Merge tag 'efi-next-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

bf243102 · Linus Torvalds <[email protected]> · 2022-05-23 11:27:24 -07:00

Pull EFI updates from Ard Biesheuvel:

 - Allow runtime services to be re-enabled at boot on RT kernels.

 - Provide access to secrets injected into the boot image by CoCo
   hypervisors (COnfidential COmputing)

 - Use DXE services on x86 to make the boot image executable after
   relocation, if needed.

 - Prefer mirrored memory for randomized allocations.

 - Only randomize the placement of the kernel image on arm64 if the
   loader has not already done so.

 - Add support for obtaining the boot hartid from EFI on RISC-V.

* tag 'efi-next-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  riscv/efi_stub: Add support for RISCV_EFI_BOOT_PROTOCOL
  efi: stub: prefer mirrored memory for randomized allocations
  efi/arm64: libstub: run image in place if randomized by the loader
  efi: libstub: pass image handle to handle_kernel_image()
  efi: x86: Set the NX-compatibility flag in the PE header
  efi: libstub: ensure allocated memory to be executable
  efi: libstub: declare DXE services table
  efi: Add missing prototype for efi_capsule_setup_info
  docs: security: Add secrets/coco documentation
  efi: Register efi_secret platform device if EFI secret area is declared
  virt: Add efi_secret module to expose confidential computing secrets
  efi: Save location of EFI confidential computing area
  efi: Allow to enable EFI runtime services by default on RT

Commit: bf2431021c8cfe52c866d7bf640ced03a35ebe91
Parents: 4b0986a3 · 3f68e695

Merge commit. Changes below are compared with the first parent: 4b0986a3.

Changes

22 files changed · +876 −20

File	Status	Add	Del	Content
Documentation/ABI/testing/securityfs-secrets-coco	added	+51	−0	View file
Documentation/security/index.rst	modified	+1	−0	View file
Documentation/security/secrets/coco.rst	added	+103	−0	View file
Documentation/security/secrets/index.rst	added	+9	−0	View file
arch/x86/boot/header.S	modified	+4	−0	View file
arch/x86/include/asm/efi.h	modified	+5	−0	View file
arch/x86/platform/efi/efi.c	modified	+3	−0	View file
drivers/firmware/efi/Kconfig	modified	+43	−0	View file
drivers/firmware/efi/efi.c	modified	+12	−1	View file
drivers/firmware/efi/libstub/arm32-stub.c	modified	+2	−1	View file
drivers/firmware/efi/libstub/arm64-stub.c	modified	+11	−4	View file
drivers/firmware/efi/libstub/efi-stub.c	modified	+1	−1	View file
drivers/firmware/efi/libstub/efistub.h	modified	+83	−1	View file
drivers/firmware/efi/libstub/randomalloc.c	modified	+11	−0	View file
drivers/firmware/efi/libstub/riscv-stub.c	modified	+25	−7	View file
drivers/firmware/efi/libstub/x86-stub.c	modified	+114	−5	View file
drivers/virt/Kconfig	modified	+3	−0	View file
drivers/virt/Makefile	modified	+1	−0	View file
drivers/virt/coco/efi_secret/Kconfig	added	+16	−0	View file
drivers/virt/coco/efi_secret/Makefile	added	+2	−0	View file
drivers/virt/coco/efi_secret/efi_secret.c	added	+349	−0	View file
include/linux/efi.h	modified	+27	−0	View file

Only the first 600 diff lines are shown. Download the complete patch.

