[PATCH v4 0/8] Implement generic cc_platform_has() helper function

[PATCH v4 0/8] Implement generic cc_platform_has() helper function

[Borislav Petkov]

From: Borislav Petkov <bp@suse.de>

Hi all,

here's v4 of the cc_platform_has() patchset with feedback incorporated.

I'm going to route this through tip if there are no objections.

Thx.

Tom Lendacky (8):
  x86/ioremap: Selectively build arch override encryption functions
  arch/cc: Introduce a function to check for confidential computing
    features
  x86/sev: Add an x86 version of cc_platform_has()
  powerpc/pseries/svm: Add a powerpc version of cc_platform_has()
  x86/sme: Replace occurrences of sme_active() with cc_platform_has()
  x86/sev: Replace occurrences of sev_active() with cc_platform_has()
  x86/sev: Replace occurrences of sev_es_active() with cc_platform_has()
  treewide: Replace the use of mem_encrypt_active() with
    cc_platform_has()

 arch/Kconfig                                 |  3 +
 arch/powerpc/include/asm/mem_encrypt.h       |  5 --
 arch/powerpc/platforms/pseries/Kconfig       |  1 +
 arch/powerpc/platforms/pseries/Makefile      |  2 +
 arch/powerpc/platforms/pseries/cc_platform.c | 26 ++++++
 arch/powerpc/platforms/pseries/svm.c         |  5 +-
 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           | 12 +--
 arch/x86/kernel/Makefile                     |  6 ++
 arch/x86/kernel/cc_platform.c                | 69 +++++++++++++++
 arch/x86/kernel/crash_dump_64.c              |  4 +-
 arch/x86/kernel/head64.c                     |  9 +-
 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                    | 55 ++++--------
 arch/x86/mm/mem_encrypt_identity.c           |  9 +-
 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/cc_platform.h                  | 88 ++++++++++++++++++++
 include/linux/mem_encrypt.h                  |  4 -
 kernel/dma/swiotlb.c                         |  4 +-
 40 files changed, 310 insertions(+), 129 deletions(-)
 create mode 100644 arch/powerpc/platforms/pseries/cc_platform.c
 create mode 100644 arch/x86/kernel/cc_platform.c
 create mode 100644 include/linux/cc_platform.h

-- 
2.29.2

[PATCH 1/8] x86/ioremap: Selectively build arch override encryption functions

[Borislav Petkov]

From: Tom Lendacky <thomas.lendacky@amd.com>

In preparation for other uses of the cc_platform_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.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
---
 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)
-- 
2.29.2

[PATCH 2/8] arch/cc: Introduce a function to check for confidential computing features

[Borislav Petkov]

From: Tom Lendacky <thomas.lendacky@amd.com>

In preparation for other confidential computing technologies, introduce
a generic helper function, cc_platform_has(), that can be used to
check for specific active confidential computing 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() || ... ).

 [ bp: s/_CC_PLATFORM_H/_LINUX_CC_PLATFORM_H/g ]

Co-developed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
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>
Signed-off-by: Borislav Petkov <bp@suse.de>
---
 arch/Kconfig                |  3 ++
 include/linux/cc_platform.h | 88 +++++++++++++++++++++++++++++++++++++
 2 files changed, 91 insertions(+)
 create mode 100644 include/linux/cc_platform.h

diff --git a/arch/Kconfig b/arch/Kconfig
index 8df1c7102643..d1e69d6e8498 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1234,6 +1234,9 @@ config RELR
 config ARCH_HAS_MEM_ENCRYPT
 	bool
 
