Merge tag 'efi-next-for-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI updates from Ard Biesheuvel:
 "Another fairly sizable pull request, by EFI subsystem standards.

  Most of the work was done by me, some of it in collaboration with the
  distro and bootloader folks (GRUB, systemd-boot), where the main focus
  has been on removing pointless per-arch differences in the way EFI
  boots a Linux kernel.

   - Refactor the zboot code so that it incorporates all the EFI stub
     logic, rather than calling the decompressed kernel as a EFI app.

   - Add support for initrd= command line option to x86 mixed mode.

   - Allow initrd= to be used with arbitrary EFI accessible file systems
     instead of just the one the kernel itself was loaded from.

   - Move some x86-only handling and manipulation of the EFI memory map
     into arch/x86, as it is not used anywhere else.

   - More flexible handling of any random seeds provided by the boot
     environment (i.e., systemd-boot) so that it becomes available much
     earlier during the boot.

   - Allow improved arch-agnostic EFI support in loaders, by setting a
     uniform baseline of supported features, and adding a generic magic
     number to the DOS/PE header. This should allow loaders such as GRUB
     or systemd-boot to reduce the amount of arch-specific handling
     substantially.

   - (arm64) Run EFI runtime services from a dedicated stack, and use it
     to recover from synchronous exceptions that might occur in the
     firmware code.

   - (arm64) Ensure that we don't allocate memory outside of the 48-bit
     addressable physical range.

   - Make EFI pstore record size configurable

   - Add support for decoding CXL specific CPER records"

* tag 'efi-next-for-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: (43 commits)
  arm64: efi: Recover from synchronous exceptions occurring in firmware
  arm64: efi: Execute runtime services from a dedicated stack
  arm64: efi: Limit allocations to 48-bit addressable physical region
  efi: Put Linux specific magic number in the DOS header
  efi: libstub: Always enable initrd command line loader and bump version
  efi: stub: use random seed from EFI variable
  efi: vars: prohibit reading random seed variables
  efi: random: combine bootloader provided RNG seed with RNG protocol output
  efi/cper, cxl: Decode CXL Error Log
  efi/cper, cxl: Decode CXL Protocol Error Section
  efi: libstub: fix efi_load_initrd_dev_path() kernel-doc comment
  efi: x86: Move EFI runtime map sysfs code to arch/x86
  efi: runtime-maps: Clarify purpose and enable by default for kexec
  efi: pstore: Add module parameter for setting the record size
  efi: xen: Set EFI_PARAVIRT for Xen dom0 boot on all architectures
  efi: memmap: Move manipulation routines into x86 arch tree
  efi: memmap: Move EFI fake memmap support into x86 arch tree
  efi: libstub: Undeprecate the command line initrd loader
  efi: libstub: Add mixed mode support to command line initrd loader
  efi: libstub: Permit mixed mode return types other than efi_status_t
  ...

1 files changed, 35 insertions, 105 deletions

diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
index cf474f0dd261..2955c1ac6a36 100644
--- a/drivers/firmware/efi/libstub/efi-stub.c
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -35,15 +35,6 @@
  * as well to minimize the code churn.
  */
 #define EFI_RT_VIRTUAL_BASE	SZ_512M
-#define EFI_RT_VIRTUAL_SIZE	SZ_512M
-
-#ifdef CONFIG_ARM64
-# define EFI_RT_VIRTUAL_LIMIT	DEFAULT_MAP_WINDOW_64
-#elif defined(CONFIG_RISCV) || defined(CONFIG_LOONGARCH)
-# define EFI_RT_VIRTUAL_LIMIT	TASK_SIZE_MIN
-#else /* Only if TASK_SIZE is a constant */
-# define EFI_RT_VIRTUAL_LIMIT	TASK_SIZE
-#endif
 
 /*
  * Some architectures map the EFI regions into the kernel's linear map using a
@@ -56,6 +47,15 @@
 static u64 virtmap_base = EFI_RT_VIRTUAL_BASE;
 static bool flat_va_mapping = (EFI_RT_VIRTUAL_OFFSET != 0);
 
+struct screen_info * __weak alloc_screen_info(void)
+{
+	return &screen_info;
+}
+
+void __weak free_screen_info(struct screen_info *si)
+{
+}
+
 static struct screen_info *setup_graphics(void)
 {
 	efi_guid_t gop_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
@@ -115,62 +115,21 @@ static u32 get_supported_rt_services(void)
 	return supported;
 }
 