Documentation/ABI/testing/securityfs-secrets-coco

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diff --git a/Documentation/ABI/testing/securityfs-secrets-coco b/Documentation/ABI/testing/securityfs-secrets-coco
new file mode 100644
index 0000000..f2b6909
--- /dev/null
+++ b/Documentation/ABI/testing/securityfs-secrets-coco
@@ -0,0 +1,51 @@
+What:		security/secrets/coco
+Date:		February 2022
+Contact:	Dov Murik <[email protected]>
+Description:
+		Exposes confidential computing (coco) EFI secrets to
+		userspace via securityfs.
+
+		EFI can declare memory area used by confidential computing
+		platforms (such as AMD SEV and SEV-ES) for secret injection by
+		the Guest Owner during VM's launch.  The secrets are encrypted
+		by the Guest Owner and decrypted inside the trusted enclave,
+		and therefore are not readable by the untrusted host.
+
+		The efi_secret module exposes the secrets to userspace.  Each
+		secret appears as a file under <securityfs>/secrets/coco,
+		where the filename is the GUID of the entry in the secrets
+		table.  This module is loaded automatically by the EFI driver
+		if the EFI secret area is populated.
+
+		Two operations are supported for the files: read and unlink.
+		Reading the file returns the content of secret entry.
+		Unlinking the file overwrites the secret data with zeroes and
+		removes the entry from the filesystem.  A secret cannot be read
+		after it has been unlinked.
+
+		For example, listing the available secrets::
+
+		  # modprobe efi_secret
+		  # ls -l /sys/kernel/security/secrets/coco
+		  -r--r----- 1 root root 0 Jun 28 11:54 736870e5-84f0-4973-92ec-06879ce3da0b
+		  -r--r----- 1 root root 0 Jun 28 11:54 83c83f7f-1356-4975-8b7e-d3a0b54312c6
+		  -r--r----- 1 root root 0 Jun 28 11:54 9553f55d-3da2-43ee-ab5d-ff17f78864d2
+		  -r--r----- 1 root root 0 Jun 28 11:54 e6f5a162-d67f-4750-a67c-5d065f2a9910
+
+		Reading the secret data by reading a file::
+
+		  # cat /sys/kernel/security/secrets/coco/e6f5a162-d67f-4750-a67c-5d065f2a9910
+		  the-content-of-the-secret-data
+
+		Wiping a secret by unlinking a file::
+
+		  # rm /sys/kernel/security/secrets/coco/e6f5a162-d67f-4750-a67c-5d065f2a9910
+		  # ls -l /sys/kernel/security/secrets/coco
+		  -r--r----- 1 root root 0 Jun 28 11:54 736870e5-84f0-4973-92ec-06879ce3da0b
+		  -r--r----- 1 root root 0 Jun 28 11:54 83c83f7f-1356-4975-8b7e-d3a0b54312c6
+		  -r--r----- 1 root root 0 Jun 28 11:54 9553f55d-3da2-43ee-ab5d-ff17f78864d2
+
+		Note: The binary format of the secrets table injected by the
+		Guest Owner is described in
+		drivers/virt/coco/efi_secret/efi_secret.c under "Structure of
+		the EFI secret area".

Documentation/security/index.rst

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diff --git a/Documentation/security/index.rst b/Documentation/security/index.rst
index 16335de..6ed8d2f 100644
--- a/Documentation/security/index.rst
+++ b/Documentation/security/index.rst
@@ -17,3 +17,4 @@ Security Documentation
    tpm/index
    digsig
    landlock
+   secrets/index