+config ARCH_HAS_CC_PLATFORM
+	bool
+
 config HAVE_SPARSE_SYSCALL_NR
        bool
        help
diff --git a/include/linux/cc_platform.h b/include/linux/cc_platform.h
new file mode 100644
index 000000000000..a075b70b9a70
--- /dev/null
+++ b/include/linux/cc_platform.h
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Confidential Computing Platform Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#ifndef _LINUX_CC_PLATFORM_H
+#define _LINUX_CC_PLATFORM_H
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+
+/**
+ * enum cc_attr - Confidential computing attributes
+ *
+ * These attributes represent confidential computing features that are
+ * currently active.
+ */
+enum cc_attr {
+	/**
+	 * @CC_ATTR_MEM_ENCRYPT: Memory encryption is active
+	 *
+	 * The platform/OS is running with active memory encryption. This
+	 * includes running either as a bare-metal system or a hypervisor
+	 * and actively using memory encryption or as a guest/virtual machine
+	 * and actively using memory encryption.
+	 *
+	 * Examples include SME, SEV and SEV-ES.
+	 */
+	CC_ATTR_MEM_ENCRYPT,
+
+	/**
+	 * @CC_ATTR_HOST_MEM_ENCRYPT: Host memory encryption is active
+	 *
+	 * The platform/OS is running as a bare-metal system or a hypervisor
+	 * and actively using memory encryption.
+	 *
+	 * Examples include SME.
+	 */
+	CC_ATTR_HOST_MEM_ENCRYPT,
+
+	/**
+	 * @CC_ATTR_GUEST_MEM_ENCRYPT: Guest memory encryption is active
+	 *
+	 * The platform/OS is running as a guest/virtual machine and actively
+	 * using memory encryption.
+	 *
+	 * Examples include SEV and SEV-ES.
+	 */
+	CC_ATTR_GUEST_MEM_ENCRYPT,
+
+	/**
+	 * @CC_ATTR_GUEST_STATE_ENCRYPT: Guest state encryption is active
+	 *
+	 * The platform/OS is running as a guest/virtual machine and actively
+	 * using memory encryption and register state encryption.
+	 *
+	 * Examples include SEV-ES.
+	 */
+	CC_ATTR_GUEST_STATE_ENCRYPT,
+};
+
+#ifdef CONFIG_ARCH_HAS_CC_PLATFORM
+
+/**
+ * cc_platform_has() - Checks if the specified cc_attr attribute is active
+ * @attr: Confidential computing attribute to check
+ *
+ * The cc_platform_has() function will return an indicator as to whether the
+ * specified Confidential Computing attribute is currently active.
+ *
+ * Context: Any context
+ * Return:
+ * * TRUE  - Specified Confidential Computing attribute is active
+ * * FALSE - Specified Confidential Computing attribute is not active
+ */
+bool cc_platform_has(enum cc_attr attr);
+
+#else	/* !CONFIG_ARCH_HAS_CC_PLATFORM */
+
+static inline bool cc_platform_has(enum cc_attr attr) { return false; }
+
+#endif	/* CONFIG_ARCH_HAS_CC_PLATFORM */
+
+#endif	/* _LINUX_CC_PLATFORM_H */
-- 
2.29.2

[PATCH 3/8] x86/sev: Add an x86 version of cc_platform_has()

[Borislav Petkov]

From: Tom Lendacky <thomas.lendacky@amd.com>

Introduce an x86 version of the cc_platform_has() function. This will be
used to replace vendor specific calls like sme_active(), sev_active(),
etc.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
---
 arch/x86/Kconfig                   |  1 +
 arch/x86/include/asm/mem_encrypt.h |  1 +
 arch/x86/kernel/Makefile           |  6 +++
 arch/x86/kernel/cc_platform.c      | 69 ++++++++++++++++++++++++++++++
 arch/x86/mm/mem_encrypt.c          |  1 +
 5 files changed, 78 insertions(+)
 create mode 100644 arch/x86/kernel/cc_platform.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index ab83c22d274e..9f190ec4f953 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1518,6 +1518,7 @@ config AMD_MEM_ENCRYPT
 	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
 	select INSTRUCTION_DECODER
 	select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
+	select ARCH_HAS_CC_PLATFORM
 	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..3fb9f5ebefa4 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h
@@ -13,6 +13,7 @@
 #ifndef __ASSEMBLY__
 
 #include <linux/init.h>
+#include <linux/cc_platform.h>
 
 #include <asm/bootparam.h>
 
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 8f4e8fa6ed75..2ff3e600f426 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -21,6 +21,7 @@ CFLAGS_REMOVE_ftrace.o = -pg
 CFLAGS_REMOVE_early_printk.o = -pg
 CFLAGS_REMOVE_head64.o = -pg
 CFLAGS_REMOVE_sev.o = -pg
+CFLAGS_REMOVE_cc_platform.o = -pg
 endif
 
 KASAN_SANITIZE_head$(BITS).o				:= n
@@ -29,6 +30,7 @@ KASAN_SANITIZE_dumpstack_$(BITS).o			:= n
 KASAN_SANITIZE_stacktrace.o				:= n
 KASAN_SANITIZE_paravirt.o				:= n
 KASAN_SANITIZE_sev.o					:= n
+KASAN_SANITIZE_cc_platform.o				:= n
 
 # With some compiler versions the generated code results in boot hangs, caused
 # by several compilation units. To be safe, disable all instrumentation.
@@ -47,6 +49,7 @@ endif
 KCOV_INSTRUMENT		:= n
 
 CFLAGS_head$(BITS).o	+= -fno-stack-protector
+CFLAGS_cc_platform.o	+= -fno-stack-protector
 
