	 */

That hunk belongs logically into the previous patch which removes
sme_active().

I was trying to keep the sev_active() changes separate... so even though
it's an SME thing, I kept it here. But I can move it to the previous
patch, it just might look strange.

Oh I meant only the comment because it is a SME-related change. But not
too important so whatever.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 02/12] mm: Introduce a function to check for virtualization protection features

From: Christoph Hellwig <hch@infradead.org>
Date: 2021-08-19 09:47:48

On Fri, Aug 13, 2021 at 11:59:21AM -0500, Tom Lendacky wrote:

+#define PATTR_MEM_ENCRYPT		0	/* Encrypted memory */
+#define PATTR_HOST_MEM_ENCRYPT		1	/* Host encrypted memory */
+#define PATTR_GUEST_MEM_ENCRYPT		2	/* Guest encrypted memory */
+#define PATTR_GUEST_PROT_STATE		3	/* Guest encrypted state */

Please write an actual detailed explanaton of what these mean, that
is what implications it has on the kernel.

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Christoph Hellwig <hch@infradead.org>
Date: 2021-08-19 09:54:21

On Fri, Aug 13, 2021 at 11:59:22AM -0500, Tom Lendacky wrote:

While the name suggests this is intended mainly for guests, it will
also be used for host memory encryption checks in place of sme_active().

Which suggest that the name is not good to start with.  Maybe protected
hardware, system or platform might be a better choice?

+static inline bool prot_guest_has(unsigned int attr)
+{
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+	if (sme_me_mask)
+		return amd_prot_guest_has(attr);
+#endif
+
+	return false;
+}

Shouldn't this be entirely out of line?

+/* 0x800 - 0x8ff reserved for AMD */
+#define PATTR_SME			0x800
+#define PATTR_SEV			0x801
+#define PATTR_SEV_ES			0x802

Why do we need reservations for a purely in-kernel namespace?

And why are you overoading a brand new generic API with weird details
of a specific implementation like this?

Re: [PATCH v2 04/12] powerpc/pseries/svm: Add a powerpc version of prot_guest_has()

From: Christoph Hellwig <hch@infradead.org>
Date: 2021-08-19 09:56:20

On Fri, Aug 13, 2021 at 11:59:23AM -0500, Tom Lendacky wrote:

+static inline bool prot_guest_has(unsigned int attr)

No reall need to have this inline.  In fact I'd suggest we havea the
prototype in a common header so that everyone must implement it out
of line.

Re: [PATCH v2 02/12] mm: Introduce a function to check for virtualization protection features

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-19 16:40:11

On 8/19/21 4:46 AM, Christoph Hellwig wrote:

On Fri, Aug 13, 2021 at 11:59:21AM -0500, Tom Lendacky wrote:

quoted

+#define PATTR_MEM_ENCRYPT		0	/* Encrypted memory */
+#define PATTR_HOST_MEM_ENCRYPT		1	/* Host encrypted memory */
+#define PATTR_GUEST_MEM_ENCRYPT		2	/* Guest encrypted memory */
+#define PATTR_GUEST_PROT_STATE		3	/* Guest encrypted state */

Please write an actual detailed explanaton of what these mean, that
is what implications it has on the kernel.

Will do.

Thanks,
Tom

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-19 17:26:00

On Thu, Aug 19, 2021 at 10:52:53AM +0100, Christoph Hellwig wrote:

Which suggest that the name is not good to start with.  Maybe protected
hardware, system or platform might be a better choice?

Yah, coming up with a proper name here hasn't been easy.
prot_guest_has() is not the first variant.

From all three things you suggest above, I guess calling it a "platform"
is the closest. As in, this is a confidential computing platform which
provides host and guest facilities etc.

So calling it

confidential_computing_platform_has()

is obviously too long.

ccp_has() clashes with the namespace of drivers/crypto/ccp/ which is
used by the technology too.

coco_platform_has() is too unserious.

So I guess

cc_platform_has()

ain't all that bad.

Unless you have a better idea, ofc.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-19 18:33:17

On 8/19/21 4:52 AM, Christoph Hellwig wrote:

On Fri, Aug 13, 2021 at 11:59:22AM -0500, Tom Lendacky wrote:

quoted

While the name suggests this is intended mainly for guests, it will
also be used for host memory encryption checks in place of sme_active().