Documentation/security/secrets/coco.rst

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diff --git a/Documentation/security/secrets/coco.rst b/Documentation/security/secrets/coco.rst
new file mode 100644
index 0000000..262e7ab
--- /dev/null
+++ b/Documentation/security/secrets/coco.rst
@@ -0,0 +1,103 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==============================
+Confidential Computing secrets
+==============================
+
+This document describes how Confidential Computing secret injection is handled
+from the firmware to the operating system, in the EFI driver and the efi_secret
+kernel module.
+
+
+Introduction
+============
+
+Confidential Computing (coco) hardware such as AMD SEV (Secure Encrypted
+Virtualization) allows guest owners to inject secrets into the VMs
+memory without the host/hypervisor being able to read them.  In SEV,
+secret injection is performed early in the VM launch process, before the
+guest starts running.
+
+The efi_secret kernel module allows userspace applications to access these
+secrets via securityfs.
+
+
+Secret data flow
+================
+
+The guest firmware may reserve a designated memory area for secret injection,
+and publish its location (base GPA and length) in the EFI configuration table
+under a ``LINUX_EFI_COCO_SECRET_AREA_GUID`` entry
+(``adf956ad-e98c-484c-ae11-b51c7d336447``).  This memory area should be marked
+by the firmware as ``EFI_RESERVED_TYPE``, and therefore the kernel should not
+be use it for its own purposes.
+
+During the VM's launch, the virtual machine manager may inject a secret to that
+area.  In AMD SEV and SEV-ES this is performed using the
+``KVM_SEV_LAUNCH_SECRET`` command (see [sev]_).  The strucutre of the injected
+Guest Owner secret data should be a GUIDed table of secret values; the binary
+format is described in ``drivers/virt/coco/efi_secret/efi_secret.c`` under
+"Structure of the EFI secret area".
+
+On kernel start, the kernel's EFI driver saves the location of the secret area
+(taken from the EFI configuration table) in the ``efi.coco_secret`` field.
+Later it checks if the secret area is populated: it maps the area and checks
+whether its content begins with ``EFI_SECRET_TABLE_HEADER_GUID``
+(``1e74f542-71dd-4d66-963e-ef4287ff173b``).  If the secret area is populated,
+the EFI driver will autoload the efi_secret kernel module, which exposes the
+secrets to userspace applications via securityfs.  The details of the
+efi_secret filesystem interface are in [secrets-coco-abi]_.
+
+
+Application usage example
+=========================
+
+Consider a guest performing computations on encrypted files.  The Guest Owner
+provides the decryption key (= secret) using the secret injection mechanism.
+The guest application reads the secret from the efi_secret filesystem and
+proceeds to decrypt the files into memory and then performs the needed
+computations on the content.
+
+In this example, the host can't read the files from the disk image
+because they are encrypted.  Host can't read the decryption key because
+it is passed using the secret injection mechanism (= secure channel).
+Host can't read the decrypted content from memory because it's a
+confidential (memory-encrypted) guest.
+
+Here is a simple example for usage of the efi_secret module in a guest
+to which an EFI secret area with 4 secrets was injected during launch::
+
+	# ls -la /sys/kernel/security/secrets/coco
+	total 0
+	drwxr-xr-x 2 root root 0 Jun 28 11:54 .
+	drwxr-xr-x 3 root root 0 Jun 28 11:54 ..
+	-r--r----- 1 root root 0 Jun 28 11:54 736870e5-84f0-4973-92ec-06879ce3da0b
+	-r--r----- 1 root root 0 Jun 28 11:54 83c83f7f-1356-4975-8b7e-d3a0b54312c6
+	-r--r----- 1 root root 0 Jun 28 11:54 9553f55d-3da2-43ee-ab5d-ff17f78864d2
+	-r--r----- 1 root root 0 Jun 28 11:54 e6f5a162-d67f-4750-a67c-5d065f2a9910
+
+	# hd /sys/kernel/security/secrets/coco/e6f5a162-d67f-4750-a67c-5d065f2a9910
+	00000000  74 68 65 73 65 2d 61 72  65 2d 74 68 65 2d 6b 61  |these-are-the-ka|
+	00000010  74 61 2d 73 65 63 72 65  74 73 00 01 02 03 04 05  |ta-secrets......|
+	00000020  06 07                                             |..|
+	00000022
+
+	# rm /sys/kernel/security/secrets/coco/e6f5a162-d67f-4750-a67c-5d065f2a9910
+
+	# ls -la /sys/kernel/security/secrets/coco
+	total 0
+	drwxr-xr-x 2 root root 0 Jun 28 11:55 .
+	drwxr-xr-x 3 root root 0 Jun 28 11:54 ..
+	-r--r----- 1 root root 0 Jun 28 11:54 736870e5-84f0-4973-92ec-06879ce3da0b
+	-r--r----- 1 root root 0 Jun 28 11:54 83c83f7f-1356-4975-8b7e-d3a0b54312c6
+	-r--r----- 1 root root 0 Jun 28 11:54 9553f55d-3da2-43ee-ab5d-ff17f78864d2
+
+
+References
+==========
+
+See [sev-api-spec]_ for more info regarding SEV ``LAUNCH_SECRET`` operation.
+
+.. [sev] Documentation/virt/kvm/amd-memory-encryption.rst
+.. [secrets-coco-abi] Documentation/ABI/testing/securityfs-secrets-coco
+.. [sev-api-spec] https://www.amd.com/system/files/TechDocs/55766_SEV-KM_API_Specification.pdf