 CFLAGS_irq.o := -I $(srctree)/$(src)/../include/asm/trace
 
@@ -147,6 +150,9 @@ obj-$(CONFIG_UNWINDER_FRAME_POINTER)	+= unwind_frame.o
 obj-$(CONFIG_UNWINDER_GUESS)		+= unwind_guess.o
 
 obj-$(CONFIG_AMD_MEM_ENCRYPT)		+= sev.o
+
+obj-$(CONFIG_ARCH_HAS_CC_PLATFORM)	+= cc_platform.o
+
 ###
 # 64 bit specific files
 ifeq ($(CONFIG_X86_64),y)
diff --git a/arch/x86/kernel/cc_platform.c b/arch/x86/kernel/cc_platform.c
new file mode 100644
index 000000000000..03bb2f343ddb
--- /dev/null
+++ b/arch/x86/kernel/cc_platform.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Confidential Computing Platform Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#include <linux/export.h>
+#include <linux/cc_platform.h>
+#include <linux/mem_encrypt.h>
+
+#include <asm/processor.h>
+
+static bool __maybe_unused intel_cc_platform_has(enum cc_attr attr)
+{
+#ifdef CONFIG_INTEL_TDX_GUEST
+	return false;
+#else
+	return false;
+#endif
+}
+
+/*
+ * SME and SEV are very similar but they are not the same, so there are
+ * times that the kernel will need to distinguish between SME and SEV. The
+ * cc_platform_has() function is used for this.  When a distinction isn't
+ * needed, the CC_ATTR_MEM_ENCRYPT attribute can be used.
+ *
+ * The trampoline code is a good example for this requirement.  Before
+ * paging is activated, SME will access all memory as decrypted, but SEV
+ * will access all memory as encrypted.  So, when APs are being brought
+ * up under SME the trampoline area cannot be encrypted, whereas under SEV
+ * the trampoline area must be encrypted.
+ */
+static bool amd_cc_platform_has(enum cc_attr attr)
+{
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+	switch (attr) {
+	case CC_ATTR_MEM_ENCRYPT:
+		return sme_me_mask;
+
+	case CC_ATTR_HOST_MEM_ENCRYPT:
+		return sme_me_mask && !(sev_status & MSR_AMD64_SEV_ENABLED);
+
+	case CC_ATTR_GUEST_MEM_ENCRYPT:
+		return sev_status & MSR_AMD64_SEV_ENABLED;
+
+	case CC_ATTR_GUEST_STATE_ENCRYPT:
+		return sev_status & MSR_AMD64_SEV_ES_ENABLED;
+
+	default:
+		return false;
+	}
+#else
+	return false;
+#endif
+}
+
+
+bool cc_platform_has(enum cc_attr attr)
+{
+	if (sme_me_mask)
+		return amd_cc_platform_has(attr);
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(cc_platform_has);
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index ff08dc463634..e29b1418d00c 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/cc_platform.h>
 
 #include <asm/tlbflush.h>
 #include <asm/fixmap.h>
-- 
2.29.2

[PATCH 4/8] powerpc/pseries/svm: Add a powerpc version of cc_platform_has()

[Borislav Petkov]

From: Tom Lendacky <thomas.lendacky@amd.com>

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

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/Kconfig       |  1 +
 arch/powerpc/platforms/pseries/Makefile      |  2 ++
 arch/powerpc/platforms/pseries/cc_platform.c | 26 ++++++++++++++++++++
 3 files changed, 29 insertions(+)
 create mode 100644 arch/powerpc/platforms/pseries/cc_platform.c

diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index 5e037df2a3a1..2e57391e0778 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_CC_PLATFORM
 	help
 	 There are certain POWER platforms which support secure guests using
 	 the Protected Execution Facility, with the help of an Ultravisor
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index 4cda0ef87be0..41d8aee98da4 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -31,3 +31,5 @@ obj-$(CONFIG_FA_DUMP)		+= rtas-fadump.o
 
 obj-$(CONFIG_SUSPEND)		+= suspend.o
 obj-$(CONFIG_PPC_VAS)		+= vas.o
+
+obj-$(CONFIG_ARCH_HAS_CC_PLATFORM)	+= cc_platform.o
diff --git a/arch/powerpc/platforms/pseries/cc_platform.c b/arch/powerpc/platforms/pseries/cc_platform.c
new file mode 100644
index 000000000000..e8021af83a19
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/cc_platform.c
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Confidential Computing Platform Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#include <linux/export.h>
+#include <linux/cc_platform.h>
+
+#include <asm/machdep.h>
+#include <asm/svm.h>
+
+bool cc_platform_has(enum cc_attr attr)
+{
+	switch (attr) {
+	case CC_ATTR_MEM_ENCRYPT:
+		return is_secure_guest();
+
+	default:
+		return false;
+	}
+}
+EXPORT_SYMBOL_GPL(cc_platform_has);
-- 
2.29.2

[PATCH 5/8] x86/sme: Replace occurrences of sme_active() with cc_platform_has()

[Borislav Petkov]

From: Tom Lendacky <thomas.lendacky@amd.com>

Replace uses of sme_active() with the more generic cc_platform_has()
using CC_ATTR_HOST_MEM_ENCRYPT. If future support is added for other
memory encryption technologies, the use of CC_ATTR_HOST_MEM_ENCRYPT
can be updated, as required.