-/*
- * EFI entry point for the arm/arm64 EFI stubs.  This is the entrypoint
- * that is described in the PE/COFF header.  Most of the code is the same
- * for both archictectures, with the arch-specific code provided in the
- * handle_kernel_image() function.
- */
-efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
-				   efi_system_table_t *sys_table_arg)
+efi_status_t efi_handle_cmdline(efi_loaded_image_t *image, char **cmdline_ptr)
 {
-	efi_loaded_image_t *image;
-	efi_status_t status;
-	unsigned long image_addr;
-	unsigned long image_size = 0;
-	/* addr/point and size pairs for memory management*/
-	char *cmdline_ptr = NULL;
 	int cmdline_size = 0;
-	efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
-	unsigned long reserve_addr = 0;
-	unsigned long reserve_size = 0;
-	struct screen_info *si;
-	efi_properties_table_t *prop_tbl;
-
-	efi_system_table = sys_table_arg;
-
-	/* Check if we were booted by the EFI firmware */
-	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
-		status = EFI_INVALID_PARAMETER;
-		goto fail;
-	}
-
-	status = check_platform_features();
-	if (status != EFI_SUCCESS)
-		goto fail;
-
-	/*
-	 * Get a handle to the loaded image protocol.  This is used to get
-	 * information about the running image, such as size and the command
-	 * line.
-	 */
-	status = efi_bs_call(handle_protocol, handle, &loaded_image_proto,
-			     (void *)&image);
-	if (status != EFI_SUCCESS) {
-		efi_err("Failed to get loaded image protocol\n");
-		goto fail;
-	}
+	efi_status_t status;
+	char *cmdline;
 
 	/*
 	 * Get the command line from EFI, using the LOADED_IMAGE
 	 * protocol. We are going to copy the command line into the
 	 * device tree, so this can be allocated anywhere.
 	 */
-	cmdline_ptr = efi_convert_cmdline(image, &cmdline_size);
-	if (!cmdline_ptr) {
+	cmdline = efi_convert_cmdline(image, &cmdline_size);
+	if (!cmdline) {
 		efi_err("getting command line via LOADED_IMAGE_PROTOCOL\n");
-		status = EFI_OUT_OF_RESOURCES;
-		goto fail;
+		return EFI_OUT_OF_RESOURCES;
 	}
 
 	if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) ||
@@ -184,25 +143,34 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 	}
 
 	if (!IS_ENABLED(CONFIG_CMDLINE_FORCE) && cmdline_size > 0) {
-		status = efi_parse_options(cmdline_ptr);
+		status = efi_parse_options(cmdline);
 		if (status != EFI_SUCCESS) {
 			efi_err("Failed to parse options\n");
 			goto fail_free_cmdline;
 		}
 	}
 
-	efi_info("Booting Linux Kernel...\n");
+	*cmdline_ptr = cmdline;
+	return EFI_SUCCESS;
 
-	si = setup_graphics();
+fail_free_cmdline:
+	efi_bs_call(free_pool, cmdline_ptr);
+	return status;
+}
 
-	status = handle_kernel_image(&image_addr, &image_size,
-				     &reserve_addr,
-				     &reserve_size,
-				     image, handle);
-	if (status != EFI_SUCCESS) {
-		efi_err("Failed to relocate kernel\n");
-		goto fail_free_screeninfo;
-	}
+efi_status_t efi_stub_common(efi_handle_t handle,
+			     efi_loaded_image_t *image,
+			     unsigned long image_addr,
+			     char *cmdline_ptr)
+{
+	struct screen_info *si;
+	efi_status_t status;
+
+	status = check_platform_features();
+	if (status != EFI_SUCCESS)
+		return status;
+
+	si = setup_graphics();
 
 	efi_retrieve_tpm2_eventlog();
 
@@ -214,53 +182,15 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 
 	efi_random_get_seed();
 
-	/*
-	 * If the NX PE data feature is enabled in the properties table, we
-	 * should take care not to create a virtual mapping that changes the
-	 * relative placement of runtime services code and data regions, as
-	 * they may belong to the same PE/COFF executable image in memory.
-	 * The easiest way to achieve that is to simply use a 1:1 mapping.
-	 */
-	prop_tbl = get_efi_config_table(EFI_PROPERTIES_TABLE_GUID);
-	flat_va_mapping |= prop_tbl &&
-			   (prop_tbl->memory_protection_attribute &
-			   EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA);
-
 	/* force efi_novamap if SetVirtualAddressMap() is unsupported */
 	efi_novamap |= !(get_supported_rt_services() &
 			 EFI_RT_SUPPORTED_SET_VIRTUAL_ADDRESS_MAP);
 
-	/* hibernation expects the runtime regions to stay in the same place */
-	if (!IS_ENABLED(CONFIG_HIBERNATION) && !efi_nokaslr && !flat_va_mapping) {
-		/*
-		 * Randomize the base of the UEFI runtime services region.
-		 * Preserve the 2 MB alignment of the region by taking a
-		 * shift of 21 bit positions into account when scaling
-		 * the headroom value using a 32-bit random value.
-		 */
-		static const u64 headroom = EFI_RT_VIRTUAL_LIMIT -
-					    EFI_RT_VIRTUAL_BASE -
-					    EFI_RT_VIRTUAL_SIZE;
-		u32 rnd;
-
-		status = efi_get_random_bytes(sizeof(rnd), (u8 *)&rnd);
-		if (status == EFI_SUCCESS) {
-			virtmap_base = EFI_RT_VIRTUAL_BASE +
-				       (((headroom >> 21) * rnd) >> (32 - 21));
-		}
-	}
-
 	install_memreserve_table();
 
 	status = efi_boot_kernel(handle, image, image_addr, cmdline_ptr);
 
-	efi_free(image_size, image_addr);
-	efi_free(reserve_size, reserve_addr);
-fail_free_screeninfo:
 	free_screen_info(si);
-fail_free_cmdline:
-	efi_bs_call(free_pool, cmdline_ptr);
-fail:
 	return status;
 }