Documentation/security/secrets/index.rst

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diff --git a/Documentation/security/secrets/index.rst b/Documentation/security/secrets/index.rst
new file mode 100644
index 0000000..ced34e9
--- /dev/null
+++ b/Documentation/security/secrets/index.rst
@@ -0,0 +1,9 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=====================
+Secrets documentation
+=====================
+
+.. toctree::
+
+   coco

arch/x86/boot/header.S

View file

diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 6dbd7e9..0352e45 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -163,7 +163,11 @@ extra_header_fields:
 	.long	0x200				# SizeOfHeaders
 	.long	0				# CheckSum
 	.word	IMAGE_SUBSYSTEM_EFI_APPLICATION	# Subsystem (EFI application)
+#ifdef CONFIG_DXE_MEM_ATTRIBUTES
+	.word	IMAGE_DLL_CHARACTERISTICS_NX_COMPAT	# DllCharacteristics
+#else
 	.word	0				# DllCharacteristics
+#endif
 #ifdef CONFIG_X86_32
 	.long	0				# SizeOfStackReserve
 	.long	0				# SizeOfStackCommit

arch/x86/include/asm/efi.h

View file

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 98938a6..bed74a0 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -357,6 +357,11 @@ static inline u32 efi64_convert_status(efi_status_t status)
 						   runtime),		\
 				    func, __VA_ARGS__))
 
+#define efi_dxe_call(func, ...)						\
+	(efi_is_native()						\
+		? efi_dxe_table->func(__VA_ARGS__)			\
+		: __efi64_thunk_map(efi_dxe_table, func, __VA_ARGS__))
+
 #else /* CONFIG_EFI_MIXED */
 
 static inline bool efi_is_64bit(void)

arch/x86/platform/efi/efi.c

View file

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 147c30a..1591d67 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -93,6 +93,9 @@ static const unsigned long * const efi_tables[] = {
 #ifdef CONFIG_LOAD_UEFI_KEYS
 	&efi.mokvar_table,
 #endif
+#ifdef CONFIG_EFI_COCO_SECRET
+	&efi.coco_secret,
+#endif
 };
 
 u64 efi_setup;		/* efi setup_data physical address */

drivers/firmware/efi/Kconfig

View file

diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 2c3dac5..4720ba9 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -91,6 +91,18 @@ config EFI_SOFT_RESERVE
 
 	  If unsure, say Y.
 
+config EFI_DXE_MEM_ATTRIBUTES
+	bool "Adjust memory attributes in EFISTUB"
+	depends on EFI && EFI_STUB && X86
+	default y
+	help
+	  UEFI specification does not guarantee all memory to be
+	  accessible for both write and execute as the kernel expects
+	  it to be.
+	  Use DXE services to check and alter memory protection
+	  attributes during boot via EFISTUB to ensure that memory
+	  ranges used by the kernel are writable and executable.
+
 config EFI_PARAMS_FROM_FDT
 	bool
 	help
@@ -284,3 +296,34 @@ config EFI_CUSTOM_SSDT_OVERLAYS
 
 	  See Documentation/admin-guide/acpi/ssdt-overlays.rst for more
 	  information.
+
+config EFI_DISABLE_RUNTIME
+	bool "Disable EFI runtime services support by default"
+	default y if PREEMPT_RT
+	help
+	  Allow to disable the EFI runtime services support by default. This can
+	  already be achieved by using the efi=noruntime option, but it could be
+	  useful to have this default without any kernel command line parameter.
+
+	  The EFI runtime services are disabled by default when PREEMPT_RT is
+	  enabled, because measurements have shown that some EFI functions calls
+	  might take too much time to complete, causing large latencies which is
+	  an issue for Real-Time kernels.
+
+	  This default can be overridden by using the efi=runtime option.
+
+config EFI_COCO_SECRET
+	bool "EFI Confidential Computing Secret Area Support"
+	depends on EFI
+	help
+	  Confidential Computing platforms (such as AMD SEV) allow the
+	  Guest Owner to securely inject secrets during guest VM launch.
+	  The secrets are placed in a designated EFI reserved memory area.
+
+	  In order to use the secrets in the kernel, the location of the secret
+	  area (as published in the EFI config table) must be kept.
+
+	  If you say Y here, the address of the EFI secret area will be kept
+	  for usage inside the kernel.  This will allow the
+	  virt/coco/efi_secret module to access the secrets, which in turn
+	  allows userspace programs to access the injected secrets.