This also replaces two usages of sev_active() that are really geared
towards detecting if SME is active.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
---
 arch/x86/include/asm/kexec.h         |  2 +-
 arch/x86/include/asm/mem_encrypt.h   |  2 --
 arch/x86/kernel/machine_kexec_64.c   | 15 ++++++++-------
 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            | 13 ++++---------
 arch/x86/mm/mem_encrypt_identity.c   |  9 ++++++++-
 arch/x86/realmode/init.c             |  5 +++--
 drivers/iommu/amd/init.c             |  7 ++++---
 10 files changed, 36 insertions(+), 34 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 3fb9f5ebefa4..63c5b99ccae5 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h
@@ -51,7 +51,6 @@ 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);
 
@@ -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; }
 
diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 131f30fdcfbd..7040c0fa921c 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/cc_platform.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());
+				       cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT));
 
 #ifdef CONFIG_KEXEC_JUMP
 	if (image->preserve_context)
@@ -569,12 +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 (!cc_platform_has(CC_ATTR_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);
@@ -582,12 +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 (!cc_platform_has(CC_ATTR_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/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
index c2cfa5e7c152..814ab46a0dad 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/cc_platform.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 (cc_platform_has(CC_ATTR_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..a7250fa3d45f 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/cc_platform.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 (cc_platform_has(CC_ATTR_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 (cc_platform_has(CC_ATTR_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 e29b1418d00c..2163485a74e1 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 (!cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT))
 		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 (!cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT))
 		return;
 
 	__sme_early_map_unmap_mem(real_mode_data, sizeof(boot_params), true);
@@ -377,11 +377,6 @@ bool sev_active(void)
 {
 	return sev_status & MSR_AMD64_SEV_ENABLED;
 }
-
-bool sme_active(void)
-{
-	return sme_me_mask && !sev_active();
-}
 EXPORT_SYMBOL_GPL(sev_active);
 
 /* Needs to be called from non-instrumentable code */
@@ -404,7 +399,7 @@ bool force_dma_unencrypted(struct device *dev)
 	 * device does not support DMA to addresses that include the
 	 * encryption mask.
 	 */
-	if (sme_active()) {
+	if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) {
 		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);
@@ -445,7 +440,7 @@ static void print_mem_encrypt_feature_info(void)
 	pr_info("AMD Memory Encryption Features active:");
 
 	/* Secure Memory Encryption */
-	if (sme_active()) {
+	if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) {
 		/*
 		 * 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..f8c612902038 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/cc_platform.h>
 
 #include <asm/setup.h>
 #include <asm/sections.h>
@@ -287,7 +288,13 @@ void __init sme_encrypt_kernel(struct boot_params *bp)
 	unsigned long pgtable_area_len;
 	unsigned long decrypted_base;
 
-	if (!sme_active())
+	/*
+	 * This is early code, use an open coded check for SME instead of
+	 * using cc_platform_has(). This eliminates worries about removing
+	 * instrumentation or checking boot_cpu_data in the cc_platform_has()
+	 * function.
+	 */
+	if (!sme_get_me_mask() || sev_status & MSR_AMD64_SEV_ENABLED)
 		return;
 
 	/*
diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
index 31b5856010cb..c878c5ee5a4c 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/cc_platform.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 (cc_platform_has(CC_ATTR_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 (cc_platform_has(CC_ATTR_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 2a822b229bd0..c6c53e18dace 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/cc_platform.h>
 #include <asm/pci-direct.h>
 #include <asm/iommu.h>
 #include <asm/apic.h>
@@ -964,7 +964,7 @@ 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 = (cc_platform_has(CC_ATTR_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);
@@ -3032,7 +3032,8 @@ static int __init amd_iommu_init(void)
 
 static bool amd_iommu_sme_check(void)
 {
-	if (!sme_active() || (boot_cpu_data.x86 != 0x17))
+	if (!cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT) ||
+	    (boot_cpu_data.x86 != 0x17))
 		return true;
 
 	/* For Fam17h, a specific level of support is required */
-- 
2.29.2

[PATCH 6/8] x86/sev: Replace occurrences of sev_active() with cc_platform_has()

[Borislav Petkov]

From: Tom Lendacky <thomas.lendacky@amd.com>

Replace uses of sev_active() with the more generic cc_platform_has()
using CC_ATTR_GUEST_MEM_ENCRYPT. If future support is added for other
memory encryption technologies, the use of CC_ATTR_GUEST_MEM_ENCRYPT
can be updated, as required.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
---
 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 |  4 ++--
 arch/x86/kvm/svm/svm.c             |  3 ++-
 arch/x86/mm/ioremap.c              |  6 +++---
 arch/x86/mm/mem_encrypt.c          | 21 ++++++++-------------
 arch/x86/platform/efi/efi_64.c     |  9 +++++----
 9 files changed, 27 insertions(+), 29 deletions(-)

diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index 63c5b99ccae5..a5a58ccd1ee3 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h
@@ -51,7 +51,6 @@ 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);
 
