1 files changed, 25 insertions, 138 deletions

diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
index 259e4b852d63..2c3869356147 100644
--- a/drivers/firmware/efi/libstub/arm64-stub.c
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -11,73 +11,9 @@
 #include <asm/efi.h>
 #include <asm/memory.h>
 #include <asm/sections.h>
-#include <asm/sysreg.h>
 
 #include "efistub.h"
 
-efi_status_t check_platform_features(void)
-{
-	u64 tg;
-
-	/*
-	 * If we have 48 bits of VA space for TTBR0 mappings, we can map the
-	 * UEFI runtime regions 1:1 and so calling SetVirtualAddressMap() is
-	 * unnecessary.
-	 */
-	if (VA_BITS_MIN >= 48)
-		efi_novamap = true;
-
-	/* UEFI mandates support for 4 KB granularity, no need to check */
-	if (IS_ENABLED(CONFIG_ARM64_4K_PAGES))
-		return EFI_SUCCESS;
-
-	tg = (read_cpuid(ID_AA64MMFR0_EL1) >> ID_AA64MMFR0_EL1_TGRAN_SHIFT) & 0xf;
-	if (tg < ID_AA64MMFR0_EL1_TGRAN_SUPPORTED_MIN || tg > ID_AA64MMFR0_EL1_TGRAN_SUPPORTED_MAX) {
-		if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
-			efi_err("This 64 KB granular kernel is not supported by your CPU\n");
-		else
-			efi_err("This 16 KB granular kernel is not supported by your CPU\n");
-		return EFI_UNSUPPORTED;
-	}
-	return EFI_SUCCESS;
-}
-
-/*
- * Distro versions of GRUB may ignore the BSS allocation entirely (i.e., fail
- * to provide space, and fail to zero it). Check for this condition by double
- * checking that the first and the last byte of the image are covered by the
- * same EFI memory map entry.
- */
-static bool check_image_region(u64 base, u64 size)
-{
-	struct efi_boot_memmap *map;
-	efi_status_t status;
-	bool ret = false;
-	int map_offset;
-
-	status = efi_get_memory_map(&map, false);
-	if (status != EFI_SUCCESS)
-		return false;
-
-	for (map_offset = 0; map_offset < map->map_size; map_offset += map->desc_size) {
-		efi_memory_desc_t *md = (void *)map->map + map_offset;
-		u64 end = md->phys_addr + md->num_pages * EFI_PAGE_SIZE;
-
-		/*
-		 * Find the region that covers base, and return whether
-		 * it covers base+size bytes.
-		 */
-		if (base >= md->phys_addr && base < end) {
-			ret = (base + size) <= end;
-			break;
-		}
-	}
-
-	efi_bs_call(free_pool, map);
-
-	return ret;
-}
-
 efi_status_t handle_kernel_image(unsigned long *image_addr,
 				 unsigned long *image_size,
 				 unsigned long *reserve_addr,
@@ -85,92 +21,43 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 				 efi_loaded_image_t *image,
 				 efi_handle_t image_handle)
 {
-	efi_status_t status;
-	unsigned long kernel_size, kernel_memsize = 0;
-	u32 phys_seed = 0;
-
-	/*
-	 * Although relocatable kernels can fix up the misalignment with
-	 * respect to MIN_KIMG_ALIGN, the resulting virtual text addresses are
-	 * subtly out of sync with those recorded in the vmlinux when kaslr is
-	 * disabled but the image required relocation anyway. Therefore retain
-	 * 2M alignment if KASLR was explicitly disabled, even if it was not
-	 * going to be activated to begin with.
-	 */
-	u64 min_kimg_align = efi_nokaslr ? MIN_KIMG_ALIGN : EFI_KIMG_ALIGN;
-
-	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
-		efi_guid_t li_fixed_proto = LINUX_EFI_LOADED_IMAGE_FIXED_GUID;
-		void *p;
+	unsigned long kernel_size, kernel_codesize, kernel_memsize;
 
-		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) {
-				efi_info("EFI_RNG_PROTOCOL unavailable\n");
-				efi_nokaslr = true;
-			} else if (status != EFI_SUCCESS) {
-				efi_err("efi_get_random_bytes() failed (0x%lx)\n",
-					status);
-				efi_nokaslr = true;
-			}
-		}
-	}
-
-	if (image->image_base != _text)
+	if (image->image_base != _text) {
 		efi_err("FIRMWARE BUG: efi_loaded_image_t::image_base has bogus value\n");
+		image->image_base = _text;
+	}
 
 	if (!IS_ALIGNED((u64)_text, SEGMENT_ALIGN))
 		efi_err("FIRMWARE BUG: kernel image not aligned on %dk boundary\n",
 			SEGMENT_ALIGN >> 10);
 
 	kernel_size = _edata - _text;
+	kernel_codesize = __inittext_end - _text;
 	kernel_memsize = kernel_size + (_end - _edata);
 	*reserve_size = kernel_memsize;
+	*image_addr = (unsigned long)_text;
 
-	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && phys_seed != 0) {
-		/*
-		 * If KASLR is enabled, and we have some randomness available,
-		 * locate the kernel at a randomized offset in physical memory.
-		 */
-		status = efi_random_alloc(*reserve_size, min_kimg_align,
-					  reserve_addr, phys_seed);
-		if (status != EFI_SUCCESS)
-			efi_warn("efi_random_alloc() failed: 0x%lx\n", status);
-	} else {
-		status = EFI_OUT_OF_RESOURCES;
-	}
-
-	if (status != EFI_SUCCESS) {
-		if (!check_image_region((u64)_text, kernel_memsize)) {
-			efi_err("FIRMWARE BUG: Image BSS overlaps adjacent EFI memory region\n");
-		} else if (IS_ALIGNED((u64)_text, min_kimg_align)) {
-			/*
-			 * Just execute from wherever we were loaded by the
-			 * UEFI PE/COFF loader if the alignment is suitable.
-			 */
-			*image_addr = (u64)_text;
-			*reserve_size = 0;
-			return EFI_SUCCESS;
-		}
+	return efi_kaslr_relocate_kernel(image_addr, reserve_addr, reserve_size,
+					 kernel_size, kernel_codesize, kernel_memsize,
+					 efi_kaslr_get_phys_seed(image_handle));
+}
 
-		status = efi_allocate_pages_aligned(*reserve_size, reserve_addr,
-						    ULONG_MAX, min_kimg_align);
+asmlinkage void primary_entry(void);
 
-		if (status != EFI_SUCCESS) {
-			efi_err("Failed to relocate kernel\n");
-			*reserve_size = 0;
-			return status;
-		}
-	}
-
-	*image_addr = *reserve_addr;
-	memcpy((void *)*image_addr, _text, kernel_size);
+unsigned long primary_entry_offset(void)
+{
+	/*
+	 * When built as part of the kernel, the EFI stub cannot branch to the
+	 * kernel proper via the image header, as the PE/COFF header is
+	 * strictly not part of the in-memory presentation of the image, only
+	 * of the file representation. So instead, we need to jump to the
+	 * actual entrypoint in the .text region of the image.
+	 */
+	return (char *)primary_entry - _text;
+}
 
-	return EFI_SUCCESS;
+void efi_icache_sync(unsigned long start, unsigned long end)
+{
+	caches_clean_inval_pou(start, end);
 }