drivers/firmware/efi/efi.c

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diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 5502e17..860534b 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -46,6 +46,9 @@ struct efi __read_mostly efi = {
 #ifdef CONFIG_LOAD_UEFI_KEYS
 	.mokvar_table		= EFI_INVALID_TABLE_ADDR,
 #endif
+#ifdef CONFIG_EFI_COCO_SECRET
+	.coco_secret		= EFI_INVALID_TABLE_ADDR,
+#endif
 };
 EXPORT_SYMBOL(efi);
 
@@ -66,7 +69,7 @@ struct mm_struct efi_mm = {
 
 struct workqueue_struct *efi_rts_wq;
 
-static bool disable_runtime = IS_ENABLED(CONFIG_PREEMPT_RT);
+static bool disable_runtime = IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME);
 static int __init setup_noefi(char *arg)
 {
 	disable_runtime = true;
@@ -422,6 +425,11 @@ static int __init efisubsys_init(void)
 	if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
 		efi_debugfs_init();
 
+#ifdef CONFIG_EFI_COCO_SECRET
+	if (efi.coco_secret != EFI_INVALID_TABLE_ADDR)
+		platform_device_register_simple("efi_secret", 0, NULL, 0);
+#endif
+
 	return 0;
 
 err_remove_group:
@@ -529,6 +537,9 @@ static const efi_config_table_type_t common_tables[] __initconst = {
 #ifdef CONFIG_LOAD_UEFI_KEYS
 	{LINUX_EFI_MOK_VARIABLE_TABLE_GUID,	&efi.mokvar_table,	"MOKvar"	},
 #endif
+#ifdef CONFIG_EFI_COCO_SECRET
+	{LINUX_EFI_COCO_SECRET_AREA_GUID,	&efi.coco_secret,	"CocoSecret"	},
+#endif
 	{},
 };
 

drivers/firmware/efi/libstub/arm32-stub.c

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diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c
index 4b5b240..0131e3a 100644
--- a/drivers/firmware/efi/libstub/arm32-stub.c
+++ b/drivers/firmware/efi/libstub/arm32-stub.c
@@ -117,7 +117,8 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 				 unsigned long *image_size,
 				 unsigned long *reserve_addr,
 				 unsigned long *reserve_size,
-				 efi_loaded_image_t *image)
+				 efi_loaded_image_t *image,
+				 efi_handle_t image_handle)
 {
 	const int slack = TEXT_OFFSET - 5 * PAGE_SIZE;
 	int alloc_size = MAX_UNCOMP_KERNEL_SIZE + EFI_PHYS_ALIGN;

drivers/firmware/efi/libstub/arm64-stub.c

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diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
index 9cc5560..577173e 100644
--- a/drivers/firmware/efi/libstub/arm64-stub.c
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -83,7 +83,8 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 				 unsigned long *image_size,
 				 unsigned long *reserve_addr,
 				 unsigned long *reserve_size,
-				 efi_loaded_image_t *image)
+				 efi_loaded_image_t *image,
+				 efi_handle_t image_handle)
 {
 	efi_status_t status;
 	unsigned long kernel_size, kernel_memsize = 0;
@@ -100,7 +101,15 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 	u64 min_kimg_align = efi_nokaslr ? MIN_KIMG_ALIGN : EFI_KIMG_ALIGN;
 
 	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
-		if (!efi_nokaslr) {
+		efi_guid_t li_fixed_proto = LINUX_EFI_LOADED_IMAGE_FIXED_GUID;
+		void *p;
+
+		if (efi_nokaslr) {
+			efi_info("KASLR disabled on kernel command line\n");
+		} else if (efi_bs_call(handle_protocol, image_handle,
+				       &li_fixed_proto, &p) == EFI_SUCCESS) {
+			efi_info("Image placement fixed by loader\n");
+		} else {
 			status = efi_get_random_bytes(sizeof(phys_seed),
 						      (u8 *)&phys_seed);
 			if (status == EFI_NOT_FOUND) {
@@ -111,8 +120,6 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 					status);
 				efi_nokaslr = true;
 			}
-		} else {
-			efi_info("KASLR disabled on kernel command line\n");
 		}
 	}
 