 #define __bss_decrypted __section(".bss..decrypted")
@@ -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 int __init
diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c
index 045e82e8945b..a7f617a3981d 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/cc_platform.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,
+				cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT));
 }
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index b656456c3a94..8863d1941f1b 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/cc_platform.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 (!cc_platform_has(CC_ATTR_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..fc3930c5db1b 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/cc_platform.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 (cc_platform_has(CC_ATTR_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 7040c0fa921c..f5da4a18070a 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 (cc_platform_has(CC_ATTR_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 (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
 		info.page_flag   |= _PAGE_ENC;
 		info.kernpg_flag |= _PAGE_ENC;
 	}
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 05e8d4d27969..a2f78a8cfdaa 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/cc_platform.h>
 
 #include <asm/apic.h>
 #include <asm/perf_event.h>
@@ -455,7 +456,7 @@ static int has_svm(void)
 		return 0;
 	}
 
-	if (sev_active()) {
+	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
 		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 a7250fa3d45f..b59a5cbc6bc5 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 (!cc_platform_has(CC_ATTR_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 (!cc_platform_has(CC_ATTR_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 (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
 			break;
 		fallthrough;
 
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 2163485a74e1..932007a6913b 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 (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
 		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 (!cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
 		return;
 
 	/*
@@ -364,8 +364,8 @@ 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.
+ * cc_platform_has() function is used for this.  When a distinction isn't
+ * needed, the CC_ATTR_MEM_ENCRYPT attribute can be used.
  *
  * The trampoline code is a good example for this requirement.  Before
  * paging is activated, SME will access all memory as decrypted, but SEV
@@ -373,11 +373,6 @@ 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)
-{
-	return sev_status & MSR_AMD64_SEV_ENABLED;
-}
-EXPORT_SYMBOL_GPL(sev_active);
 
 /* Needs to be called from non-instrumentable code */
 bool noinstr sev_es_active(void)
@@ -391,7 +386,7 @@ bool force_dma_unencrypted(struct device *dev)
 	/*
 	 * For SEV, all DMA must be to unencrypted addresses.
 	 */
-	if (sev_active())
+	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
 		return true;
 
 	/*
@@ -450,7 +445,7 @@ static void print_mem_encrypt_feature_info(void)
 	}
 
 	/* Secure Encrypted Virtualization */
-	if (sev_active())
+	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
 		pr_cont(" SEV");
 
 	/* Encrypted Register State */
@@ -473,7 +468,7 @@ 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 (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT) && !sev_es_active())
 		static_branch_enable(&sev_enable_key);
 
 	print_mem_encrypt_feature_info();
@@ -481,6 +476,6 @@ void __init mem_encrypt_init(void)
 
 int arch_has_restricted_virtio_memory_access(void)
 {
-	return sev_active();
+	return cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT);
 }
 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..1f3675453a57 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/cc_platform.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 (cc_platform_has(CC_ATTR_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 (cc_platform_has(CC_ATTR_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 (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
 			pf |= _PAGE_ENC;
 
 		efi_update_mappings(md, pf);
-- 
2.29.2

[PATCH 7/8] x86/sev: Replace occurrences of sev_es_active() with cc_platform_has()

[Borislav Petkov]

From: Tom Lendacky <thomas.lendacky@amd.com>

Replace uses of sev_es_active() with the more generic cc_platform_has()
using CC_ATTR_GUEST_STATE_ENCRYPT. If future support is added for other
memory encyrption techonologies, the use of CC_ATTR_GUEST_STATE_ENCRYPT
can be updated, as required.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
---
 arch/x86/include/asm/mem_encrypt.h |  2 --
 arch/x86/kernel/sev.c              |  6 +++---
 arch/x86/mm/mem_encrypt.c          | 24 +++---------------------
 arch/x86/realmode/init.c           |  3 +--
 4 files changed, 7 insertions(+), 28 deletions(-)

diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index a5a58ccd1ee3..da14ede311aa 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h
@@ -51,7 +51,6 @@ 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);
 
 #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 int __init
 early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }
diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index a6895e440bc3..53a6837d354b 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/cc_platform.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 (!cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
 		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 (!cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
 		return;
 
 	if (!sev_es_check_cpu_features())
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 932007a6913b..2d04c39bea1d 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -361,25 +361,6 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size)
 	return early_set_memory_enc_dec(vaddr, size, true);
 }
 
-/*
- * SME and SEV are very similar but they are not the same, so there are
- * times that the kernel will need to distinguish between SME and SEV. The
- * cc_platform_has() function is used for this.  When a distinction isn't
- * needed, the CC_ATTR_MEM_ENCRYPT attribute can be used.
- *
- * The trampoline code is a good example for this requirement.  Before
- * paging is activated, SME will access all memory as decrypted, but SEV
- * will access all memory as encrypted.  So, when APs are being brought
- * up under SME the trampoline area cannot be encrypted, whereas under SEV
- * the trampoline area must be encrypted.
- */
-
-/* Needs to be called from non-instrumentable code */
-bool noinstr sev_es_active(void)
-{
-	return sev_status & MSR_AMD64_SEV_ES_ENABLED;
-}
-
 /* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */
 bool force_dma_unencrypted(struct device *dev)
 {
@@ -449,7 +430,7 @@ static void print_mem_encrypt_feature_info(void)
 		pr_cont(" SEV");
 