Which suggest that the name is not good to start with.  Maybe protected
hardware, system or platform might be a better choice?

quoted

+static inline bool prot_guest_has(unsigned int attr)
+{
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+	if (sme_me_mask)
+		return amd_prot_guest_has(attr);
+#endif
+
+	return false;
+}

Shouldn't this be entirely out of line?

I did it as inline originally because the presence of the function will be
decided based on the ARCH_HAS_PROTECTED_GUEST config. For now, that is
only selected by the AMD memory encryption support, so if I went out of
line I could put in mem_encrypt.c. But with TDX wanting to also use it, it
would have to be in an always built file with some #ifdefs or in its own
file that is conditionally built based on the ARCH_HAS_PROTECTED_GUEST
setting (they've already tried building with ARCH_HAS_PROTECTED_GUEST=y
and AMD_MEM_ENCRYPT not set).

To take it out of line, I'm leaning towards the latter, creating a new
file that is built based on the ARCH_HAS_PROTECTED_GUEST setting.

quoted

+/* 0x800 - 0x8ff reserved for AMD */
+#define PATTR_SME			0x800
+#define PATTR_SEV			0x801
+#define PATTR_SEV_ES			0x802

Why do we need reservations for a purely in-kernel namespace?

And why are you overoading a brand new generic API with weird details
of a specific implementation like this?

There was some talk about this on the mailing list where TDX and SEV may
need to be differentiated, so we wanted to reserve a range of values per
technology. I guess I can remove them until they are actually needed.

Thanks,
Tom

Re: [PATCH v2 04/12] powerpc/pseries/svm: Add a powerpc version of prot_guest_has()

From: Tom Lendacky <thomas.lendacky@amd.com>
Date: 2021-08-19 18:34:52

On 8/19/21 4:55 AM, Christoph Hellwig wrote:

On Fri, Aug 13, 2021 at 11:59:23AM -0500, Tom Lendacky wrote:

quoted

+static inline bool prot_guest_has(unsigned int attr)

No reall need to have this inline.  In fact I'd suggest we havea the
prototype in a common header so that everyone must implement it out
of line.

I'll do the same thing I end up doing for x86.

Thanks,
Tom

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: "Kuppuswamy, Sathyanarayanan" <sathyanarayanan.kuppuswamy@linux.intel.com>
Date: 2021-08-19 19:57:54


On 8/19/21 11:33 AM, Tom Lendacky wrote:

There was some talk about this on the mailing list where TDX and SEV may
need to be differentiated, so we wanted to reserve a range of values per
technology. I guess I can remove them until they are actually needed.

In TDX also we have similar requirements and we need some flags for
TDX specific checks. So I think it is fine to leave some space for vendor
flags.

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer

Re: [PATCH v2 03/12] x86/sev: Add an x86 version of prot_guest_has()

From: Christoph Hellwig <hch@infradead.org>
Date: 2021-08-24 07:16:24

On Thu, Aug 19, 2021 at 01:33:09PM -0500, Tom Lendacky wrote:

I did it as inline originally because the presence of the function will be
decided based on the ARCH_HAS_PROTECTED_GUEST config. For now, that is
only selected by the AMD memory encryption support, so if I went out of
line I could put in mem_encrypt.c. But with TDX wanting to also use it, it
would have to be in an always built file with some #ifdefs or in its own
file that is conditionally built based on the ARCH_HAS_PROTECTED_GUEST
setting (they've already tried building with ARCH_HAS_PROTECTED_GUEST=y
and AMD_MEM_ENCRYPT not set).

To take it out of line, I'm leaning towards the latter, creating a new
file that is built based on the ARCH_HAS_PROTECTED_GUEST setting.

Yes.  In general everytime architectures have to provide the prototype
and not just the implementation of something we end up with a giant mess
sooner or later.  In a few cases that is still warranted due to
performance concerns, but i don't think that is the case here.

quoted

+/* 0x800 - 0x8ff reserved for AMD */
+#define PATTR_SME			0x800
+#define PATTR_SEV			0x801
+#define PATTR_SEV_ES			0x802

Why do we need reservations for a purely in-kernel namespace?

And why are you overoading a brand new generic API with weird details
of a specific implementation like this?

There was some talk about this on the mailing list where TDX and SEV may
need to be differentiated, so we wanted to reserve a range of values per
technology. I guess I can remove them until they are actually needed.

In that case add a flag for the differing behavior.  And only add them
when actually needed.  And either way there is absolutely no need to
reserve ranges.

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