drivers/firmware/efi/libstub/efi-stub.c

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diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
index da93864..f515394 100644
--- a/drivers/firmware/efi/libstub/efi-stub.c
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -198,7 +198,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 	status = handle_kernel_image(&image_addr, &image_size,
 				     &reserve_addr,
 				     &reserve_size,
-				     image);
+				     image, handle);
 	if (status != EFI_SUCCESS) {
 		efi_err("Failed to relocate kernel\n");
 		goto fail_free_screeninfo;

drivers/firmware/efi/libstub/efistub.h

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diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index edb77b0..b0ae0a4 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -36,6 +36,9 @@ extern bool efi_novamap;
 
 extern const efi_system_table_t *efi_system_table;
 
+typedef union efi_dxe_services_table efi_dxe_services_table_t;
+extern const efi_dxe_services_table_t *efi_dxe_table;
+
 efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 				   efi_system_table_t *sys_table_arg);
 
@@ -44,6 +47,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 #define efi_is_native()		(true)
 #define efi_bs_call(func, ...)	efi_system_table->boottime->func(__VA_ARGS__)
 #define efi_rt_call(func, ...)	efi_system_table->runtime->func(__VA_ARGS__)
+#define efi_dxe_call(func, ...)	efi_dxe_table->func(__VA_ARGS__)
 #define efi_table_attr(inst, attr)	(inst->attr)
 #define efi_call_proto(inst, func, ...) inst->func(inst, ##__VA_ARGS__)
 
@@ -329,6 +333,76 @@ union efi_boot_services {
 	} mixed_mode;
 };
 
+typedef enum {
+	EfiGcdMemoryTypeNonExistent,
+	EfiGcdMemoryTypeReserved,
+	EfiGcdMemoryTypeSystemMemory,
+	EfiGcdMemoryTypeMemoryMappedIo,
+	EfiGcdMemoryTypePersistent,
+	EfiGcdMemoryTypeMoreReliable,
+	EfiGcdMemoryTypeMaximum
+} efi_gcd_memory_type_t;
+
+typedef struct {
+	efi_physical_addr_t base_address;
+	u64 length;
+	u64 capabilities;
+	u64 attributes;
+	efi_gcd_memory_type_t gcd_memory_type;
+	void *image_handle;
+	void *device_handle;
+} efi_gcd_memory_space_desc_t;
+
+/*
+ * EFI DXE Services table
+ */
+union efi_dxe_services_table {
+	struct {
+		efi_table_hdr_t hdr;
+		void *add_memory_space;
+		void *allocate_memory_space;
+		void *free_memory_space;
+		void *remove_memory_space;
+		efi_status_t (__efiapi *get_memory_space_descriptor)(efi_physical_addr_t,
+								     efi_gcd_memory_space_desc_t *);
+		efi_status_t (__efiapi *set_memory_space_attributes)(efi_physical_addr_t,
+								     u64, u64);
+		void *get_memory_space_map;
+		void *add_io_space;
+		void *allocate_io_space;
+		void *free_io_space;
+		void *remove_io_space;
+		void *get_io_space_descriptor;
+		void *get_io_space_map;
+		void *dispatch;
+		void *schedule;
+		void *trust;
+		void *process_firmware_volume;
+		void *set_memory_space_capabilities;
+	};
+	struct {
+		efi_table_hdr_t hdr;
+		u32 add_memory_space;
+		u32 allocate_memory_space;
+		u32 free_memory_space;
+		u32 remove_memory_space;
+		u32 get_memory_space_descriptor;
+		u32 set_memory_space_attributes;
+		u32 get_memory_space_map;
+		u32 add_io_space;
+		u32 allocate_io_space;
+		u32 free_io_space;
+		u32 remove_io_space;
+		u32 get_io_space_descriptor;
+		u32 get_io_space_map;
+		u32 dispatch;
+		u32 schedule;
+		u32 trust;
+		u32 process_firmware_volume;
+		u32 set_memory_space_capabilities;
+	} mixed_mode;
+};
+
 typedef union efi_uga_draw_protocol efi_uga_draw_protocol_t;
 
 union efi_uga_draw_protocol {
@@ -720,6 +794,13 @@ union efi_tcg2_protocol {
 	} mixed_mode;
 };
 