 	/* Encrypted Register State */
-	if (sev_es_active())
+	if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
 		pr_cont(" SEV-ES");
 
 	pr_cont("\n");
@@ -468,7 +449,8 @@ 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 (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT) && !sev_es_active())
+	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT) &&
+	    !cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
 		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 c878c5ee5a4c..4a3da7592b99 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/cc_platform.h>
 #include <linux/pgtable.h>
 
@@ -48,7 +47,7 @@ static void sme_sev_setup_real_mode(struct trampoline_header *th)
 	if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT))
 		th->flags |= TH_FLAGS_SME_ACTIVE;
 
-	if (sev_es_active()) {
+	if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) {
 		/*
 		 * Skip the call to verify_cpu() in secondary_startup_64 as it
 		 * will cause #VC exceptions when the AP can't handle them yet.
-- 
2.29.2

[PATCH 8/8] treewide: Replace the use of mem_encrypt_active() with cc_platform_has()

[Borislav Petkov]

From: Tom Lendacky <thomas.lendacky@amd.com>

Replace uses of mem_encrypt_active() with calls to cc_platform_has() with
the CC_ATTR_MEM_ENCRYPT attribute.

Remove the implementation of mem_encrypt_active() across all arches.

For s390, since the default implementation of the cc_platform_has()
matches the s390 implementation of mem_encrypt_active(), cc_platform_has()
does not need to be implemented in s390 (the config option
ARCH_HAS_CC_PLATFORM is not set).

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
---
 arch/powerpc/include/asm/mem_encrypt.h  | 5 -----
 arch/powerpc/platforms/pseries/svm.c    | 5 +++--
 arch/s390/include/asm/mem_encrypt.h     | 2 --
 arch/x86/include/asm/mem_encrypt.h      | 5 -----
 arch/x86/kernel/head64.c                | 9 +++++++--
 arch/x86/mm/ioremap.c                   | 4 ++--
 arch/x86/mm/mem_encrypt.c               | 2 +-
 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 +++---
 include/linux/mem_encrypt.h             | 4 ----
 kernel/dma/swiotlb.c                    | 4 ++--
 18 files changed, 36 insertions(+), 40 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();
diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c
index 87f001b4c4e4..c083ecbbae4d 100644
--- a/arch/powerpc/platforms/pseries/svm.c
+++ b/arch/powerpc/platforms/pseries/svm.c
@@ -8,6 +8,7 @@
 
 #include <linux/mm.h>
 #include <linux/memblock.h>
+#include <linux/cc_platform.h>
 #include <asm/machdep.h>
 #include <asm/svm.h>
 #include <asm/swiotlb.h>
@@ -63,7 +64,7 @@ void __init svm_swiotlb_init(void)
 
 int set_memory_encrypted(unsigned long addr, int numpages)
 {
-	if (!mem_encrypt_active())
+	if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT))
 		return 0;
 
 	if (!PAGE_ALIGNED(addr))
@@ -76,7 +77,7 @@ int set_memory_encrypted(unsigned long addr, int numpages)
 
 int set_memory_decrypted(unsigned long addr, int numpages)
 {
-	if (!mem_encrypt_active())
+	if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT))
 		return 0;
 
 	if (!PAGE_ALIGNED(addr))
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);
 
diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h
index da14ede311aa..2d4f5c17d79c 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h
@@ -96,11 +96,6 @@ 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;
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index de01903c3735..fc5371a7e9d1 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/cc_platform.h>
 #include <linux/pgtable.h>
 
 #include <asm/processor.h>
@@ -284,8 +284,13 @@ unsigned long __head __startup_64(unsigned long physaddr,
 	 * The bss section will be memset to zero later in the initialization so
 	 * there is no need to zero it after changing the memory encryption
 	 * attribute.
+	 *
+	 * This is early code, use an open coded check for SME instead of
+	 * using cc_platform_has(). This eliminates worries about removing
+	 * instrumentation or checking boot_cpu_data in the cc_platform_has()
+	 * function.
 	 */
-	if (mem_encrypt_active()) {
+	if (sme_get_me_mask()) {
 		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 b59a5cbc6bc5..026031b3b782 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 (!cc_platform_has(CC_ATTR_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 (!cc_platform_has(CC_ATTR_MEM_ENCRYPT))
 		return prot;
 
 	encrypted_prot = true;
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 2d04c39bea1d..23d54b810f08 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -400,7 +400,7 @@ 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 (cc_platform_has(CC_ATTR_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..527957586f3c 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/cc_platform.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 (!cc_platform_has(CC_ATTR_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 f18240f87387..7741195eb85e 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/cc_platform.h>
 