+struct riscv_efi_boot_protocol {
+	u64 revision;
+
+	efi_status_t (__efiapi *get_boot_hartid)(struct riscv_efi_boot_protocol *,
+						 unsigned long *boot_hartid);
+};
+
 typedef union efi_load_file_protocol efi_load_file_protocol_t;
 typedef union efi_load_file_protocol efi_load_file2_protocol_t;
 
@@ -865,7 +946,8 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 				 unsigned long *image_size,
 				 unsigned long *reserve_addr,
 				 unsigned long *reserve_size,
-				 efi_loaded_image_t *image);
+				 efi_loaded_image_t *image,
+				 efi_handle_t image_handle);
 
 asmlinkage void __noreturn efi_enter_kernel(unsigned long entrypoint,
 					    unsigned long fdt_addr,

drivers/firmware/efi/libstub/randomalloc.c

View file

diff --git a/drivers/firmware/efi/libstub/randomalloc.c b/drivers/firmware/efi/libstub/randomalloc.c
index 724155b..715f374 100644
--- a/drivers/firmware/efi/libstub/randomalloc.c
+++ b/drivers/firmware/efi/libstub/randomalloc.c
@@ -56,6 +56,7 @@ efi_status_t efi_random_alloc(unsigned long size,
 			      unsigned long random_seed)
 {
 	unsigned long map_size, desc_size, total_slots = 0, target_slot;
+	unsigned long total_mirrored_slots = 0;
 	unsigned long buff_size;
 	efi_status_t status;
 	efi_memory_desc_t *memory_map;
@@ -86,8 +87,14 @@ efi_status_t efi_random_alloc(unsigned long size,
 		slots = get_entry_num_slots(md, size, ilog2(align));
 		MD_NUM_SLOTS(md) = slots;
 		total_slots += slots;
+		if (md->attribute & EFI_MEMORY_MORE_RELIABLE)
+			total_mirrored_slots += slots;
 	}
 
+	/* consider only mirrored slots for randomization if any exist */
+	if (total_mirrored_slots > 0)
+		total_slots = total_mirrored_slots;
+
 	/* find a random number between 0 and total_slots */
 	target_slot = (total_slots * (u64)(random_seed & U32_MAX)) >> 32;
 
@@ -107,6 +114,10 @@ efi_status_t efi_random_alloc(unsigned long size,
 		efi_physical_addr_t target;
 		unsigned long pages;
 
+		if (total_mirrored_slots > 0 &&
+		    !(md->attribute & EFI_MEMORY_MORE_RELIABLE))
+			continue;
+
 		if (target_slot >= MD_NUM_SLOTS(md)) {
 			target_slot -= MD_NUM_SLOTS(md);
 			continue;

drivers/firmware/efi/libstub/riscv-stub.c

View file

diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c
index 9c46084..9e85e58 100644
--- a/drivers/firmware/efi/libstub/riscv-stub.c
+++ b/drivers/firmware/efi/libstub/riscv-stub.c
@@ -21,9 +21,9 @@
 #define MIN_KIMG_ALIGN		SZ_4M
 #endif
 
-typedef void __noreturn (*jump_kernel_func)(unsigned int, unsigned long);
+typedef void __noreturn (*jump_kernel_func)(unsigned long, unsigned long);
 
-static u32 hartid;
+static unsigned long hartid;
 
 static int get_boot_hartid_from_fdt(void)
 {
@@ -47,14 +47,31 @@ static int get_boot_hartid_from_fdt(void)
 	return 0;
 }
 
+static efi_status_t get_boot_hartid_from_efi(void)
+{
+	efi_guid_t boot_protocol_guid = RISCV_EFI_BOOT_PROTOCOL_GUID;
+	struct riscv_efi_boot_protocol *boot_protocol;
+	efi_status_t status;
+
+	status = efi_bs_call(locate_protocol, &boot_protocol_guid, NULL,
+			     (void **)&boot_protocol);
+	if (status != EFI_SUCCESS)
+		return status;
+	return efi_call_proto(boot_protocol, get_boot_hartid, &hartid);
+}
+