 #include "amdgpu.h"
 #include "amdgpu_irq.h"
@@ -1269,7 +1270,8 @@ 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 (cc_platform_has(CC_ATTR_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 30cc59fe6ef7..f19d9acbe959 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/cc_platform.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 (cc_platform_has(CC_ATTR_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 ab9a1750e1df..bfd71c86faa5 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/cc_platform.h>
 
 #include <drm/drm_aperture.h>
 #include <drm/drm_drv.h>
@@ -666,7 +666,7 @@ 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 (cc_platform_has(CC_ATTR_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 e50fb82a3030..2aceac7856e2 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/cc_platform.h>
 
 #include <asm/hypervisor.h>
 #include <drm/drm_ioctl.h>
@@ -160,7 +160,7 @@ 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 && !cc_platform_has(CC_ATTR_MEM_ENCRYPT)) {
 		unsigned long bp = channel->cookie_high;
 		u32 channel_id = (channel->channel_id << 16);
 
@@ -216,7 +216,7 @@ 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 && !cc_platform_has(CC_ATTR_MEM_ENCRYPT)) {
 		unsigned long bp = channel->cookie_low;
 		u32 channel_id = (channel->channel_id << 16);
 
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 1722bb161841..9e5da037d949 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/cc_platform.h>
 #include <asm/irq_remapping.h>
 #include <asm/io_apic.h>
 #include <asm/apic.h>
@@ -2238,7 +2239,7 @@ 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 (!cc_platform_has(CC_ATTR_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 a9e568276c99..13cbeb997cc1 100644
--- a/drivers/iommu/amd/iommu_v2.c
+++ b/drivers/iommu/amd/iommu_v2.c
@@ -17,6 +17,7 @@
 #include <linux/wait.h>
 #include <linux/pci.h>
 #include <linux/gfp.h>
+#include <linux/cc_platform.h>
 
 #include "amd_iommu.h"
 
@@ -742,7 +743,7 @@ 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 (cc_platform_has(CC_ATTR_MEM_ENCRYPT))
 		return -ENODEV;
 
 	if (!amd_iommu_v2_supported())
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3303d707bab4..e80261d17a49 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -25,6 +25,7 @@
 #include <linux/property.h>
 #include <linux/fsl/mc.h>
 #include <linux/module.h>
+#include <linux/cc_platform.h>
 #include <trace/events/iommu.h>
 
 static struct kset *iommu_group_kset;
@@ -130,7 +131,7 @@ static int __init iommu_subsys_init(void)
 		else
 			iommu_set_default_translated(false);
 
-		if (iommu_default_passthrough() && mem_encrypt_active()) {
+		if (iommu_default_passthrough() && cc_platform_has(CC_ATTR_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..cdbbf819d2d6 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/cc_platform.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, cc_platform_has(CC_ATTR_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, cc_platform_has(CC_ATTR_MEM_ENCRYPT));
 			if (tmp < 0)
 				return tmp;
 			buflen -= tsz;
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
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 87c40517e822..c4ca040fdb05 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/cc_platform.h>
 #include <linux/set_memory.h>
 #ifdef CONFIG_DEBUG_FS
 #include <linux/debugfs.h>
@@ -552,7 +552,7 @@ 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 (cc_platform_has(CC_ATTR_MEM_ENCRYPT))
 		pr_warn_once("Memory encryption is active and system is using DMA bounce buffers\n");
 
 	if (mapping_size > alloc_size) {
-- 
2.29.2

Re: [PATCH v4 0/8] Implement generic cc_platform_has() helper function

[Kuppuswamy, Sathyanarayanan]

On 9/28/21 12:10 PM, Borislav Petkov wrote:
> From: Borislav Petkov <bp@suse.de>
> 
> Hi all,
> 
> here's v4 of the cc_platform_has() patchset with feedback incorporated.
> 
> I'm going to route this through tip if there are no objections.

Intel CC support patch is not included in this series. You want me
to address the issue raised by Joerg before merging it?

> 
> Thx.
> 
> Tom Lendacky (8):
>    x86/ioremap: Selectively build arch override encryption functions
>    arch/cc: Introduce a function to check for confidential computing
>      features
>    x86/sev: Add an x86 version of cc_platform_has()
>    powerpc/pseries/svm: Add a powerpc version of cc_platform_has()
>    x86/sme: Replace occurrences of sme_active() with cc_platform_has()
>    x86/sev: Replace occurrences of sev_active() with cc_platform_has()
>    x86/sev: Replace occurrences of sev_es_active() with cc_platform_has()
>    treewide: Replace the use of mem_encrypt_active() with
>      cc_platform_has()
> 
>   arch/Kconfig                                 |  3 +
>   arch/powerpc/include/asm/mem_encrypt.h       |  5 --
>   arch/powerpc/platforms/pseries/Kconfig       |  1 +
>   arch/powerpc/platforms/pseries/Makefile      |  2 +
>   arch/powerpc/platforms/pseries/cc_platform.c | 26 ++++++
>   arch/powerpc/platforms/pseries/svm.c         |  5 +-
>   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           | 12 +--
>   arch/x86/kernel/Makefile                     |  6 ++
>   arch/x86/kernel/cc_platform.c                | 69 +++++++++++++++
>   arch/x86/kernel/crash_dump_64.c              |  4 +-
>   arch/x86/kernel/head64.c                     |  9 +-
>   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                    | 55 ++++--------
>   arch/x86/mm/mem_encrypt_identity.c           |  9 +-
>   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/cc_platform.h                  | 88 ++++++++++++++++++++
>   include/linux/mem_encrypt.h                  |  4 -
>   kernel/dma/swiotlb.c                         |  4 +-
>   40 files changed, 310 insertions(+), 129 deletions(-)
>   create mode 100644 arch/powerpc/platforms/pseries/cc_platform.c
>   create mode 100644 arch/x86/kernel/cc_platform.c
>   create mode 100644 include/linux/cc_platform.h
> 

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer

Re: [PATCH v4 0/8] Implement generic cc_platform_has() helper function

[Borislav Petkov]

On Tue, Sep 28, 2021 at 12:19:49PM -0700, Kuppuswamy, Sathyanarayanan wrote:
> Intel CC support patch is not included in this series. You want me
> to address the issue raised by Joerg before merging it?

Did you not see my email to you today:

https://lkml.kernel.org/r/YVL4ZUGhfsh1QfRX@zn.tnic

?

-- 
Regards/Gruss,
    Boris.

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

Re: [PATCH v4 0/8] Implement generic cc_platform_has() helper function

[Kuppuswamy, Sathyanarayanan]

On 9/28/21 1:31 PM, Borislav Petkov wrote:
> On Tue, Sep 28, 2021 at 12:19:49PM -0700, Kuppuswamy, Sathyanarayanan wrote:
>> Intel CC support patch is not included in this series. You want me
>> to address the issue raised by Joerg before merging it?
> 
> Did you not see my email to you today:
> 
> https://lkml.kernel.org/r/YVL4ZUGhfsh1QfRX@zn.tnic

Just read it. If you want to use cpuid_has_tdx_guest() directly in
cc_platform_has(), then you want to rename intel_cc_platform_has() to
tdx_cc_platform_has()?

> 
> ?
> 

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer

Re: [PATCH v4 0/8] Implement generic cc_platform_has() helper function

[Borislav Petkov]

On Tue, Sep 28, 2021 at 01:48:46PM -0700, Kuppuswamy, Sathyanarayanan wrote:
> Just read it. If you want to use cpuid_has_tdx_guest() directly in
> cc_platform_has(), then you want to rename intel_cc_platform_has() to
> tdx_cc_platform_has()?

Why?

You simply do:

	if (cpuid_has_tdx_guest())
		intel_cc_platform_has(...);

and lemme paste from that mail: " ...you should use
cpuid_has_tdx_guest() instead but cache its result so that you don't
call CPUID each time the kernel executes cc_platform_has()."

Makes sense?

-- 
Regards/Gruss,
    Boris.

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

Re: [PATCH v4 0/8] Implement generic cc_platform_has() helper function

[Kuppuswamy, Sathyanarayanan]

On 9/28/21 1:58 PM, Borislav Petkov wrote:
> On Tue, Sep 28, 2021 at 01:48:46PM -0700, Kuppuswamy, Sathyanarayanan wrote:
>> Just read it. If you want to use cpuid_has_tdx_guest() directly in
>> cc_platform_has(), then you want to rename intel_cc_platform_has() to
>> tdx_cc_platform_has()?
> 
> Why?
> 
> You simply do:
> 
> 	if (cpuid_has_tdx_guest())
> 		intel_cc_platform_has(...);
> 
> and lemme paste from that mail: " ...you should use
> cpuid_has_tdx_guest() instead but cache its result so that you don't
> call CPUID each time the kernel executes cc_platform_has()."
> 
> Makes sense?

Yes. But, since the check is related to TDX, I just want to confirm whether
you are fine with naming the function as intel_*().

Since this patch is going to have dependency on TDX code, I will include
this patch in TDX patch set.

> 

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer

Re: [PATCH v4 0/8] Implement generic cc_platform_has() helper function

[Borislav Petkov]

On Tue, Sep 28, 2021 at 02:01:57PM -0700, Kuppuswamy, Sathyanarayanan wrote:
> Yes. But, since the check is related to TDX, I just want to confirm whether
> you are fine with naming the function as intel_*().

Why is this such a big of a deal?!

There's amd_cc_platform_has() and intel_cc_platform_has() will be the
corresponding Intel version.

> Since this patch is going to have dependency on TDX code, I will include
> this patch in TDX patch set.

Ok.

-- 
Regards/Gruss,
    Boris.

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